Biology Review (Pearson questions)
Herpes simplex viruses, such as those that cause cold sores, can evade the immune system and persist in the body by __________.
infecting cells and then entering a largely inactive state
From the capillaries of the abdominal organs and hind limbs, blood flows to the _____.
inferior vena cava
Anaphylactic shock is a life-threatening condition in which __________.
inflammatory chemicals released from mast cells lead to an inability to breathe and a lack of blood flow
Choose the list that presents the four stages of food processing in the order in which they naturally occur. See Concept 41.2 (Page)
ingestion → digestion → absorption → elimination
All proteins are synthesized by ribosomes in the cell. Some ribosomes float freely in the cytosol, while others are bound to the surface of the endoplasmic reticulum. Most proteins made by free ribosomes function in the cytosol. Proteins made by bound ribosomes either function within the endomembrane system or pass through it and are secreted from the cell. Which of the following proteins are synthesized by bound ribosomes? Select all that apply ribosomal protein actin insulin ER protein DNA polymerase lysosomal enzyme
insulin ER protein lysosomal enzyme
When blood glucose levels rise in an animal, _______ is secreted to trigger the uptake of glucose from the blood into body cells; but when glucose levels decline, _______ is secreted to promote the release of glucose into the blood.
insulin; glucagon
Humid weather makes you feel warmer because humid air, which is saturated with water molecules, __________.
interferes with heat loss by evaporation
An antigen _____. See Concept 43.2 (Page)
is a foreign molecule that evokes a specific response by a lymphocyte
Type 1 diabetes mellitus __________.
is an autoimmune disease in which the immune system attacks beta cells in the pancreas
Characteristic of the bdelloid rotifer is that it __________.
is an example of an animal that has not reproduced sexually in 40 million years
Passive immunity differs from active immunity in that passive immunity ___________.
is conferred by antibodies produced by another individual
Any signaling molecule referred to as a neurohormone __________.
is produced by a neuron
Molecules that have the same chemical formula (same numbers of each atom) but different three-dimensional shapes are called _____
isomers
The avian flu virus H5N1 is considered a greater long-term threat than the swine flu virus H1N1 because __________.
it has a significantly higher mortality rate
The major contribution of sex to evolution is that __________.
it provides a method to increase genetic variation
The loops of Henle in the kidneys of a desert kangaroo rat are much longer than those in a white laboratory rat because the __________.
kangaroo rat is adapted to living in an environment where water is scarce
Heart valves function to __________.
keep blood moving in the correct direction
Can you match these prefixes, suffixes, and word roots with their definitions? moving:
kin- (or kinet-)
Can you match these prefixes, suffixes, and word roots with their definitions? milk:
lac- (or lact-)
Voice sounds are produced by the _____.
larynx
Suppose that the botanist carried out the test cross described in Parts A and B and determined that the original green-pod plant was heterozygous (Gg). Which of Mendel's findings does her test cross illustrate?
law of segregation
As the two parental (template) DNA strands separate at a replication fork, each of the strands is separately copied by a DNA polymerase III (orange), producing two new daughter strands (light blue), each complementary to its respective parental strand. Because the two parental strands are antiparallel, the two new strands (the leading and lagging strands) cannot be synthesized in the same way. Drag each phrase to the appropriate bin depending on whether it describes the synthesis of the leading strand, the synthesis of the lagging strand, or the synthesis of both strands.
leading strand: -made continuously -daughter strand elongates toward replication fork -only one primer needed lagging strand: -made in segments -daughter strand elongates away from replication fork -multiple primers needed both strands: synthesized 5' to 3'
From the pulmonary veins, blood flows to the _____
left atrium
Bile is produced by the _____ and stored by the _____ until it is secreted into the small intestine.
liver ... gall bladder
The major tropic action of growth hormone is to signal the ________ to release _________.
liver; insulin-like growth factors (IGFs)
A goiter may form because __________.
low blood levels of T3 and T4 inhibit the negative feedback loop, and an overload of TSH causes enlargement of the gland
Which hormone stimulates hormone production by the ovaries and testes?
luteinizing hormone (LH)
A phage that inserts itself into the host DNA is called __________.
lysogenic
Cycle A is the _____ cycle and cycle B is the _____ cycle.
lytic ... lysogenic
The phage reproductive cycle that kills the bacterial host cell is a __________ cycle, and a phage that always reproduces this way is a __________ phage.
lytic; virulent
Which of these cells is a phagocytic leukocyte that can engulf a foreign bacterium?
macrophage
Compared to peas, fruit flies were thought to have no variations, until the discovery of a __________ fly by __________.
male white-eyed; Morgan
An insufficient supply of chemical energy in the diet or a shortage of one or more essential nutrients results in __________.
malnutrition
glucose + glucose —> _____ by _____.
maltose + water ... dehydration synthesis
Individuals with an extra X chromosome __________.
may have subnormal intelligence or be at risk for learning disabilities
The kidney's ability to concentrate urine depends on the maintenance of an osmolarity gradient between the interstitial fluid of two structures: the cortex and the __________________
medulla
During which part of meiosis (meiosis I or meiosis II) do the two alleles of a gene separate? During which phase does the separation occur? State your answer as meiosis I or meiosis II followed by a comma and the name of the phase (for example, if your answer is meiosis II and metaphase, enter meiosis II, metaphase).
meiosis I, anaphase
Which of these cells is responsible for the rapidity of the secondary immune response?
memory cells
Which of the compounds shown in the data table in Figure 1 could be made in the H2S experiment but could not be made in the earlier experiment (Figure 3)?
methionine
Which of these is a source of lactose?
milk
The sickle-cell β-globin mutation is an example of a __________.
missense mutation
A fat molecule with only ONE fatty acid is called a __________________________.
monoglyceride
The effect of the environment on a phenotype is referred to as __________.
multifactorial
A primary reason for needing a new vaccine for influenza each year is that _____. See Concept 43.4 (Page)
mutation in the influenza virus is frequent
The primary functions of the _____ are to warm, filter, and humidify air.
nasal cavity
The response of the heating system reduces the stimulus. This is an example of ______________ feedback.
negative
What functional feature(s) does the phosphate group contribute to the structure of a phospholipid? negative charge to interact with water place to attach another small charged molecule place where bonds can form between adjoining phospholipids nonpolar group that avoids water place to attach fatty acids
negative charge to interact with water place to attach another small charged molecule
When a person's body temperature increases, sweating helps bring the temperature down. This is an example of __________.
negative feedback
Which of these is the functional unit of a kidney?
nephron
The __________ system and the __________ system work together to coordinate and control the bodies of most animals.
nervous; endocrine
The type of point mutation that results in a premature stop codon is called a _________ mutation.
nonsense
In meiosis, __________ of __________ cross over and form __________.
nonsister chromatids; homologous pairs; chiasmata
How do nonsteroid hormones differ from steroid hormones?
nonsteroid hormones act via signal transduction pathways; steroid hormones do not act via signal transduction pathways
This pair of molecules are _____.
not isomers
Proteins that are involved in packaging the eukaryotic chromosome into "beads" called __________ are __________.
nucleosomes; histones
This is an image of a(n) _________________
nucleotide
By bombarding the fungus Neurospora crassa with X-rays, Beadle and Tatum were able to study __________ and characterize enzymes in a __________.
nutritional mutants; biochemical pathway
Which of these is a phospholipid?
olive oil
A linkage map __________.
orders genes on a chromosome based on recombination frequencies
An albatross spending its life hovering over the ocean provides an extreme example of __________, the process by which animals control solute concentrations and balance water gain and loss.
osmoregulation
Terrestrial animals are _____. See Concept 44.1 (Page)
osmoregulators that must obtain water from the environment
Water responds to the osmolarity gradient by moving from an area of lower solute concentration to an area of higher solute concentration--a process called _____________________
osmosis
To control breathing, the medulla of the human brain monitors the ________ of the blood and then sends out signals so that appropriate physiological adjustments can be made.
pH
Secretin stimulates the _____ to secrete _____.
pancreas ... bicarbonate
Cholecystokinin (CCK) stimulates the _____ to secrete _____.
pancreas ... pancreatic enzymes
A cell releases a cytokine, which binds to, and acts on, a neighboring cell. This represents an example of __________.
paracrine signaling
The structures called snRNPs are __________.
part of a spliceosome
Which of the following is not a class I virus?
parvovirus
Osmosis does not require energy. For this reason, osmosis is a form of ___________________________
passive transport
Griffith showed that dead __________ cells __________ living __________ cells into living __________ cells.
pathogenic; transform; nonpathogenic; pathogenic
The role of cytotoxic T cells is the secretion of _____, which plays a role in the _____ immune response.
perforin ... cell-mediated
In vertebrates, food is moved along the length of the digestive system by __________.
peristalsis
A hydroxyl is present at the 3' end of the growing DNA strand. What is at the 5' end?
phosphate group
The letter A indicates a _________________
phosphate group
The 5ꞌ end of a DNA strand always has a free __________ group while the 3ꞌ end always has a free __________ group.
phosphate; hydroxyl
All of the following types of viruses have envelopes except __________.
picornovirus
B cells that have been stimulated by interleukin-2 develop into _____.
plasma cells
Which of these cells produce and secrete antibodies?
plasma cells
In blood, the matrix component is ________, and the cellular component contains _________.
plasma; red and white blood cells
Candidates for the original source of viral genomes include __________.
plasmids and transposons
In humans, height and skin color have continuous variation in the population because of __________.
polygenic inheritance
Asexual reproduction _____. See Concept 13.1 (Page)
produces offspring genetically identical to the parent
Which hormone stimulates milk production?
prolactin
One strand of a DNA molecule has the following sequence: 3-AGTACAAACTATCCACCGTC-5. In order for transcription to occur in that strand, there would have to be a specific recognition sequence, called a(n) __________, to the left of the DNA sequence indicated.
promoter
Viral DNA incorporated into a bacterial chromosome is known as a(n) __________.
prophage
Ibuprofen is known for its pain-relieving and anti-inflammatory properties because it inhibits the synthesis of __________.
prostaglandins
Most of our nitrogen-containing waste products are a result of __________.
protein metabolism
In the famous Hershey and Chase "blender experiment," radioactive sulfur was used to label __________, and radioactive phosphorus was used to label __________, demonstrating that the genetic material of a bacteriophage is __________.
protein; DNA; DNA
Myosin and actin are __________.
proteins that play a major role in muscle contraction
Double-stranded viral DNA is incorporated into a host cell as a _____.
provirus
Blood returns to the heart via the _____.
pulmonary veins Pulmonary veins carry oxygenated blood from the lungs to the left atrium.
How do prions differ from viruses? Select all that apply.
(All three options) -Unlike a virus, a prion is a single molecule. -Unlike viruses, prions are infectious proteins. -Unlike viruses, prions do not include any nucleic acids.
The images below show two countercurrent heat exchangers in marine animals: in the flipper of a sea turtle (left) and in the abdomen of a dolphin (right).
(Three answers) -In a sea turtle's flippers, heat is transferred from (1) to (3) -In a dolphin, blood cools as it flows from the aorta to the testes. -At a dolphin's testes, heat is transferred from (1) to (2).
Which of the following helps most to explain why water has a high specific heat?
(a) A water molecule can make 4 hydrogen bonds.
In the animation, you saw that both high blood glucose levels and low blood glucose levels are stimuli that trigger specific responses by the body. These responses cause blood glucose levels to return to their normal range. In this activity, you will explore how this happens. Drag the labels to their appropriate locations on the diagram.
- A. Beta cells of pancreas release insulin- B. Body cells take up more glucose- C. Liver takes up glucose and builds glycogen- D. Blood glucose levels fall- E. Alpha cells of pancreas release glucagon- F. Liver breaks down glycogen and releases glucose- G. Blood glucose levels rise
Which statements about viruses are true? Select the four statements that are true.
-Enveloped viruses bud from the host cell. -A retrovirus contains RNA -HIV contains reverse transcriptase. -The capsid enters the host cell if the virus is enveloped.
After transcription begins, several steps must be completed before the fully processed mRNA is ready to be used as a template for protein synthesis on the ribosomes. Which three statements correctly describe the processing that takes place before a mature mRNA exits the nucleus?
-Noncoding sequences called introns are spliced out by molecular complexes called spliceosomes. -A poly-A tail (50-250 adenine nucleotides) is added to the 3' end of the pre-mRNA. -A cap consisting of a modified guanine nucleotide is added to the 5' end of the pre-mRNA.
In the disorder diabetes mellitus, the body is unable to maintain homeostasis of blood glucose. There are two major types of diabetes, type 1 and type 2. The graphs below show blood levels of glucose and insulin in three patients after each has consumed a sugary soft drink. Use the graphs to identify which patient is healthy, which has type 1 diabetes, and which has type 2 diabetes. Drag the labels to their appropriate locations above the graphs.
-Patient A: Type 1 Diabetes - Patient B: Healthy - Patient C: Type 2 Diabetes
Can you match these prefixes, suffixes, and word roots with their definitions? enzyme:
-ase
The fact that there are about a million different antigen receptors possible in human B cells is based on _____. See Concept 43.2 (Page)
recombination of the segments of the receptor DNA that make up the functional receptor genes of differentiated B cells
In a cross between wild-type (red-eyed) female flies and mutant white-eyed male flies, the F1 generation should always produce females with __________ eyes and males with __________ eyes.
red, red
Birds, insects, and many reptiles excrete nitrogenous waste in the form of uric acid, which _____. See Concept 44.2 (Page)
reduces water loss compared to other nitrogenous wastes, but requires more metabolic energy to produce
Muscle tissues make lactate from pyruvate to do which of the following?
regenerate NAD+
The lower esophageal sphincter surrounds the upper opening into the stomach. If this sphincter failed to properly constrict, there might be a problem with _____. See Concept 41.3 (Page)
regurgitation of acidic stomach contents into the esophagus, commonly called "heartburn"
An exergonic (spontaneous) reaction is a chemical reaction that __________.
releases energy when proceeding in the forward direction
An exergonic reaction __________ free energy, and an endergonic reaction __________ free energy
releases; absorbs
The _____ are the major blood vessels transporting blood to the kidneys.
renal arteries
Urine formed by a kidney collects in the _____ before being drained from the kidney by the _____ and transported to the _____.
renal pelvis ... ureter ...urinary bladder
Telomeres are __________.
repeating noncoding sequences at the ends of linear eukaryotic chromosomes
The experiments of Meselson and Stahl showed that DNA __________.
replicates in a semiconservative fashion
DNA replication begins at a site called the origin of replication, forming a bubble, which is followed by a __________, where parental strands are unwound by __________.
replication fork; helicases
Can you match these prefixes, suffixes, and word roots with their definitions? change, turn, move:
-trop-
The overall error rate in the completed DNA molecule is approximately __________.
1 error per 10,000,000,000 nucleotides
What is the maximum number of moles of glycine (C2H5NO2) that could be made in the flask if no other molecules were made?
1 mole of glycine
In a nucleotide, the nitrogenous base is attached to the sugar's _____ carbon and the phosphate group is attached to the sugar's _____ carbon.
1' ... 5'
In glycolysis, as in all the stages of cellular respiration, the transfer of electrons from electron donors to electron acceptors plays a critical role in the overall conversion of the energy in foods to energy in ATP. These reactions involving electron transfers are known as oxidation-reduction, or redox, reactions
1) Oxidized 2) Reduced 3) Glucose 4) Pyruvate 5) NAD⁺ 6) NADH
A pH of 6 is how many times more acidic than a pH of 9?
1,000
Under normal conditions, a pair of human kidneys processes what volume of blood each day?
1,600 L
Plant and animal cells also require cytoskeletal proteins for cytokinesis, although the roles these proteins play differ among bacteria, plants, and animals. For each space in the table, drag the appropriate label to indicate if the statement is true or false for each group of organisms. 1. Cells divide by constriction of a ring of protein 2. The presence of a cell wall prevents the cell from dividing by contrictrion 3. Tubulin or tubulin-like molecules function in binary fission (in bacteria) or cytokinesis (in animals and plants)
1. Bacteria - true Animals- true Plants- false 2. Bacteria - false Animals- false Plants- true 3. Bacteria - true Animals- false Plants- true
Individuals III-3 and III-4 are expecting their first child when they become aware that they both have a family history of this recessive condition. As their genetic counselor, you can calculate the probability that they are carriers and that their child will be affected with the condition. Complete each statement by dragging the correct label to the appropriate location. Labels can be used once, more than once, or not at all.
1. 2/3 2. 1/2 3. 1/12
Suppose a diploid cell with three pairs of homologous chromosomes (2n = 6) enters meiosis. How many chromosomes will the resulting gametes have in each of the following cases? Drag one label into each space at the right of the table. Labels can be used once, more than once, or not at all.
1. 3 only 2. 2 or 4 3. 0 or 6 4. 2, 3, or 4 5. 0, 3, or 6
Inhalation and exhalation move air into and out of the lungs. What happens when you inhale and exhale? Drag the labels to the correct locations on the flowchart to identify the steps of inhalation and exhalation.
1. Diaphragm anf rib muscles contract 2. Lung volume increases 3. Air moves into nose and down trachea, bronchi, and bronchioles 4. Air enters alveoli 5. O2 diffuses into bloof; Co2 diffuses into alveoli 6. Diaphragm and rib muscles relax 7. Lung volume dcreases 8. Air moves out of alveoli 9. Air moves up bronchioles, brochi, and trachea 10. Air leaves nose or mouth
The diagram below shows two normal chromosomes in a cell. Letters represent major segments of the chromosomes. The following table illustrates some structural mutations that involve one or both of these chromosomes. Identify the type of mutation that has led to each result shown. Drag one label into the space to the right of each chromosome or pair of chromosomes. You can use a label once, more than once, or not at all.
1. deletion 2. duplication 3. translocation 4. inversion 5. duplication 6. translocation 7. inversion
The mitotic spindle consists of two types of microtubules: kinetochore microtubules and nonkinetochore microtubules. In animal cells, these two types of microtubules function differently in the stages of mitosis. Complete the sentences by dragging the terms to the appropriate locations. Terms may be used once, more than once, or not at all. 1. During prophase, the microtubules of the mitotic spindle_______________ 2. During anaphase, the nonkinetochore microtubules ___________ and move past each other, and the kinetochore microtubules _________________. 3. During telophase, the nonkinetochore microtubules ____________________.
1. lengthen 2. lengthen. shorten 3. Disassemble
Consider an animal cell in which motor proteins in the kinetochores normally pull the chromosomes along the kinetochore microtubules during mitosis. Suppose, however, that during metaphase, this cell was treated with an inhibitor that blocks the function of the motor proteins in the kinetochore, but allows the kinetochore to remain attached to the spindle. The inhibitor has no effect on any other mitotic process, including the function of the nonkinetochore microtubules. Consider three questions concerning the animal cell that has been treated with the inhibitor. Drag the terms to answer the questions. Terms may be used once, more than once, or not at all. 1. Will this cell elongate during mitosis? 2. Will the sister chromatids separate from each other? 3. Will the chromosomes move to the poles of the cell?
1. yes 2. yes 3. no
If a heterozygous plant is allowed to self-pollinate, what proportion of the offspring will also be heterozygous?
1/2
One character in peas that Mendel studied was yellow versus green seeds. A cross between a homozygous yellow line (YY) and a homozygous green line (yy) will result in F1 plants that are heterozygous (Yy) for this trait and produce yellow seeds. When an F1 plant undergoes meiosis, what gamete types will it produce, and in what proportions?
1/2 y, 1/2 y
2. What is the probablity that an F2 seed chosen at random from among the yellow seeds will breed true when selfed?
1/3
Down syndrome is caused by trisomy 21, the presence of three copies of chromosome 21. The extra copy usually results from nondisjunction during meiosis. In some cases, however, the extra copy results from a translocation of most of chromosome 21 onto chromosome 14. A person who has had such a translocation in his or her gamete-producing cells is a carrier of familial Down syndrome. The carrier is normal because he or she still has two copies of all the essential genes on chromosome 21, despite the translocation. However, the same may not be true for the carrier's offspring.The diagram shows the six possible gametes that a carrier of familial Down syndrome could produce. Suppose that a carrier of familial Down syndrome mated with a person with a normal karyotype. Which gamete from the carrier parent could fuse with a gamete from the normal parent to produce a trisomy-21 zygote? Drag one of the gamete cells to the target of Group 1 in the diagram. Drag one of the zygote cells to the target of Group 2 in the diagram.
14 (green) 21 (yellow) 21 (yellow) (Blue outline) x 14 (green) 21 (yellow) = 14 (green) 14 (green) 21 (yellow) 21 (yellow) 21 (yellow) (red outline)
Ignoring crossover, how many kinds of gametes can be produced by an organism with a diploid number of 8?
16
To view the animation, click here. Then click Start on the image to start the animation. What enzyme is responsible for the process seen here?
reverse transcriptase
Based on the graph, what is the optimal pH for pepsin activity?
2
How many chambers are typically found in the heart of organisms with single circulation circulatory systems?
2
How many fatty acids are in a phospholipid?
2
In contrast to the leading strand, the lagging strand is synthesized as a series of segments called Okazaki fragments. The diagram below illustrates a lagging strand with the replication fork off-screen to the right. Fragment A is the most recently synthesized Okazaki fragment. Fragment B will be synthesized next in the space between primers A and B.
2) pol III moves 5' to 3', adding DNA nucleotides to primer B 3) pol I binds to 5' end of primer A 4) pol I replaces primer A with DNA 5) DNA ligase links fragments A and B
A cell contains 40 chromatids at the beginning of mitosis. How many chromosomes will it contain at the completion of cytokinesis?
20
4. What is the probability that three F2 seeds chosen at random will include one green seed and two yellow seeds?
27/64
Scan along the standard sequences (O. kisutch, O. keta, and S. salar), base by base, identifying any bases that do not match the sequence from your fish sample. How many nucleotide bases differ between your sample (labeled as O. kisutch) and the standard sequence for O. kisutch? Sample labeled as O. kisutch5'- CGGCACCGCCCTAAGTCTCT-3'O. kisutch (coho salmon) standard5'-AGGCACCGCCCTAAGTCTAC-3'
3
DNA polymerase adds nucleotides to the __________ of the leading strands, and to the __________ of the lagging strands (Okazaki fragments).
3' end; 3' end
What is the proper order of the following events in the expression of a eukaryotic gene? 1. translation 2. RNA processing 3. transcription 4. modification of protein
3, 2, 1, 4
1. What is the probability that an F2 seed chosen at random will be yellow?
3/4
In DNA replication, the next nucleotide is incorporated into the growing polymer at the __________ of the molecule by an enzyme called __________.
3ꞌ (hydroxyl) end; DNA polymerase
The egg (ovum) of a rabbit contains 22 chromosomes. How many chromosomes are in the somatic (body) cells of a rabbit?
44
How many different kinds of nucleotides does DNA contain?
4: A, C, T, G
Life as we know it depends on the genetic code: a set of codons, each made up of three bases in a DNA sequence and corresponding mRNA sequence, that specifies which of the 20 amino acids will be added to the protein during translation. Imagine that a prokaryote-like organism has been discovered in the polar ice on Mars. Interestingly, these Martian organisms use the same DNA → RNA → protein system as life on Earth, except that there are only 2 bases (A and T) in the Martian DNA, and there are only 17 amino acids found in Martian proteins. Based on this information, what is the minimum size of a codon for these hypothetical Martian life-forms?
5 bases
Nucleic acids are assembled in the _____ direction.
5' to 3'
Given a template strand of 3'-ATGCTTGGACA-5' and a partially-made complementary strand containing only 5'-TAC-3', what would be the sequence of the new strand of DNA (including the 5'-TAC-3') if the only additional nucleotides available to DNA polymerase were those containing the bases G, A, and C?
5'-TACGAACC-3'
What enzyme allows a retrovirus to make DNA from an RNA template?
reverse transcriptase
In werewolves (hypothetically), pointy ears (P) are dominant over round ears (p). The gene is on the X chromosome. (Sex determination in werewolves is the same as for "other" humans.) A certain female werewolf has pointy ears even though her father had round ears. What percentage of her sons will have round ears if she mates with a werewolf with round ears?
50%
If there is 1.0 mole of glycine present in the sample, how many more molecules of alanine are present?
6.02 x 10^22
3. What is the probability that three F2 seeds chosen at random will include at least one yellow seed?
63/64
Based on the graph, what is the optimal pH for trypsin activity?
8
Approximately how much more free energy is supplied to the electron transport chain by NADH than by FADH2?
8 kcal/mol
What percentage of the bases in the standard sequence for O. kisutch are identical to your sample? This value is called the "percent identity."
85%
How many chromatids does a human somatic cell contain after interphase and just prior to mitosis?
92
Which letter indicates systolic pressure?
A
Which of the functional groups behaves as a base?
A
Which of these binds to receptor molecules on the host cell membrane?
A
Which one of these is an amino group?
A
In analyzing the number of different bases in a DNA sample, which result would be consistent with the base-pairing rules?
A + G = C + T
During acetyl CoA formation and the citric acid cycle, all of the carbon atoms that enter cellular respiration in the glucose molecule are released in the form of CO2. Use this diagram to track the carbon-containing compounds that play a role in these two stages. Drag the labels from the left (which represent numbers of carbon atoms) onto the diagram to identify the number of carbon atoms in each intermediate in acetyl CoA formation and the citric acid cycle. Labels may be used more than once.
A - 2C B - 6C C - 6C D - 5C E- 4C F -4C G - 4C H - 4C I - 4C
In the sequential reactions of acetyl CoA formation and the citric acid cycle, pyruvate (the output from glycolysis) is completely oxidized, and the electrons produced from this oxidation are passed on to two types of electron acceptors. Drag the labels on the left to show the net redox reaction in acetyl CoA formation and the citric acid cycle. Note that two types of electron carriers are involved.
A - CO2 B - NADH C- FAD D - FADH2
The four stages of cellular respiration do not function independently. Instead, they are coupled together because one or more outputs from one stage functions as an input to another stage. The coupling works in both directions, as indicated by the arrows in the diagram below. In this activity, you will identify the compounds that couple the stages of cellular respiration. Drag the labels onto the diagram to identify the compounds that couple each stage. Labels may be used once, more than once, or not at all.
A - Pyruvate B - NADH C - NAD+ D - NADH E - NAD+
What is the physiological cause of a heart attack?
A blood clot lodging in a blood vessel supplying the heart
Which of the following is an example of a portal vein?
A blood vessel carrying blood from the stomach to the liver
The region of a chromosome holding the two double strands of replicated DNA together is called __________.
A centromere
Which of the following might make the most effective medication to treat gastric ulcers?
A chemical that kills bacteria in the stomach
In insects, which of the following is analogous to mammalian epithelial tissue, in that it serves as a first line of defense against infection?
A chitinous exoskeleton
What happens when the CO2 level from cellular respiration increases in the blood?
A decrease in the pH of the cerebrospinal fluid triggers the brain's breathing control centers, which stimulate diaphragm and rib muscle contractions.
Which molecule is less soluble in water--a fat or a phospholipid? Why? A phospholipid is less soluble in water because it is smaller than a fat molecule. A phospholipid is less soluble in water because even though it has one end that is hydrophilic, the end that is hydrophobic is larger. A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has .A fat molecule is less soluble in water because it has more carbons and hydrogens than a phospholipid
A fat molecule is less soluble in water because it has three non-polar fatty acids and no polar or charged head like a phospholipid has
Which of the following statements correctly describes the difference(s) between a gastrovascular cavity and an alimentary canal?
A gastrovascular cavity has only one opening, and an alimentary canal has two openings.
Which of the following characteristics is likely to be found in larger versus smaller animals?
A highly branched respiratory system
The diagram below shows an mRNA molecule that encodes a protein with 202 amino acids. The start and stop codons are highlighted, and a portion of the nucleotide sequence in the early part of the molecule is shown in detail. At position 35, a single base-pair substitution in the DNA has changed what would have been a uracil (U) in the mRNA to an adenine (A). Based on the genetic code chart above, which of the following would be the result of this single base-pair substitution?
A nonsense mutation resulting in early termination of translation
__________ occurs when a single gene affects the phenotype of many characters in an individual.
A pleiotropic effect
Which of the following statements about equilibrium of chemical reactions is correct?
A reaction that is at equilibrium is not capable of doing any work.
HIV uses which of the following processes to synthesize a DNA strand using its RNA genome as a template? See Concept 19.2 (Page)
reverse transcription
Why did Morgan choose Drosophila for his genetics experiments?
A single mating can produce many offspring and Drosophila chromosomes can be easily distinguishable under a light microscope.
Why is a frameshift missense mutation more likely to have a severe effect on phenotype than a nucleotide-pair substitution missense mutation in the same protein?
A substitution missense affects only one codon, but a frameshift missense affects all codons downstream of the frameshift.
Human blood groups are governed by three alleles, IA, IB, and i. IA and IB are codominant and i is recessive to both. A man who has type B blood and a woman who has type A blood could have children of which of the following phenotypes?
A, B, AB, or O
In eukaryotic cells, the processes of protein synthesis occur in different cellular locations. Drag the labels to the appropriate targets to identify where in the cell each process associated with protein synthesis takes place.
A. Formation of ribosomal units B. Attachment of an amino acid to tRNA C. Translation of cytoplasmic proteins D. Transcription and RNA processing E. Translation of secreted proteins
The phylogenetic tree shows the hypothesized evolutionary relationship between the variant strains of H1N1 virus. Each branch tip is one variant of the H1N1 virus with a unique HA gene sequence. The more closely connected two variants are, the more alike they are in terms of HA gene sequence. Each fork in a branch, called a node, shows where two lineages separate due to different accumulated mutations. The number of nodes separating two variants is an indication of how many DNA sequence differences there are between the variants, thus how distantly related they are. Referring to the phylogenetic tree in Figure 1, which variant is more closely related to A/Taiwan1018/2011 in group 9 (brown): A/Taiwan/552/2011 or A/Taiwan/8542/2009? (For help reading the phylogenetic tree, see the hint.)
A/Taiwan/552/2011; variants 1018/2011 and 552/2011 share a more recent common ancestor than is shared with variant 8542/2009.
Prolactin (PRL) is a pituitary hormone that regulates milk production in lactating mammals. PRL production is controlled by hormones produced in the hypothalamus. In response to either the presence or absence of a specific stimulus, a signal is sent to the brain that triggers the hypothalamus to secrete either a releasing hormone or an inhibitory hormone. The flowchart below shows the pathways for PRL production and regulation. Drag the labels onto the flowchart to identify the pathways for prolactin (PRL) production and regulation. Not all labels will be used.
A: suckling by young B: Hypothalamus C: Dopamine D: TRH E: Anterior pituitary F: Mammary glands G: Milk production
In cells, what is usually the immediate source of energy for an endergonic reaction?
ATP
What does this chart represent?
ATP
As ATP begins to build up in a cell, metabolism slows down. How does this happen?
ATP acts as an allosteric inhibitor to many of the enzymes involved in metabolism, thus slowing their function.
Cells use ATP constantly, but ATP is considered a renewable resource. What process makes this possible?
ATP can be regenerated by the addition of a phosphate group to ADP.
The rate of cellular respiration is regulated by its major product, ATP, via feedback inhibition. As the diagram shows, high levels of ATP inhibit phosphofructokinase (PFK), an early enzyme in glycolysis. As a result, the rate of cellular respiration, and thus ATP production, decreases. Feedback inhibition enables cells to adjust their rate of cellular respiration to match their demand for ATP. Which statement correctly describes how this increased demand would lead to an increased rate of ATP production?
ATP levels would fall at first, decreasing the inhibition of PFK and increasing the rate of ATP production.
An epithelial cell with a relatively large amount of cytoplasm probably has what function?
Absorption and secretion
Compare the relative abundance of Actinobacteria in the microbiome of a healthy adult's intestinal tract to that of a healthy adult's stomach. Which statement best represents the relative abundance of Actinobacteria in each?
Actinobacteria are abundant in the stomach, but rare in the intestinal tract of healthy adults.
The graph here shows a comparison of the stomach microbiomes of healthy adults versus adults infected with Helicobacter pylori, a type of bacteria that has been linked to the formation of stomach ulcers. Which statement best represents the bacterial community composition of a healthy adult's stomach?
Actinobacteria are the most abundant bacteria in the stomach of healthy adults, followed by Firmicutes, and roughly equal amounts of Bacteroidetes and Proteobacteria.
A substrate binds to an enzyme at the _______________, where the reaction occurs.
Active Site
The competitive inhibitor competes with the substrate for the _________________ on the enzyme
Active Site
You have an enzymatic reaction proceeding at the optimum pH and optimum temperature. You add a competitive inhibitor to the reaction and notice that the reaction slows down. What can you do to speed the reaction up again?
Add more substrate; it will outcompete the inhibitor and increase the reaction rate.
Which of the following statements describes a negative feedback response?
After a meal, blood sugar levels in the body rise; insulin is secreted to lower blood sugar levels.
Which of these is an example of negative feedback?
After you eat, insulin stimulates the lowering of blood sugar levels.
Which hormone functions in both the body's stress response and in the maintenance of salt and water balance?
Aldosterone
Which of the following statements about endocrine glands and the hormones they produce is true?
Aldosterone produced by the adrenal glands controls the reabsorption of sodium ions by the kidneys
Select the statement that is incorrect. Complex sugars are carbohydrates. All carbohydrates have the general formula Cn(H2O)nCn(H2O)n Simple sugars are carbohydrates. Simple sugars contain only carbon, oxygen, and hydrogen atoms.
All carbohydrates have the general formula Cn(H2O)nCn(H2O)n
Now, suppose that the three tomato genes from Part A did not assort independently, but instead were linked to one another on the same chromosome. Would you expect the phenotypic ratio in the offspring to change? If so, how? Which statement best predicts the results of the cross MmDdPp x mmddpp assuming that all three genes are linked?
All eight possible phenotypes could occur, but a greater proportion of the offspring would have the parental phenotypes.
What materials does DNA polymerase require in order to synthesize a complete strand of DNA?
All four deoxyribonucleotides triphosphates (containing A, C, T, or G) 3'-OH end of the new DNA strand Single-stranded DNA template
If an organism that is homozygous dominant is crossed with a heterozygote for that trait, the offspring will be __________.
All of the dominant phenotype
Which event or events occur during anaphase?
All of the listed responses are correct
An organ such as the heart or liver consists of __________.
All of the listed responses are correct.
Genomes of viruses may consist of which of the following types of nucleic acids?
All of the listed responses are correct.
Glucose is the primary fuel for cellular respiration. Which of the following molecules can also be used by cellular respiration to generate ATP?
All of the listed responses are correct.
Which of the following is a specific mechanism by which antibodies function in immunity?
All of the listed responses are correct.
Which of the following is not a disease caused by actions of the immune system?
All of the listed responses are correct.
Which of the following substances is generally filtered from the blood by the kidneys?
All of the listed responses are correct.
Which of the following structures is/are part of the mitotic spindle?
All of the listed responses are part of the mitotic spindle
Why were many of the early experiments on DNA carried out on viruses and bacteria?
All of the responses are true.
Meiosis guarantees that in a sexual life cycle, offspring will inherit one complete set of chromosomes (and their associated genes and traits) from each parent. The transmission of traits from parents to offspring is called heredity. Another important aspect of meiosis and the sexual life cycle is the role these processes play in contributing to genetic variation. Although offspring often resemble their parents, they are genetically different from both of their parents and from one another. The degree of variation may be tremendous.
All of them are in the "BOTH" category
An alternative version of a gene is called a(n) __________.
Allele
Which of the following actions is not a function of the epithelium?
Allows the internal environment to alter its conditions to match those of the external environment.
Orange dye moves independently of purple dye
Always
Protein polymers are made up of___________________________ monomers.
Amino acid
Fetal cells may be removed along with fluid from the womb by a process known as __________.
Amniocentesis
_____ in carbon dioxide in your red blood cells, which causes _____ in pH, causes your breathing to speed up. See Concept 42.6 (Page)
An increase ... a drop
Which of the following is an example of vertical transmission of a virus in plants?
An infected plant produces seeds that contain the virus, giving rise to infected progeny.
Which of the following correctly states the relationship between anabolic and catabolic pathways?
Anabolic pathways synthesize more complex organic molecules using the energy derived from catabolic pathways.
_____ are the main male hormones.
Androgens
In Klinefelter syndrome, individuals are phenotypically male, but have reduced sperm production and may have some breast development in adolescence. The cells of Klinefelter individuals have two X chromosomes and one Y (they are XXY instead of XY). This occurs because of what meiotic error?
Aneuploidy
RNA molecules that function as enzymes are called __________.
ribozymes
From the superior vena cava, blood flows to the _____.
right atrium
The lytic cycle of bacteriophage infection ends with the _____.
rupture of the bacterium
The acidity of the stomach contents triggers the small intestine to secrete a hormone known as _____.
secretin
The ability to observe meiosis in gamete production supported Mendel's first law of __________, which applies when __________ separate, and supported Mendel's second law of __________, which applies when __________ sort __________.
segregation; homologous pairs; independent assortment; alleles; independently
The thermostat is a _____________ that detects the stimulus and triggers a response.
sensor
This heating system maintains room temperature at or near a particular value, known as the
set point
Genetic diversity requires ____________
sexual reproduction, independent assortment, crossing over between nonsister chromatids of homologous chromosomes, and random fertilization
Replication of the lagging strand of DNA is accomplished by repeatedly making __________ followed by 1,000-2,000 nucleotide segments called __________.
short RNA primers; Okazaki fragments
In eukaryotic cells, a __________ by a __________ targets a growing peptide to the endoplasmic reticulum.
signal peptide; signal-recognition particle
What type of epithelial tissue, found in the intestines, absorbs nutrients?
simple columnar epithelium
What type of epithelial tissue lines kidney tubules?
simple cuboidal cells
Which of these tissues, found in the lungs, permits gas exchange by diffusion?
simple squamous epithelium
The genetic material of HIV consists of _____.
single-stranded RNA
The genetic material of HIV consists of __________
single-stranded RNA
Class IV viruses are characterized by which of the following types of genomes?
single-stranded RNA that serves as mRNA
In humans, most nutrient molecules are absorbed by the _________
small intestine
Why is it ineffective to treat viral disease with antibiotics?
Antibiotics inhibit enzymes specific to bacteria and have no effect on virally encoded enzymes.
Which secretion is not a barrier that prevents pathogens from entering the body?
Antigens
The function of the mitotic cell cycle is to produce daughter cells that __________.
Are genetically identical to the parent cell (assuming no mutation has occurred)
Sister chromatids differ from nonsister chromatids in that sister chromatids __________.
Are products of the S phase of the cell cycle and are two copies of one chromosome
As the chromosomes of a parent cell are duplicated and distributed to the two daughter cells during cell division, the structure of the chromosomes changes. Answer the three questions for each phase of the cell cycle by dragging the yes and no labels to the appropriate locations in the table. Note: Assume that by the end of the M phase, the parent cell has not yet divided to form two daughter cells.
Are sister chromatid present in all or part of this phase? G1-no S-yes G2-yes Beginning of M-yes End of M-no Is the DNA condensed in all or part of this phase? G1- no S-no G2-no Beginning of M-yes End of M-yes Does the cell contain twice as much DNA in this phase as it did in the G1 phase? G1- no S-yes G2-yes Beginning of M- yes End of M-yes
Consider a diploid cell where 2n = 6. During metaphase I of meiosis, as the pairs of homologous chromosomes line up on the metaphase plate, each pair may orient with its maternal or paternal homolog closer to a given pole. There are four equally probable arrangements of the homologous pairs at metaphase I. (Note that this problem assumes that no crossing over has occurred.) The cells below show the eight possible combinations of chromosomes that the daughter cells of meiosis II can receive.
Arrangement 1: 3 and 8 Arrangement 2: 1 and 5 Arrangement 3: 2 and 6 Arrangement 4: 4 and 7
How many nucleotides are needed to code for a protein with 450 amino acids?
At least 1,350
At low temperatures, a particular enzyme catalyzes a reaction, but at a slow rate. At high temperatures, the enzyme is completely inactive. What statement best explains the difference in how temperature affects the function of this enzyme?
At low temperatures, there is not enough free energy for the enzyme to function at a high rate, and at high temperatures, the enzyme is denatured, leaving it nonfunctional.
During aerobic respiration, molecular oxygen (O2) is used for which of the following purposes?
At the end of the electron transport chain to accept electrons and form H2O
Which of the following has an effect on blood pressure that counters the effect of the hormone aldosterone?
Atrial natriuretic peptide
Filtrate is formed as fluid is forced through the walls of the glomerulus and, initially, collects in the structure indicated by the letter
B
In the accompanying image, a nucleotide is indicated by the letter _____.
B
Which letter indicates diastolic pressure?
B
Which of these groups plays a major role in energy transfer?
B
Which of these is a phosphate group?
B
Which of these gametes contains one or more recombinant chromosomes?
B and C
Which of the following cell types carries out humoral immunity?
B cells
Clonal selection is the division of _____ that have been stimulated by binding to an antigen, which results in the production of cloned _____.
B cells ... plasma cells and memory cells
In all cells, separation of replicated chromosomes is a prerequisite for cell division. However, the mechanism of chromosome separation in bacteria is distinct from that in eukaryotes in several ways. Sort the following statements into the appropriate bin.
Bacteria only: chromosome separation begins at the origin of replication on DNA Eukaryotes only: Before separation duplicated chromosomes condense Nuclear envelope fragments permitting chromosome separation Two copies of the duplicated chromosome are attached at their centromeres before separating Both Bactria and eukaryotes: Chromosomes replicate before cell division; Replicated chromosomes separate by attaching to some other structural feature of the cell
Who formulated the one gene-one enzyme hypothesis?
Beadle and Tatum
Which of the following statements correctly describes the difference(s) between mitosis and binary fission?
Binary fission involves the replication and division of a single chromosome, whereas mitosis involves the division of multiple, replicated chromosomes.
Which of the following animals is paired with the correct excretory system unit?
Bird; kidney
_______________ is the connective tissue specialized for transport.
Blood
What is the source of the filtrate produced in Bowman's capsule?
Blood in capillaries
Which of the following occurs when body temperature decreases below normal body temperature?
Blood vessels in the skin constrict to help prevent heat loss.
An animal would lose water to its environment through osmosis under which set of conditions?
Body fluids of 400 mOsm/L in an environment of 1,000 mOsm/L
Which of the six major types of connective tissue has a rigid matrix that contains collagen and calcium salts?
Bone
Covalent bonds hold atoms together because they ... (a) fill shells without giving atoms much charge. (b) bring electrons closer to protons. (c) use forces between nuclei as well as forces between electrons. (d) both (a) and (b)
Both A and B
Which statement helps to explain why ice is less dense than liquid water? (a) Water molecules make hydrogen bonds at definite angles. (b) Cold molecules move less than warm molecules. (c) Hydrogen bonds lengthen in the cold. (d) Both A and B
Both A and B
Someone infected by chicken pox as a child is unlikely to suffer from this disease a second time. This is due to immunological memory, a reservoir of what type of cells that were generated following the initial exposure?
Both T cells and B cells
Which of the following statements correctly describes cofactors and coenzymes?
Both are nonprotein enzyme helpers; but most cofactors are metal ions, and coenzymes are organic molecules that are a specific type of cofactor.
How would anaerobic conditions (when no O2 is present) affect the rate of electron transport and ATP production during oxidative phosphorylation? (Note that you should not consider the effect on ATP synthesis in glycolysis or the citric acid cycle.
Both electron transport and ATPATP synthesis would stop.
Which of the following are common traits of chloroplasts and mitochondria?
Both have their own DNA.
What is the correct path of filtrate through a nephron of the kidney as it is processed into urine?
Bowman's capsule, proximal tubule, descending limb of loop Henle, thin segment of ascending limb, thick segment of ascending limb, distal tubule, collecting duct
How does ATP drive mechanical work inside a cell?
By binding to motor proteins
How does ATP drive transport work inside a cell?
By phosphorylating a transport protein
A nitrogenous base is indicated by the letter _____.
C
Which of these is a carbonyl group?
C
Which of these is reverse transcriptase?
C
Which of these is(are) pyrimidines?
C, D, and E
All of the following animals use extracellular digestion except _______.
sponges
DNA is transcribed to messenger RNA (mRNA), and the mRNA is translated to proteins on the ribosomes. A sequence of three nucleotides on an mRNA molecule is called a codon. As you can see in the table, most codons specify a particular amino acid to be added to the growing protein chain. In addition, one codon (shown in blue) codes for the amino acid methionine and functions as a "start" signal. Three codons (shown in red) do not code for amino acids, but instead function as "stop" signals. Use the table to sort the following ten codons into one of the three bins, according to whether they code for a start codon, an in-sequence amino acid, or a stop codon.
start/methionine: AUG stop codon: UAA ; UAG ; UGA amino acid: AUC ; UGC ; ACU ; AAA ; CAC ; GCA
You now know that inheritance of eye color in fruit flies is sex-linked: The gene encoding eye color is located on the X chromosome, and there is no corresponding gene on the Y chromosome. How would the inheritance pattern differ if the gene for eye color were instead located on an autosome (a non-sex chromosome)? Recall that for autosomes, both chromosomes of a homologous pair carry the same genes in the same locations. Suppose that a geneticist crossed a large number of white-eyed females Case 1: Eye color exhibits sex-linked inheritance. Case 2: Eye color exhibits autosomal (non-sex-linked) inheritance. (Note: In this case, assume that the red-eyed males are homozygous.) For each case, predict how many of the male and female offspring would have red eyes and white eyes.Drag the correct numbers on the left to complete the sentences on the right. Numbers can be used once, more than once, or not at all.
CASE 1: Eye color exhibits sex-linked inheritance1. If there were 100 female offspring, 100 would have red eyes and 0 would have white eyes.2. If there were 100 male offspring, 0 would have red eyes and 100 would have white eyes. CASE 2: Eye color exhibits autosomal (non-sex-linked) inheritance3. If there were 100 female offspring, 100 would have red eyes and 0 would have white eyes.4. If there were 100 male offspring, 100 would have red eyes and 0 would have white eyes.
A simple sugar is composed of equal parts carbon and water, which gave rise to the general name of any sugar as a ___________________________ .
Carbohydrate
Choose the correct statement from the list below.
Carbohydrate digestion begins in the mouth with salivary amylase.
For which of the following molecules does chemical digestion begin in the mouth?
Carbohydrates
An enzyme is considered a _____________ because it speeds up chemical reactions without being used up.
Catalyst
Which of the following choices correctly matches a tool and its proper application? transmission electron microscopy (TEM) to study the surfaces of preserved cells light microscopy to study the internal structure of cilia cell fractionation to study the function of specific organelles transmission electron microscopy (TEM) to study the movement of organelles within a living cell scanning electron microscopy (SEM) to study the detailed movements of living cells
Cell fractionation to study the function of specific organelles
Which of the following lists of animal structures is ordered from smallest to largest?
Cell, tissue, organ, organ system
Which of the following is a benefit of multicellularity compared to organisms consisting of just one cell?
Cells can specialize.
What is the difference between a benign tumor and a malignant tumor?
Cells of benign tumors do not metastasize; those of malignant tumors do.
In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?
Cellular respiration
Mutualistic microorganisms living in herbivore alimentary canals help herbivores digest ________.
Cellulose
Which of these is a polysaccharide? sucrose cellulose glucose galactose lactose
Cellulose
_____________ is the most abundant organic compound on Earth.
Cellulose
After chromosomes condense, the ____________________ is the region where the identical DNA molecules are most tightly attached to each other.
Centromere(s)
The ____________________ are the organizing centers for microtubules involved in separating chromosomes during mitosis.
Centrosome(s)
Which of the following statements is an accurate description of external effects on hormones?
Certain molecules in the environment can function like hormones or block the actions of hormones.
Mendel studied __________, heritable features that vary among individuals; each variant is called a __________.
Characters, trait
During interphase, most of the nucleus is filled with a complex of DNA and protein in a dispersed form called _________________.
Chromatin
The complex of DNA and protein that makes up a eukaryotic chromosome is properly called __________.
Chromatin
Which of the following organ systems in mammals is mismatched with its function?
Circulatory; coordination of body activities
Which of the following pairs of pathways and their location in the cell is incorrectly matched?
Citric acid cycle: cytosol
Cytochalasin B is a chemical that disrupts microfilament formation. How would this interfere with cell division? See Concept 12.2 (Page)
Cleavage
Which of the following is a post-translational modification of a polypeptide?
Cleavage of a polypeptide into two or more chains
__________ are a group of genetically identical individuals produced by a process called __________.
Clones; asexual reproduction
In addition to the ABO system, humans have other blood groups, including the MN system. Individuals who have alleles for both M and N show __________ for the M and N red blood cell surface antigens.
Codominance
A red bull is crossed with a white cow and all of the offspring are roan, an intermediate color that is caused by the presence of both red and white hairs. This is an example of genes that are __________.
Codominant
A _________________, such as a vitamin, binds to an enzyme and plays a role in catalysis.
Cofactor
A(n) ___________________ inhibitor has a structure that is so similar to the substrate that it can bond to the enzyme just like the substrate.
Competitive
Which of the following statements is correct regarding competitive and noncompetitive enzyme inhibitors?
Competitive inhibitors bind to the active site of an enzyme while noncompetitive inhibitors bind to an enzyme away from the active site.
Duplication of chromosomes occurs during S phase of the cell cycle. Duplication requires the separation of complementary DNA strands to allow for DNA replication. Which of the following statements best explains how weak hydrogen bonds function better in this situation than stronger bonds would?
Complementary DNA strands are separated or "unzipped" for the replication process. Weak hydrogen bonds between complementary strands are easily disrupted during DNA replication because they are not high-energy chemical bonds.
When properly aligned, the enzyme and substrate form an enzyme-substrate (ES)_________________.
Complex
is a multi-protein complex within the electron transport chain.
Complex III
How does connective tissue differ from the other three major tissue types?
Connective tissue often consists of relatively few cells embedded in an extracellular matrix.
Which of the following is the main factor that causes lymph to move through lymphatic vessels?
Contractions of body muscles near lymph vessels
The ATP that is generated in glycolysis is produced by substrate-level phosphorylation, a very different mechanism than the one used to produce ATP during oxidative phosphorylation. Phosphorylation reactions involve the addition of a phosphate group to another molecule. Sort the statements into the appropriate bin depending on whether or not they correctly describe some aspect of substrate-level phosphorylation in glycolysis.
Correct: -One of the substrates is a molecule derived from the breakdown of glucose -An enzyme is required in order for the reaction to occur -A bond must be broken between an organic molecule and phosphate before ATP can form. Incorrect: -The phosphate group added to ADP to make ATP comes from free inorganic phosphate ions. -The enzyme's involved in ATP synthesis must be attached to a membrane to produce ATP.
Which of the following maximizes gas exchange in the gills of a bony fish?
Countercurrent exchange
How could the botanist best determine whether the genotype of the green-pod plant is homozygous or heterozygous?
Cross the green-pod plant with a yellow-pod plant.
Which processes lead to most genetic variation in sexually reproducing organisms?
Crossing over independent assortment of chromosomes in meiosis random fertilization
In animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle?
Cytokinesis
In most eukaryotes, division of the nucleus is followed by _____________________, when the rest of the cell divides.
Cytokinesis
Which letter indicates the arteries?
D
Which of these functional groups is characteristic of alcohol?
D
Which of these is a hydroxyl group?
D
You open the window, and a blast of icy air enters the room. The temperature drops to 17 degrees Celsius, which acts as a _____________ to the heating system.
stimulus
What type of epithelium would you expect to find covering a surface subject to physical forces?
stratified epithelium
These molecules are _____.
structural isomers
The parent cell that enters meiosis is diploid, whereas the four daughter cells that result are haploid. Which statement correctly describes how cellular DNA content and ploidy levels change during meiosis I and meiosis II?
DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.
Which of these is a difference between a DNA and an RNA molecule?
DNA is usually double-stranded, whereas RNA is usually single-stranded.
What appears to be the mechanism for genomic imprinting?
DNA methylation that silences particular genes and DNA methylation that activates particular genes
Can you match these prefixes, suffixes, and word roots with their definitions? under, below:
sub-
In bacterial DNA replication of the lagging strand, __________ is required for the synthesis of a new DNA strand whereas __________ is required for removing the RNA primer and replacing it with DNA nucleotides.
DNA polymerase III; DNA polymerase I
What is the role of DNA polymerase during DNA synthesis?
DNA polymerase is the enzyme that catalyzes the addition of a nucleotide onto the 3' end of a growing DNA strand.
When two amino acid monomers are positioned so that the carboxyl group of one is adjacent to the amino group of the other, they can be joined through a ________________ reaction. This reaction forms a(n) _______________ bond.
Dehydration, peptide
An enzyme is _______________ when it loses its native conformation and its biological activity
Denatured
In which of the following portions of a nephron of the mammalian kidney does the filtrate have the highest osmolarity?
Descending limb of the loop of Henle in the inner medulla
The regions of the nephron through which filtrate flows are labeled in the figure below. Drag each statement to the appropriate bin depending on whether it applies to the descending limb of the loop of Henle, the ascending limb of the loop of Henle, or the collecting duct.
Descending limb of the loop of Henle: --numerous aquaporins (water channels) but almost no ion channels --no energy required for transport --epithelium always permeable to water Ascending limb of the loop of Henle: --no aquaporins (water channels) --passive transport of NaCl in the thin segment and active transport of NaCl in the thick segment Collecting duct: --hormones control permeability to water and transport of NaCl --active transport of NaCl associated with loss of water from filtrate
Why do larger animals, such as a bullfrog, require a circulatory system, but animals such as a planarian do not?
Diffusion is inadequate to move gases through the body surface and into all parts of a larger animal body. However, diffusion alone is sufficient to move gases in and out of the thin body of a planarian.
Lactose, the sugar in milk, is a __________________, because it can be split into two monosaccharides.
Disaccharide
Cytokinesis refers to __________.
Division of the cytoplasm
Regarding the role of cohesin protein in maintaining cohesion between sister chromatids, which of the following statements is false?
During meiosis II, cohesion holds sister chromatids together along their lengths as the second meiotic spindle forms.
The urethra is identified by the letter _____.
E
Which letter indicates the vessels in which blood velocity is decreasing the most due to an increase in the total combined cross-sectional area of those vessels?
E
Which of these groups is characteristic of thiols?
E
Which of these is the viral genome?
E
Ribosomes provide the scaffolding on which tRNAs interact with mRNA during translation of an mRNA sequence to a chain of amino acids. A ribosome has three binding sites, each of which has a distinct function in the tRNA-mRNA interactions Drag the appropriate tRNAs to the binding sites on the ribosome to show the configuration immediately before a new peptide bond forms. Note that one of the binding sites should be left empty.
E- site empty P- site AUA with three amino acids A- site UCC with one amino acid
As a researcher in a protein lab, you analyze two different proteins for their shape and the amino acids they contain. Your results show that the two proteins have exactly the same numbers and types of amino acids, but they have different shapes. What is the best explanation for these results?
Each protein has a unique linear sequence of amino acids.
Who is credited with performing the first documented immunization?
Edward Jenner
Queen Victoria was a carrier of a recessive sex-linked allele for hemophilia. Which of the following possibilities could explain the presence of the hemophilia allele in her genotype?
Either her mother was a carrier or her father had hemophilia
Fermentation is essentially glycolysis plus an extra step in which pyruvate is reduced to form lactate or alcohol and carbon dioxide. This last step __________.
Enables the cell to recycle the reduced NADH to oxidized NAD+
Which of the following systems is correctly paired with one of its parts?
Endocrine system; thyroid gland
Which of the following would be most likely to increase for an amphibian moving from the aquatic habitat it occupies as a larva to the terrestrial habitat it occupies as an adult?
Energetic cost of excretion
Which of the following states the relevance of the first law of thermodynamics to biology?
Energy can be freely transformed among different forms as long as the total energy is conserved.
"Conservation of energy" refers to the fact that _____.
Energy cannot be created or destroyed but can be converted from one form to another
If the entropy of a living organism is decreasing, which of the following is most likely to be occurring simultaneously?
Energy input into the organism must be occurring to drive the decrease in entropy.
Proteins perform a variety of functions in living organisms. The protein lysozyme (shown in the figure) is found in tears and saliva where it prevents infection by catalyzing the destruction of specific molecules on the surface of many kinds of bacteria. To which functional class of proteins does lysozyme belong?
Enzymatic protein
When the noncompetitive inhibitor is bonded to the enzyme, the shape of the ________________ is distorted.
Enzyme
Which of the following statements about enzyme function is correct?
Enzymes can lower the activation energy of reactions, but they cannot change the equilibrium point because they cannot change the net energy output.
Which of the following statements about enzymes is true?
Enzymes speed up the rate of the reaction without changing the ΔG for the reaction.
Which of the following hormones is thought to act at the cellular level by inducing a change in gene expression?
Estrogen
Darwin realized the importance of heritable variation to evolution __________.
Even though he never read any of Gregor Mendel's work
Chloride cells in the gills of marine bony fishes play a role in which step of excretory system function?
Excretion
Which process is not required for an animal to obtain energy from food?
Excretion.
The primary manner in which cells manage their energy resources in order to do work is called energy coupling. Which of the following statements accurately defines energy coupling?
Exergonic reactions drive endergonic reactions.
The function of cellular respiration is to __________.
Extract usable energy from glucose
Which letter indicates the vessels in which blood travels the most slowly?
F
Which of functional groups listed below behaves as an acid?
F
Which of these is a carboxyl group?
F
Of the following lists of electron transport compounds, which one lists them in order from the one containing electrons with the highest free energy to the one containing electrons with the lowest free energy? Note that not all electron transport compounds in the electron transport chain are listed
FADH2 -- Fe-S of Complex II -- Q -- Fe-S of Complex III -- Cyt c -- Cyt a of Complex IV -- O2
If a mitochondrion ran out of molecular oxygen (O2), predict which of the following situations would occur in its electron transport chain.
FMN prosthetic groups would remain reduced and NADH would have nowhere to donate electrons.
You decide to designate the twist allele as FT to distinguish it from the forked allele F. Using the following allele symbols, identify the genotypes of the three F2 classes in Part C by dragging one label to each class. Labels may be used once, more than once, or not at all.
F^(T)F^(T) FF FF^(T)
(T/F) Crossing over prevents homologous chromosomes from separating during meiosis I.
False
(True of False) Regulated changes in the epithelium of the loop of Henle allow the kidney to operate in water-conservation mode.
False
(True or False) The collecting duct concentrates urine by actively reabsorbing NaCl
False
The -OH group on the 3' carbon of the sugar unit is the attachment site for the nitrogenous base. (T/F)
False
The antiparallel arrangement of double-stranded DNA is due to the phosphate group being bonded to the 3' carbon on one strand and the 5' carbon on the complementary strand (T/F)
False
The words "antigen" and "virus" are interchangeable.
False
True or False? The liver is a component of the alimentary canal.
False
True or false? One advantage of having a tube-like digestive tract is that digestion of all compounds can take place simultaneously down the tract.
False
True or false? The circulatory systems of land-dwelling vertebrates are composed of two pumping circuits: the systemic circulation, which is a lower-pressure circuit to the lung, and the pulmonary circulation, which is a higher-pressure circuit to the rest of the body.
False
True or false? The leukocytes of the innate immune system are B cells, macrophages, and neutrophils.
False
DDT is _____-soluble so it accumulates in _____.
Fat, milk
is a prosthetic group present in several components of the electron transport chain.
Fe -S
ATP allosterically inhibits enzymes in ATP-producing pathways. The result of this is called __________.
Feedback inhibition
Cells must regulate their metabolic pathways so that they do not waste resources. What is the most common mechanism that regulates cellular respiration in most cells?
Feedback inhibition of glycolysis
Fermentation by itself produces no ATP but keeps glycolysis going, which produces a small amount of ATP. How does fermentation do this?
Fermentation oxidizes NADH to NAD+, which facilitates the production of ATP in glycolysis.
NADH and FADH2 are both electron carriers that donate their electrons to the electron transport chain. The electrons ultimately reduce O2 to water in the final step of electron transport. However, the amount of ATP made by electrons from an NADH molecule is greater than the amount made by electrons from an FADH2 molecule. Which statement best explains why more ATP is made per molecule of NADH than per molecule of FADH2?
Fewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron donor.
Examine the human gut microbiome at different life stages. Locate the pie chart showing the microbiome of a healthy adult's intestinal tract. Which statement best represents the bacterial community composition of a healthy adult's intestinal tract?
Firmicutes are the most abundant bacteria in the intestinal tract of healthy adults, followed by Bacteroidetes and a small amount of Actinobacteria and Proteobacteria.
Place the events in the transcription of a gene in their proper order from left (first event) to right (last event).Rank from first event to last event.
First Event -> Last Event (First) RNA polymerase binds promoter. RNA polymerase transcribes gene. RNA polymerase reaches terminator. (Last) RNA polymerase exits gene, RNA is released.
_______________________ is a vitamin that is used in reactions that transfer single-carbon units. The vitamin also helps reduce the risk of birth defects such as spina bifida and cleft lip. Women of child-bearing age should consume the recommended amount of this vitamin.
Folic acid
What is the result when a diploid cell undergoes meiosis?
Four haploid cells
X-ray diffraction images produced by __________ showed that DNA is a __________.
Franklin; double helix
Choose the correct statement from the list below.
Free fatty acid absorption occurs in the small intestine.
During osmosis, water diffuses across a selectively permeable membrane from the region of higher ________________________ concentration and lower _______________concentration to the side with lower _______________________concentration and higher ______________concentration.
Free water, solute, free water, solute
A life cycle in which the only multicellular form is haploid is most typical of __________.
Fungi
Which letter indicates the venules?
G
Cells will usually divide if they receive the proper signal at a checkpoint in which phase of the cell cycle? See Concept 12.3 (Page)
G1
_____ aid in the coordination of the activities of adjacent animal cells.
Gap (communicating) junctions
The chromosome theory of inheritance states that __________.
Genes occupy specific positions on chromosomes, homologous chromosomes segregate from each other during meiosis, and chromosomes assort independently during meiosis
Allelic variation is an important source of __________ in a population.
Genetic diversity
Which of the following reactions would be endergonic?
Glucose + fructose → sucrose
During the energy investment phase of glycolysis, __________.
Glucose is phosphorylated before it is split into two three-carbon molecules
Under anaerobic conditions (a lack of oxygen), glycolysis continues in most cells despite the fact that oxidative phosphorylation stops, and its production of NAD+ (which is needed as an input to glycolysis) also stops. The diagram illustrates the process of fermentation, which is used by many cells in the absence of oxygen. In fermentation, the NADH produced by glycolysis is used to reduce the pyruvate produced by glycolysis to either lactate or ethanol. Fermentation results in a net production of 2 ATP per glucose molecule. During strenuous exercise, anaerobic conditions can result if the cardiovascular system cannot supply oxygen fast enough to meet the demands of muscle cells. Assume that a muscle cell's demand for ATP under anaerobic conditions remains the same as it was under aerobic conditions. What would happen to the cell's rate of glucose utilization?
Glucose utilization would increase a lot.
Several days after a long holiday weekend including much overeating, you try to cut back on your calories. The first day that you reduce your calorie intake to below the levels that you need, your body will respond by using __________
Glycogen from the liver
In which process is glucose oxidized to form two molecules of pyruvate?
Glycolysis
Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?
Glycolysis
Each of the four stages of cellular respiration occurs in a specific location inside or outside the mitochondria. These locations permit precise regulation and partitioning of cellular resources to optimize the utilization of cellular energy.
Glycolysis - Cytosol Acetyl CoA - Mitochondrial matrix Citric acid cycle - Mitochondrial matrix Oxidative phosphorylation - inner mitochondrial membrane
How does a retrovirus like HIV enter a host cell?
Glycoproteins on the viral envelope bind to receptors on the host cell. The viral envelope fuses with the host cell's plasma membrane, facilitating uptake of the virus by the host cell.
In which of the following animals are the blood and the interstitial fluid considered to be the same body fluid? See Concept 42.1 (Page)
Grasshoppers
The scientists also graphed the H1N1 isolates by the month and year of isolate collection, which reflects the time period in which each viral variant was actively causing illness in people. Select Figure 2 from the drop-down menu above the phylogenetic tree (Figure 2). The graph shows the number of isolates collected from ill patients (one isolate per patient) on the y-axis and the month and year that the isolates were collected on the x-axis. Each group of variants is plotted separately with a line color that matches the phylogenetic tree diagram. Which group of variants was the earliest to cause H1N1 flu in over 100 patients in Taiwan?
Group 7 (black line)
Which letter indicates the vessels in which blood velocity is increasing the most due to a decrease in the total combined cross-sectional area of those vessels?
H
Most of the ATP in cellular respiration is produced by the process of chemiosmosis. How does this process produce ATP?
H+ flows across the inner mitochondrial membrane through the enzyme ATP synthase.
How do hydrogen ions (H+) and chloride ions (Cl-) get into the lumen of the stomach?
H+ is actively transported from parietal cells into the lumen, while Cl- diffuses from parietal cells into the lumen.
A man who has been exposed to the flu virus is tested by his physician. The physician notes that the virus is present but no measurable level of antibodies corresponding to the virus are detected in his body. What might this mean?
He was probably exposed a few days ago and clonal selection has yet to produce plasma cells.
Which description of DNA replication is correct?
Helicases separate the two strands of the double helix, and DNA polymerases then construct two new strands using each of the original strands as templates.
___________ interact with the antigen-class II MHC complex presented by macrophages.
Helper T cells
________ mainly eat plants and algae, and ________ mainly eat other animals
Herbivores; carnivores
Why can flare-ups of herpes virus infection recur throughout a person's life?
Herpes virus can leave its DNA behind as minichromosomes in nerve cell nuclei. Stress can trigger another round of virus production, producing characteristic blisters and sores.
How is the level of thyroxine in the blood regulated?
High levels of T3 and T4 inhibit the secretion of TRH and TSH.
Enzyme activity is affected by pH because __________.
High or low pH may disrupt hydrogen bonding or ionic interactions and thus change the shape of the active site
A man who can roll his tongue and a woman who cannot roll her tongue have a son who can roll his tongue (R = can roll tongue; r = can't roll tongue). The son is curious about whether his father is homozygous or heterozygous for the tongue-rolling trait. Which of the following facts would allow him to know?
His father's mother cannot roll her tongue.
Which of the following statements is an accurate description of the function of hormones in homeostasis?
Homeostasis in humans is maintained by many of the same hormones that have regulatory roles in other animals.
A pair of genetic structures carrying genes that control the same inherited characters are called __________.
Homologous chromosomes
How are sister chromatids and homologous chromosomes different from each other? See Concept 13.3 (Page)
Homologous chromosomes contain the same gene loci but may have different alleles of a particular gene. Sister chromatids are identical copies of each other produced during DNA replication.
Which of the following occurs in meiosis, but not mitosis?
Homologous chromosomes separate.
Which of the following statements is an accurate description of the regulation of the endocrine system?
Hormone pathways are regulated by both positive- and negative-feedback loops.
Which of the following statements correctly describes a difference between hormone signaling and neuron signaling?
Hormone signals travel throughout the body, but neuron signals travel to specific locations.
Acquired immunity involves both a humoral immune response and a cell-mediated immune response. To review the definitions of these immune responses, see Hint 1. Sort the items into the appropriate bins depending on whether they are involved in the humoral response, the cell-mediated response, or both the humoral and the cell-mediated responses. (If you are not sure what some of the items are, see Hint 2.)
Humoral response: -B cells -Plasma cells -Antibodies Cell-minded response: -Cytotoxic T cells Both: -Helper T cells and cytokines -Memory cells -Antigen-presenting cells
What is the arrow pointing to?
Hydrogen ion
What holds phospholipids together in a bilayer formation?
Hydrophilic and hydrophobic interactions with water
What is the arrow pointing to?
Hydroxide ion
You can tell that this is an image of a DNA nucleotide and not an RNA nucleotide because you see a _____.
sugar with two, and not three, oxygen atoms
Each of the following phrases describes the structure, function, or regulation of either the hypothalamus, posterior pituitary, or anterior pituitary. Sort the phrases into the appropriate bins depending on whether they describe the hypothalamus, posterior pituitary, or anterior pituitary.
Hypothalamus: --integrates nervous and endocrine systems --synthesizes oxytocin and ADH Posterior pituitary: --is an extension of the hypothalamus --releases oxytocin and ADH Anterior pituitary: --regulated by hormones released into portal blood vessels --synthesizes and releases TSH --synthesizes and releases PRL
Pedigree 2 from Part A is shown below. Recall that this pedigree shows the inheritance of a rare, autosomal dominant condition. Fill in the genotypes for the indicated individuals in the pedigree by dragging the best label to the appropriate location. Labels can be used once, more than once, or not at all.
I- Dd II- Dd, dd, Dd III- dd, Dd, dd
Pedigree 3 from Part A is shown below. Recall that this pedigree shows the inheritance of a rare, autosomal recessive condition. Note that individual II-3 has no family history of this rare condition. Fill in the genotypes for the indicated individuals in the pedigree by dragging the best label to the appropriate location. Labels can be used once, more than once, or not at all.
I- rr II- Rr, RR, Rr III- R_, R_, R_
Which of the following classes of immunoglobins crosses the placenta and confers passive immunity to the fetus?
IgG
What is a key difference in gene expression between eukaryotic and prokaryotic cells?
In prokaryotic cells, the mRNA transcript is immediately available as mRNA without processing.
Under anaerobic conditions (a lack of oxygen), the conversion of pyruvate to acetyl CoA stops. Which of these statements is the correct explanation for this observation?
In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration.
Consider a situation in which the enzyme is operating at optimum temperature and pHpH, and has been saturated with substrate. What is your best option for increasing the rate of the reaction?
Increase the enzyme concentration.
Which of the following factors would increase the release of oxygen from hemoglobin?
Increased exercise and decreased blood pH
You have probably noticed that urine is not always the same. The body is capable of adjusting the volume and the osmolarity of its urine output depending on a number of factors. The kidneys are regulated by hormones such as antidiuretic hormone (ADH) and aldosterone. These hormones are secreted in response to changes in the animal's internal water and salt balance. For example, sweating or blood loss can disrupt water and/or salt balance in the body, leading to a hormonal response that returns the system to homeostasis. Mechanisms for adjusting blood volume or osmolarity include increasing water and/or sodium reabsorption in the nephrons and collecting ducts. How do the following stimuli affect water and sodium (Na+) reabsorption in the kidneys? Drag each item to the appropriate bin.
Increases water reabsorption: -ADH secretion -Sweating -Eating salty food -Dehydration due to inadequate water intake Increases both water and Na+ reabsorption: -Aldosterone release -Blood loss -Severe diarrhea Does not increase water or Na+ reabsorption: -Alcohol consumption -Caffeine consumption -Diabetes insipidus
Which of the following have an excretory system that functions without a filtration step?
Insects
Every time you eat a cookie or candy bar, your blood sugar increases. This triggers an increase in the hormone __________.
Insulin
Which of the following is a pair of hormones that have antagonistic effects?
Insulin and glucagon
Which component of a homeostatic system compares sensory information to a target value?
Integrator
In dividing cells, most of the cell's growth occurs during _______________________
Interphase
Usually, a(n) ____________________ inhibitor forms a covalent bond with an amino acid side group within the active site, which prevents the substrate from entering the active site or prevents catalytic activity.
Irreversible
What is the function of a circulatory system?
It brings a transport liquid into close contact with all cells in the body.
What can happen to an electron when sunlight hits it?
It can stay in its original shell. It can move out to a higher electron shell
What is the function of reverse transcriptase?
It catalyzes the formation of DNA from an RNA template.
Think about the DNA coding sequence of a gene. If an A were swapped for a T, what kind of mutation could it cause and why?
It could cause a silent, missense, or nonsense mutation because those are the types that can be caused by a nucleotide-pair substitution like this one.
Which statement about the gas exchange system in fish is correct?
It enables oxygen to diffuse from the water into the blood over the entire length of the gill capillaries.
You would know a dividing cell was a plant cell rather than an animal cell if you saw that __________.
It had formed a cell plate
Which of these describes loose connective tissue?
It is a loose weave of fibers that functions as a packing material.
What is the fate of the phosphate group that is removed when ATP is converted to ADP?
It is acquired by a reactant in an endergonic reaction.
In the oxidation of pyruvate to acetyl CoA, one carbon atom is released as CO2. However, the oxidation of the remaining two carbon atoms—in acetate—to CO2 requires a complex, eight-step pathway—the citric acid cycle. Consider four possible explanations for why the last two carbons in acetate are converted to CO2 in a complex cyclic pathway rather than through a simple, linear reaction. Use your knowledge of the first three stages of cellular respiration to determine which explanation is correct.
It is easier to remove electrons and produce CO2 from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA.
What is unique about blood in pulmonary arteries compared with blood in other arteries?
It is loaded with carbon dioxide.
Select the correct statement about the process of scientific inquiry.
It is possible to test hypotheses, such as those involving historical events, without conducting experiments
Which of the following is not a characteristic of innate immunity?
It is present only in vertebrates.
What is the role of oxygen in the electron transport chain?
It is reduced to form water
What is one function of mucus in the lumen of the stomach?
It protects the epithelium from being digested by gastric juice.
What is the function of the left ventricle?
It pumps oxygenated blood around the body via the systemic circulation.
Which of the following statements is correct regarding kinetic and potential energy?
Kinetic energy is associated with the relative motion of objects, and potential energy is the energy that matter possesses because of its location or structure.
During mitosis, microtubules attach to chromosomes at the
Kinetochore(s)
Which statement correctly describes the difference between alcohol fermentation and lactic acid fermentation?
Lactic acid fermentation produces lactate, and alcohol fermentation produces ethanol.
How do cells involved in the innate immune response detect the presence of pathogens?
Leukocytes recognize unique molecules on pathogens.
Some solutes are able to pass directly through the lipid bilayer of a plasma membrane, whereas other solutes require a transport protein or other mechanism to cross between the inside and the outside of a cell. The fact that the plasma membrane is permeable to some solutes but not others is what is referred to as selective permeability. Which of the following molecules can cross the lipid bilayer of a membrane directly, without a transport protein or other mechanism? Select all that apply. lipids proteins carbon dioxide ions water sucrose oxygen
Lipids Carbon dioxide Water Oxygen
A molecule becomes more oxidized when it __________.
Loses an electron
Which of the following conditions in a silkworm moth would result in metamorphosis from pupa to adult?
Low concentration of juvenile hormone and high concentration of ecdysteroid
The figure shows how fats are absorbed from the lumen of the small intestine and ultimately reach the blood. Key events occur in the lumen, in small intestine epithelial cells, and in lacteals, which are vessels of the lymphatic system. Drag each statement into the appropriate bin depending on whether the event occurs in the lumen of the small intestine, in a small intestine epithelial cell, or in a lacteal.
Lumen of small intestine: -Lipase breaks triglycerides down into monoglycerides and fatty acids. Epithelial cell: - Chylomicrons leave this structure by exocytosis. -Monoglycerides and fatty acids are reassembled to form triglycerides. -Triglycerides are coated with phospholipids, cholesterol, and proteins to form chylomicrons. Lacteal: -This structure contains lymph. -Chylomicrons are transported in this structure to veins.
Which of the following would not normally pass into a nephron of the kidney as a component of the filtrate?
Lymphocytes
Classify each phrase as applying to the lytic cycle, the lysogenic cycle, or both types of reproductive cycles of phages. Drag the descriptions into the appropriate bins.
Lytic Cycle - the cell is lysed (broken open), -new phages are assembled from viral DNA ad proteins, -the host is destroyed Lysogenic Cycle - the cell reproduces normally, -the viral DNA integrates into the chromosome of the host cell Both Cycles -viral genes are replicated
Tissues are immunogically "typed" before an organ transplant to make sure that the donor and recipient match as closely as possible in their _____. See Concept 43.3 (Page)
MHC (major histocompatibility complex) proteins
When searching for a donor for an organ transplant, doctors try to match the __________ of the donor and recipient as closely as possible.
MHC proteins
Which of the following cells are part of the innate, second line of defense?
Macrophages
Besides helper T cells, what are two other types of cells that HIV infects?
Macrophages and brain cells
Which of the following cells can engulf a pathogen?
Macrophages.
In a certain fish, fin rays (supporting structures for the fins) can be either bony or soft in adult fish. Sex linkage in a fish is similar to that in humans. What evidence would most strongly support the idea that the ray locus is on the X chromosome?
Matings of soft ray males and bony ray females give different results from the matings of bony ray males and soft ray females.
The process called __________ reduces the chromosome number by __________.
Meiosis; two consecutive cell divisions
Which of the following is not a tropic hormone?
Melanocyte-stimulating hormone (MSH)
Some viruses have membranous envelopes. Where do viral envelopes typically originate from?
Membranes from the host cell
During translation, nucleotide base triplets (codons) in mRNA are read in sequence in the 5' → 3' direction along the mRNA. Amino acids are specified by the string of codons. What amino acid sequence does the following mRNA nucleotide sequence specify? 5′−AUGGCAAGAAAA−3′ Express the sequence of amino acids using the three-letter abbreviations, separated by hyphens (e.g., Met-Ser-Thr-Lys-Gly).
Met-Ala-Arg-Lys
Before a molecule of mRNA can be translated into a protein on the ribosome, the mRNA must first be transcribed from a sequence of DNA. What amino acid sequence does the following DNA nucleotide sequence specify? 3′−TACAGAACGGTA−5′ Express the sequence of amino acids using the three-letter abbreviations, separated by hyphens (e.g., Met-Ser-His-Lys-Gly).
Met-Ser-Cys-His
Which of the following is true regarding metabolic pathways?
Metabolic pathways consist of a series of reactions, each catalyzed by a different enzyme.
The spread of cancer cells to other locations in the body is known as __________.
Metastasis
__________ are needed in the diet as components of teeth and bone, as parts of certain enzymes, for normal muscle and nerve function, and for water balance.
Minerals
A ___________________ mutation causes a wild-type amino acid to be replaced by a different amino acid.
Missense
The ________________________ is a cell structure consisting of microtubules, which forms during early mitosis and plays a role in cell division.
Mitotic spindle(s)
A(n) _____ refers to two or more atoms held together by covalent bonds.
Molecule
A ___________________ cannot be hydrolyzed any further.
Monosaccharide
How is the stomach lining protected from the strongly acidic pH of its contents?
Mucous cells secrete a protective lubricant into the stomach.
Which life cycle stage is found in plants but not animals?
Multicellular haploid
Human ABO groups are best described as an example of __________.
Multiple alleles
Which of the following is a function of mitosis in humans?
Multiplication of body cells
B lymphocytes __________.
Multiply and make antibodies that circulate in blood and lymph
After completion of the citric acid cycle, most of the usable energy from the original glucose molecule is in the form of __________.
NADH
Donates electrons to the electron transport chain
NADH
What is the correct order of electron transport compounds from best electron donor to best electron acceptor?
NADH -- Fe-S of Complex I -- Q -- Fe-S of Complex III -- Cyt c-- Cyt a of Complex IV -- O2
During the energy payoff phase of glycolysis, __________.
NADH and ATP are produced
In what molecule(s) is the majority of the chemical energy from pyruvate transferred during the citric acid cycle?
NADH and FADH2
This osmolarity gradient is maintained by both the passive transport and the active transport of __________________
NaCl
Which of the following cells does not play a role in immunity through the phagocytosis of pathogens?
Natural killer cells
Animals that harbor and can transmit a particular virus but are generally unaffected by it are said to act as a __________ for that virus.
Natural reservoir
Using the figure to guide your response, select the best explanation for why natural selection might have resulted in the optimal pH for pepsin.
Natural selection favors enzymatic activity of pepsin at a pH of 2.0 because 2.0 is the pH inside the stomach.
__________ feedback most directly maintains homeostasis because it __________.
Negative; tends to keep a system at a desirable "set point"
From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of glycolysis. Drag each compound to the appropriate bin. If the compound is not involved in glycolysis, drag it to the "not input or output" bin.
Net Input: ADP, NAD⁺, Glucose Net Output: ATP, NADH and Pyruvate, Not input or output: O₂, CO₂, coenzyme A and acetyl CoA
In the citric acid cycle (also known as the Krebs cycle), acetyl CoA is completely oxidized. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of the citric acid cycle. Drag each compound to the appropriate bin. If a compound is not involved in the citric acid cycle, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of the citric acid cycle are included.)
Net Input: Acetyl CoA, NAD⁺, ADP Net Output: Coenzyme A, CO₂, NADH, ATP Not Input or Output: Pyruvate, Glucose, O₂
An exception to the one gene-one enzyme hypothesis is __________.
that not all genes code for enzymes; some genes code for structural proteins such as keratin
The term "true-breeding plants" means __________.
that self-pollinating plants will always produce the same trait of a particular character
Evidence to support that DNA strands run antiparallel to each other includes all of the following except __________.
that the sugar-phosphate backbones are to the inside of the molecule
DNA replication occurs in __________________
the S phase of interphase in both somatic and reproductive cells
Eukaryotic processing of the primary transcript includes __________.
the addition of a 5ꞌ cap, a 3ꞌ poly-A tail, and the splicing out of introns
In the last stage of cellular respiration, oxidative phosphorylation, all of the reduced electron carriers produced in the previous stages are oxidized by oxygen via the electron transport chain. The energy from this oxidation is stored in a form that is used by most other energy-requiring reactions in cells. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of oxidative phosphorylation. Drag each compound to the appropriate bin. If a compound is not involved in oxidative phosphorylation, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of oxidative phosphorylation are listed.)
Net Input: NADH, ADP, O₂ Net Output: NAD⁺, ATP, and Water Not Input or Output: Pyruvate, Glucose, Acetyl CoA, Coenzyme A and CO₂
Skeletal muscle is said to be "striated" because __________.
the arrangement of the sarcomeres gives it a striped appearance
During transcription in eukaryotes, a type of RNA polymerase called RNA polymerase II moves along the template strand of the DNA in the 3'→5' direction. However, for any given gene, either strand of the double-stranded DNA may function as the template strand. For any given gene, what ultimately determines which DNA strand serves as the template strand?
the base sequence of the gene's promoter
One event occurring during prophase is ________________
the beginning of the formation of a spindle apparatus
In acetyl CoA formation, the carbon-containing compound from glycolysis is oxidized to produce acetyl CoA. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of acetyl CoA formation. Drag each compound to the appropriate bin. If a compound is not involved in acetyl CoA formation, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of acetyl CoA formation are included.)
Net Input: NAD⁺, coenzyme A, pyruvate Net Output: NADH, acetyl CoA, CO₂ Not input or output: O₂, ADP, glucose and ATP
Which of the following statements about the pituitary gland is false?
Neurosecretory cells produce hormones that are stored in the anterior pituitary.
Purple dye moves only from side B to side A
Never
Once a group of variants had a peak number of infections, did members of that same group cause another wave of infection?
No, each group of variants caused only one wave of infection.
The scientists arranged the branches into groups made up of one ancestral variant and all of its descendant, mutated variants. They are color-coded in the tree. Do all of the groups have the same number of branches or branch tips? What does this result indicate?
No; some groups experienced a higher mutation rate than others.
A(n) ________________________ inhibitor binds to a site on the enzyme that is not the active site.
Noncompetitive
__________ is the failure of __________ to separate in meiosis I or the failure of __________ to separate in meiosis II.
Nondisjunction; homologous chromosomes; sister chromatids
A _________________ mutation causes an early Stop codon to occur.
Nonsense
Nucleic acid polymers are made up of ___________________monomers
Nucleotide
is the final electron acceptor of the electron transport chain.
O2 (molecular oxygen)
There is no net movement of purple dye
Only at equilibrium
Concentration gradients exist that drive diffusion of both dyes
Only before equilibrium is reached
There is a net movement of orange dye from side A to side B
Only before equilibrium is reached
When a virus infects an E. coli cell, what part of the virus enters the bacterial cytoplasm?
Only the nucleic acid
Which of the following statements correctly describes one of the differences between open and closed circulatory systems?
Open circulatory systems are less costly than closed circulatory systems in terms of energy expenditure.
Which of the following functions of plasma-cell secreted antibodies promotes phagocytosis of foreign bacteria?
Opsonization
Which of the following two organic molecules must animals obtain from their diets in order to grow and maintain their bodies?
Organic nitrogen and organic carbon
Interstitial fluid is __________.
the fluid that fills the spaces between cells of vertebrates
Which of the following is a correct description of the events of cellular respiration and the sequence of events in cellular respiration?
Oxidation of glucose to pyruvate; oxidation of pyruvate; oxidation of acetyl-coA; oxidative phosphorylation
All of the processes involved in cellular respiration produce ATP. Which of the following processes produces the most ATP?
Oxidative phosphorylation
Which of the following is acquired outside of an animal's diet?
Oxygen
Gallstone surgery sometimes requires that the gallbladder be removed. Patients are then advised to avoid ingesting large amounts of fat because __________.
the gallbladder stores large quantities of bile, which is used to emulsify fats
Gas exchange involves the transport of two respiratory gases, oxygen and carbon dioxide. Review how each gas is transported between the atmosphere and the cells of your body by completing this exercise. Drag each statement into the appropriate bin depending on whether it applies to oxygen only, carbon dioxide only, or both oxygen and carbon dioxide.
Oxygen only: -Required for cellular respiration -Net diffusion from alveoli to lung capillaries Carbon dioxide only -net diffusion from body tissues to blood -net diffusion from lung capillaries to alveoli -sometimes transported as bicarbonate -waste product of cellular respiration Both oxygen and carbondioxide: -enters alveoli during inhalation -transported by hemoglobin
In a typical pea experiment, two true-breeding plants with distinct traits of a single character are called the __________, and the offspring are called the __________, which will always be __________.
P (or parental) generation; F1 (or first filial) generation; hybrid
Which of the following statements is most likely to be true in the case of the feedback-regulated enzymatic pathway shown?
P4 binds E1 and deactivates it.
The DNA in a cell's nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell. For example, consider these two proteins: Phosphofructokinase (PFK) is an enzyme that functions in the cytoplasm during glycolysis. Insulin, a protein that regulates blood sugar levels, is secreted from specialized pancreatic cells. Assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations. For each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (Note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)
PFK - Cytoplasm only Insulin - ER --> Golgi --> Outside cell
Bacteria can transcribe and translate human genes to produce functional human proteins because __________.
the genetic code is nearly universal
As a result of the lytic cycle, _____.
the host cell's DNA is destroyed
The natural antacid that protects the intestines against stomach acid is produced by the __________.
Pancreas
Which of the following is a pair of hormones that function to regulate blood calcium in mammals?
Parathyroid hormone and calcitonin
Unless the chromosomes were stained to show band patterns, a karyotype would be least likely to show which of the following?
Part of a chromosome turned around.
Both passive and active transport are used to move molecules into and out of cells, as shown in the figure. Identify the key differences between passive and active transport, and provide an example of each. Drag the labels to their appropriate locations in the table below
Passive Transport: How molecules move relative to a concentration gradient: Down a concentration gradient Energy Requirements: Does not require energy from cells Example: osmosis Active Transport: How molecules move relative to a concentration gradient: Against a concentration gradient Energy requirements: Require energy from cells Example: Sodium-potassium pump
A family tree that describes traits in families is called a __________.
Pedigree analysis
Which of the following is an example of positive feedback in the lumen of the stomach?
Pepsin digests molecules of pepsinogen, producing more pepsin.
The mammalian trachea and esophagus both connect to the __________.
Pharynx
What functional group is commonly used in cells to transfer energy from one organic molecule to another?
Phosphate
Which disorder is correctly matched with its cause?
Pituitary dwarfism; hyposecretion of growth hormone
Gigantism, a condition characterized by exceptionally rapid growth, is sometimes caused by a tumor that induces the gland in which it develops to overproduce a certain hormone. Where would such a tumor be expected to grow?
Pituitary gland.
Which of the following pairs correctly matches the blood component with one of its functions?
Plasma proteins; osmotic balance
Patients with leukemia, a type of cancer that affects the blood, often exhibit suppressed immunity and problems with blood clotting. Based on these two symptoms, which components of the blood are affected by this type of cancer?
Platelets and leukocytes
Which of the following events occurs first when a wound that breaks the skin has occurred?
Platelets release proteins that form clots and decrease bleeding.
A carbohydrate that yields many monosaccharides when hydrolyzed is a ______________________ .
Polysaccharide
What would the value of ΔS be for a chemical reaction in which a molecule is broken down into smaller components?
Positive
Wild type refers to __________.
the most common phenotype thought to be found in the natural population
In an X-linked, or sex-linked, trait, it is the contribution of __________ that determines whether a son will display the trait.
the mother
Steroid hormone-receptor complexes act in _____.
the nucleus
In people with sickle-cell disease, red blood cells break down, clump, and clog the blood vessels. The blood vessels and the broken cells accumulate in the spleen. Among other things this leads to physical weakness, heart failure, joint pain, and brain damage. Such a suite of symptoms can be explained by __________.
the pleiotropic effects of the sickle-cell allele
Chemical energy is a form of _____ energy.
Potential
Which of the following is/are an adaptation to an herbivorous diet?
Premolars and molars with broad, ridged surfaces
What role do major histocompatibility complex (MHC) molecules play in immunity?
Presenting antigens to T cells
__________________________ structure is the sequence of amino acids in a protein.
Primary
How do prions propagate and replicate themselves?
Prions convert normal proteins into the misfolded prion version.
How do prions, which are misfolded proteins, infect organisms? See Concept 19.3 (Page)
Prions enter brain cells and cause normal forms of the protein to refold into the prion form.
The zipper-like complex that forms in meiosis occurs during __________ and is called the __________.
Prophase I; synaptonemal complex
Mitosis unfolds through a sequence of stages marked by specific events in the cell. The structural changes in the cell are brought about by a series of tightly coordinated underlying mechanisms. Sort each process into the appropriate bin to indicate the stage of mitosis in which it occurs. If a process occurs in more than one stage, sort it to the stage when it first occurs.
Prophase- Cohesions join sister chromatids of duplicated chromosome. Tubulins assemble into spindle microtubules. Prometaphase Microtubules attach to kinetochores. Metaphase Kinetochores are motionless in relation to poles of cell. Anaphase Cohesions break down . Kinetochores move toward poles of cell. Telophase Spindle microtubules disassemble
Which of the following functions as a local regulator?
Prostaglandin
Choose the correct statement from the list below.
Proteins that are consumed in the diet are absorbed as individual amino acids following digestion.
In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs?
Pyruvate is oxidized and decarboxylated, and the removed electrons are used to reduce an NAD+ to an NADH.
Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions?
Pyruvate, ATP, and NADH
is a nonprotein organic electron carrier within the electron transport chain.
Q (ubiquinone)
________________________ structure is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.
Quaternary
Genetic information of eukaryotic cells is transferred from the nucleus to the cytoplasm in the form of __________.
RNA
Which of these is NOT a lipid? RNA phospholipid wax steroids cholesterol
RNA
Reverse transcription, carried out by retroviruses, is the process by which __________.
RNA information is copied into DNA
Which of the following catalyzes the linkage between ribonucleotides to form RNA during gene expression?
RNA polymerase
Which of the following components is required for DNA replication?
RNA primer
When comparing DNA and RNA viruses, which mutate more quickly, and why?
RNA viruses, because no proofreading is done on RNA molecules
A wild-type tomato plant (Plant 1) is homozygous dominant for three traits: solid leaves (MM), normal height (DD), and smooth skin (PP). Another tomato plant (Plant 2) is homozygous recessive for the same three traits: mottled leaves (mm), dwarf height (dd), and peach skin (pp). In a cross between these two plants (MMDDPP x mmddpp), all offspring in the F1 generation are wild type and heterozygous for all three traits (MmDdPp).
Ratio 1 : 1 : 1 : 1 : 1 : 1 : 1 :
The two main functions of the large intestine are _________.
Reabsorb water and eliminate undigested materials
Antibodies belong to which class of proteins?
Receptor
Most of the electrons removed from glucose by cellular respiration are used for which of the following processes?
Reducing NAD+ to NADH in glycolysis and the citric acid cycle AND producing a proton gradient for ATP synthesis in the mitochondria.
Look at the graph of reaction rate versus substrate concentration for an enzyme. In which region does the reaction rate remain constant?
Region C
Refer again to the graph. In which region is the enzyme saturated with substrate?
Region C
Checkpoints in the cell cycle control system __________.
Regulate the cell cycle through a variety of stop and go signals
Which term describes a steady state in which the internal conditions of an organism are kept within a narrow range without regard to the external conditions?
Regulatory homeostasis.
Addition of a nucleotide onto a DNA strand is an endergonic reaction. What provides the energy to drive the reaction?
Release of pyrophosphate from the incoming nucleotide, and then hydrolysis of the pyrophosphate to inorganic phosphate
In general, the hydrolysis of ATP drives cellular work by
Releasing free energy that can be coupled to other reactions
Variations in the reactive properties of different organic molecules are most closely associated with _____.
the presence or absence of functional groups
Viruses can vary with respect to all of the following characteristics except __________
the presence or absence of metabolic machinery
The idea behind vaccination is to induce __________ without requiring the vaccinated individual to get sick.
the primary immune response
When the protein gramicidin is integrated into a membrane, an H+ channel forms and the membrane becomes very permeable to protons (H+ ions). If gramicidin is added to an actively respiring muscle cell, how would it affect the rates of electron transport, proton pumping, and ATP synthesis in oxidative phosphorylation? (Assume that gramicidin does not affect the production of NADH and FADH2 during the early stages of cellular respiration.) Sort the labels into the correct bin according to the effect that gramicidin would have on each process.
Remains the same: -Proton pumping rate -Electron transport rate -Rate of oxygen uptake Decreases (or goes to zero) -Rate of ATP synthesis -Size of the proton gradient Increases -Nothing
What is the correct path of blood flow through vessels supplying a nephron?
Renal artery, afferent arteriole, glomerulus, efferent arteriole, peritubular capillaries and vasa recta, renal vein
All of the following statements are correct regarding respiratory surfaces except which one?
Respiratory surfaces must be dry.
How are retroviruses different from other types of viruses?
Retroviruses use the enzyme reverse transcriptase to transcribe a copy of DNA from their own RNA.
If you wanted to show the 3-dimensional shape of a protein, including the backbone structure, folds, and coils, you should use a _____________________________
Ribbon Model
Which chambers of the heart respectively receive and pump oxygen-poor blood?
Right atrium and right ventricle
If resistance increases in the capillary beds of the lung, which structure would be affected first?
Right ventricle
Gene expression is __________.
the process by which DNA directs the synthesis of proteins
Which structure is not part of the alimentary canal?
Salivary glands
This figure is an example of a(n) _____.
Saturated fat
In this reaction _____. AC is a reactant entropy has decreased the products have less potential energy than the reactants CD is a product the products have been rearranged to form reactants
the products have less potential energy than the reactants
Most cells are microscopic because at this small size, __________.
the ratio of surface area to cell volume is maximized
________________________ structure describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain.
Secondary
Besides the fact that pea plants have a short generation time, the key to Mendel's successful plant-breeding experiments was that pea plants usually __________.
Self-pollinate
Which component of a homeostatic system perceives changes in some parameter of the environment?
Sensor
Which of the following events does not occur during interphase of the cell cycle?
Separation of the sister chromatids
With a microscope, you examine some somatic cells from a woman and notice that each nucleus has two Barr bodies. What can you infer about the sex chromosomes in this individual?
She is XXX.
Which of the following actions acts to warm a homeothermic body?
Shivering.
Which of the following mammals would you expect to have the highest basal metabolic rate (BMR)?
Shrew
A ________________ mutation does not change the wild-type amino acid sequence.
Silent
If you wanted to show a generalized protein in which the focus is on the protein's function rather than its structure, you should use a _____________________________
Simple shape
Which of the following statements correctly describes the differences between simple squamous cells and stratified squamous cells?
Simple squamous cells form a single layer, which is useful for gas exchange, and stratified squamous cells are multilayered and regenerate rapidly
Carbohydrate polymers are made up of _________________ monomers.
Simple sugars
If you wanted to show the general shape of a protein, along with some important functional details such as folds and coils, you should use a ____________________________
Simplified diagram
DNA replication produces two identical DNA molecules, called ___________________________, which separate during mitosis.
Sister chromatid(s)
_______________ muscle is attached to bones.
Skeletal
Which of the following statements is incorrect regarding muscle tissue?
Skeletal muscle consists of cells that each have a single nucleus.
Which of the following human digestive system components is correctly matched with the nutrient that is chemically digested there?
Small intestine; fats
Vaccination led to the eradication of the disease ________.
Smallpox
The information in DNA is contained in __________.
the sequence of nucleotides along the length of the two strands of the DNA molecule
What type of muscle is responsible for contractions of the digestive tract and arteries?
Smooth muscle
In humans, the first line of defense against infection is __________.
the skin and mucous membranes
If you wanted to show the 3-dimensional shape of a protein, including all of the atoms composing it, you should use a ______________________________
Space-filling model
Various types of chemical bonds or interactions maintain the three-dimensional (3D) structure of large biological molecules like DNA. Not all types of bonds or interactions are shown in all diagrams. The types of bonds or interactions shown depend on the emphasis of the particular diagram. Which of the following diagrams most clearly shows the overall 3D shape and atomic composition of DNA?
Space-filling model
An enzyme is considered ______________ because of its ability to recognize the shape of a particular molecule.
Specific
Which animal would most likely be an osmoconformer?
Starfish (sea star)
Which type of organism would have the least chance of long-term survival in the given environment?
Stenohaline animals that move between fresh water and seawater
A signaling molecule is released from the adrenal gland and, after being transported through the blood, enters a cell, where it binds to a receptor and then moves into the nucleus, where it alters gene expression. What type of signaling molecule would this most likely be?
Steroid
Which of the following diagrams most clearly shows the details of the bonds between nitrogenous bases of complementary nucleotide pairs?
Structural diagram
Enzyme inhibitors disrupt normal interactions between an enzyme and its ________________.
Substrate
In a catalyzed reaction a reactant is often called a ___________________.
Substrate
Why isn't this insect drowning on the surface of the water?
Surface tension
An autocrine signal produced by a T cell has an effect on a _____________.
T cell
One strand of a DNA molecule has the base sequence 5'-ATAGGT-3'. The complementary base sequence on the other strand of DNA will be 3'-__________-5'.
TATCCA
Which of the following phases of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope?
Telophase
Which of the following pairs of connective tissue and its function is correctly matched?
Tendons; attach muscles to bones
How many genes are present in the human genome?
Tens of thousands
__________________________ structure is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids.
Tertiary
A breakfast cereal advertises that it contains essential vitamins and minerals. In this context, the word essential means __________.
That the nutrients must be supplied in the diet and cannot be made in the body
A cell biologist examined the DNA content of a cell from a fruit fly larva during the G1 phase and determined that it had 150 units of DNA. After measuring the DNA content of the same type of cell after the G2 phase, it was discovered that the cell had 300 units of DNA. How is this possible?
The DNA was replicated during the S phase of interphase, which occurs between the two G phases.
Imagine that you are walking to class and a person on a bicycle comes very close to hitting you. Your heart begins to beat faster. Which of the following structures is responsible for this reaction?
The SA node
Which of these statements about enzyme inhibitors is true?
The action of inhibitors may be reversible or irreversible.
Which of the following is changed by the presence of an enzyme in a reaction?
The activation energy
Which of the following statements about the active site of an enzyme is correct?
The active site may resemble a groove or pocket in the surface of a protein into which the substrate fits.
Which of the following is an example of the second law of thermodynamics as it applies to biological reactions?
The aerobic respiration of one molecule of glucose produces six molecules each of carbon dioxide and water.
Which event occurs first during atrial and ventricular diastole?
The atria and ventricles are relaxed, and blood flows into the atria.
Which choice below is a basic difference between Mendel's particulate hypothesis and the hypothesis of blending inheritance?
The blending inheritance hypothesis, but not the particulate hypothesis, maintained that after a mating, the genetic material provided by each of the two parents is mixed in the offspring, losing its individual identity.
Which of the following statements describes a cell that undergoes mitosis but not cytokinesis?
The cell contains more than one nucleus
Cytokinesis in animal cells is accomplished by constriction of the cell along the plane of cell division (formation of a cleavage furrow). In plant cells, which have cell walls, a completely different mechanism of cytokinesis has evolved. Which of the following statements are true of cytokinesis in plant cells? Select the two that apply.
The cell plate consists of the plasma membrane and cell wall that will eventually separate the two daughter cells. Vesicles from the Golgi apparatus move along microtubules, coalesce at the plane of cell division, and form a cell plate.
You just received a freshwater aquarium as a gift and decide to add more fish. When you get to the pet store, you find that the most beautiful fish are saltwater animals, but you decide to buy them anyway. What will happen when you put your expensive saltwater fish in your freshwater aquarium? See Concept 44.1 (Page)
The cells of the fish will take up too much water, and the fish will die.
Which of the following events occurs during metaphase of mitosis?
The chromosomes align along the metaphase plate of the cell.
Most of the NADH that delivers electrons to the electron transport chain comes from which of the following processes?
The citric acid cycle
Which part of the catabolism of glucose by cellular respiration requires molecular oxygen (O2) and produces CO2?
The combination of the citric acid cycle and electron transport
Which of the following metabolic pathways produce(s) the most ATP, per glucose molecule metabolized, during cellular respiration?
The electron transport chain and oxidative phosphorylation
Which of the following statements is correct regarding ATP?
The energy in an ATP molecule is released through hydrolysis of one of the phosphate groups.
Which of the following statements about the combustion of glucose with oxygen to form water and carbon dioxide (C6H12O6 + 6 O2 → 6 CO2 + 6 H2O) is correct? See Concept 8.2 (Page)
The entropy of the products is greater than the entropy of the reactants.
At low pH, a particular enzyme catalyzes a reaction at a high rate. At neutral pH, the enzyme is completely inactive. What statement best explains the difference in how pH affects the function of this enzyme?
The enzyme is adapted for low pH but is denatured at neutral pH, leaving it nonfunctional.
You have added an irreversible inhibitor to a sample of enzyme and substrate. At this point, the reaction has stopped completely. What can you do to regain the activity of the enzyme?
The enzyme is inactive at this point. New enzyme must be added to regain enzyme activity.
If the pores in the selectively permeable membrane became larger, but still not large enough to let the sugar pass through, what would happen during osmosis in the U-shaped tube compared to what is shown in the figure?
The final water levels would be the same as shown in the figure, but the solutions would reach near equal concentrations faster.
The ATP synthase in a human cell obtains energy for synthesizing ATP directly from which of the following processes?
The flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme
You continue your analysis by crossing the forked and twist lines. Your results are as follows: Which of the following statements best explains the outcome of this cross?
The forked mutation and the twist mutation are codominant alleles of the same locus.
What best characterizes the role of ATP in cellular metabolism?
The free energy released by ATP hydrolysis that may be coupled to an endergonic process via the formation of a phosphorylated intermediate.
Which of the following events occurs during the lytic life cycle of phages?
The host cell usually dies, releasing many new copies of the virus.
How is the production of hormones such as thyroxine and estrogen regulated?
The hypothalamus directs the anterior pituitary to produce hormones that then stimulate or inhibit the production of these hormones.
How does the hypothalamus control the secretion of growth hormone (GH) from the anterior pituitary?
The hypothalamus produces a releasing hormone that stimulates the pituitary to secrete GH.
Metabolic rate is _____. See Concept 40.4 (Page)
the total amount of energy an animal uses in a unit of time
Why is the development and distribution of a new flu vaccine required every year?
The influenza virus undergoes frequent mutations and evolves rapidly.
Mendel's law of segregation states that __________.
the two alleles for a heritable character segregate (separate from each other) during gamete formation and end up in different gametes
Why do the circulatory systems of land vertebrates have separate circuits to the lungs and to the rest of the body?
The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body.
What kind of protection does the Genetic Information Nondiscrimination Act of 2008 provide the public with regard to the use of genetic information?
The law prohibits the use of genetic test information to deny insurance coverage or employment to individuals.
Which is an accurate statement about the anatomy of the human excretory system?
The loop of Henle is located between the proximal tubule and the distal tubule.
In a series of immune system experiments, the thymus glands were removed from baby mice. Which of the following would you predict as a likely result?
The mice readily accepted tissue transplants.
Which of the following events does not occur during prophase of mitosis?
The mitotic spindle breaks down
How does the process of mitosis differ between most eukaryotes and other eukaryotes such as diatoms and dinoflagellates?
The nuclear envelope fragments in most eukaryotes but remains intact in diatoms and dinoflagellates.
Which of the following events occurs during prometaphase of mitosis?
The nuclear envelope fragments.
During binary fission in a bacterium __________.
The origins of replication move apart
A researcher added a mixture of animal proteins to a physiological buffer solution (pH 7.4) in a test tube incubated at 37°C. The researcher then added purified pepsin to the mixture, but even after several hours, the proteins were not digested. Which of the following would explain this result?
The pH was too high.
Which statement about oxygen in fish gills is correct?
The partial pressure of oxygen in blood increases as it flows through gill capillaries.
What is a locus?
The precise location of a gene on a chromosome.
The primary reason steroid hormones usually act slowly is that _____.
The primary reason steroid hormones usually act slowly is that _____.
The energy from the electrons in NADH and FADH2 fuel what process in the electron transport chain?
The pumping of H+ across the cristae of the mitochondrion
Pea plants are tall if they have the genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant. Which outcome below would indicate that the tall parent plant was heterozygous?
The ratio of tall offspring to short offspring is 1:1.
What is energy coupling?
the use of energy released from an exergonic reaction to drive an endergonic reaction
Based on graph (a), one observer suggests that a group of 100 ground squirrels would consume the same amount of oxygen per hour as 1 dog because 100 ground squirrels have the same total body mass as 1 dog. A second observer disagrees. Who is correct?
The second observer is correct; 100 ground squirrels will consume more oxygen per hour than 1 dog.
Which of the following statements is an accurate description of sex hormones?
The sex hormones have effects on tissues other than those comprising the reproductive system.
Which of the following events occurs during anaphase of mitosis?
The sister chromatids are pulled apart toward opposite sides of the cell.
How does the pH of the solution on the right compare with that of the solution on the left?
The solution on the right is basic relative to the solution on the left.
Pressure is greatest in the ventricles when __________.
the ventricles contract
HIV, the virus that causes AIDS, only infects certain cells within the immune system. This is because __________.
the virus binds to specific receptors that are only present on certain immune cells
What is the first thing that happens when body temperature increases above normal body temperature?
The thermostat in the hypothalamus activates cooling mechanisms
Which of the following best describes the arrangement of genetic information in a DNA molecule?
The three-nucleotide words of a gene are arranged in a nonoverlapping series on the DNA template strand.
Suppose that the triplet of nucleotides indicated in bold (AGC) spans two codons, that is, CTA and GCC. If the triplet AGC were deleted from this DNA coding sequence, what effect would it have on the resulting protein? 5'-ATGCTAGCCTATCGTAAC-3'
The two flanking codons would be altered, but the rest of the amino acid sequence would be the same because there would be no frameshift.
Which event of the cardiac cycle occurs when systolic blood pressure is measured?
The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria.
A plant that has been raised in a sterile environment shows symptoms of a viral infection. How would you explain this? See Concept 19.3 (Page)
The viral infection was acquired by vertical transmission.
Which of the following statements correctly describes some of the differences between arteries and veins?
The walls of arteries are much thicker and stronger than the walls of veins.
If more sugar were added to the solution on the left side of the tube, what would happen to the water level on the right side of the tube?
The water level would go down
Consider the data from both the phylogenetic tree and the graph. Groups 9, 10, and 11 all had H1N1 variants that caused a large number of infections at the same time in Taiwan. Does this mean that the scientists' hypothesis, that new variants cause new waves of infection, was incorrect? Explain your answer.
Their hypothesis was still supported; these three groups arose along different lineages but emerged to cause illness during the same wave.
The partial pressure of oxygen at a particular point in the bloodstream is 100 mm Hg. Under what circumstance will there be a net diffusion of oxygen from the water into the bloodstream at this location?
There will be a net diffusion of oxygen from the water into the bloodstream only if the partial pressure of oxygen in the water is greater than 100 mm Hg.
Assume that an organism exists in which crossing over does not occur, but that all other processes associated with meiosis occur normally. Consider how the absence of crossing over would affect the outcome of meiosis. If crossing over did not occur, which of the following statements about meiosis would be true? Select all that apply.
There would be less genetic variation among gametes
Which statement describes what would most likely happen to microbes in the blood?
They are phagocytosed by macrophages in the spleen.
Which of the following best describes cis-trans isomers?
They differ in their spatial arrangement around inflexible double bonds.
Which is a true statement about memory cells?
They have a longer lifespan than plasma cells.
Which of the following statements about homologous chromosomes is correct?
They have genes for the same traits at the same loci.
Why do some species employ both mitosis and meiosis, whereas other species use only mitosis? See Concept 13.2 (Page)
They need both if they are producing plant gametes.
Which of the following statements best describes the role of mast cells in the inflammatory response?
They release chemicals that dilate blood vessels near the wound site, allowing blood components to enter the region from the bloodstream.
What is the function of endocrine glands?
They release hormones into the bloodstream for distribution around the body.
The epithelium that lines the stomach has many deep infoldings, or pits. In what way do these pits function as glands?
They secrete gastric juice into the main chamber of the stomach.
Where in the body would you be most likely to find secretory cells shaped like dice?
Thyroid and salivary glands
Suppose that a woman had to have part of her thyroid gland surgically removed. She would most likely suffer from a condition known as hypothyroidism due to too little thyroid function. Predict how this woman's hypothyroidism would affect prolactin levels in her body. Which choice describes how surgical hypothyroidism would likely affect prolactin levels?
Thyroid hormones levels decrease, TRH levels increase, and PRL levels increase.
The volume of air inhaled and exhaled with each breath is called _______.
Tidal volume
Duchenne muscular dystrophy is caused by a sex-linked recessive allele. Its victims are almost invariably boys, who usually die before the age of 20. Why is this disorder almost never seen in girls?
To express an X-linked recessive allele, a female must have two copies of the allele.
In mitochondrial electron transport, what is the direct role of O2O2?
To function as the final electron acceptor in the electron transport chain
Place the blue labels in their proper locations on this diagram showing the process of transcription. Then, use the pink labels to identify the corresponding RNA nucleotide that belongs in each pink target. Pink labels can be used once, more than once, or not at all.Drag the appropriate labels to their respective targets.
Top (Purple/Blue boxes): Nontemplate Strand ; RNA polymerase Middle (Purple/Blue boxes): Template Strand Middle (Pink boxes): A U G C Last (Purple/Blue boxes): RNA being produced
__________ is the synthesis of RNA using information in the DNA.
Transcription
RNA plays important roles in many cellular processes, particularly those associated with protein synthesis: transcription, RNA processing, and translation. Drag the labels to the appropriate bins to identify the step in protein synthesis where each type of RNA first plays a role. If an RNA does not play a role in protein synthesis, drag it to the "not used in protein synthesis" bin.
Transcription/ RNA Processing: snRNA mRNA pre-mRNA Translation: tRNA rRNA Not used in protein synthesis: RNA primers
A small amount of ATP is made in glycolysis by which of the following processes?
Transfer of a phosphate group from a fragment of glucose to ADP by substrate-level phosphorylation
Beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____. transferring of information from DNA to messenger RNA removal of introns from RNA and the stitching together of exons linking of nucleotides to form a polypeptide translation of an RNA nucleotide sequence into a sequence of amino acids translation of a DNA nucleotide sequence into a sequence of amino acids
Transferring of information from DNA to messenger RNA
__________ is the synthesis of a polypeptide using information in the mRNA.
Translation
Which of the following is a function of the circulatory system?
Transporting nutrients
(T/F) As a result of crossing over, sister chromatids are no longer identical to each other.
True
(T/F) Crossing over occurs at the ends of chromosomes, rather than near the centromeres
True
(T/F) For crossing over to occur, homologous chromosomes must align precisely early in prophase I so that nonsister chromatids can exchange corresponding segments of DNA.
True
(True of False) Reabsorption of water and solutes in the proximal tubule reduces the volume of the filtrate.
True
(True or False) The collecting duct becomes more permeable to water when the kidneys are in water-conservation mode.
True
Complementary base pairing relies on the number of hydrogen bonds that each base can make. (T/F)
True
In a single nucleotide, the phosphate group is attached to the 5' carbon of the sugar unit. (T/F)
True
The phosphate attached to the 5' carbon of a given nucleotide links to the 3' -OH of the adjacent nucleotide (T/F)
True
The site of inflammation may become swollen due to the increased numbers of cells and fluids at the site and painful due to signals from pain receptors.
True
True or false? Organisms must maintain homeostasis because optimal enzyme activity is achieved within a very narrow range of conditions.
True
True or false? The homeostatic system for blood calcium concentration is maintained by the hormones calcitonin and parathyroid hormone.
True
True or false? The pancreas is responsible for producing hormones that maintain the homeostatic levels of glucose in the blood.
True
From these results, determine the relationship between the mutant allele and its corresponding wild-type allele in each line.
Twist: The mutant allele is dominant to its corresponding wild type allele Forked: The mutant allele is dominant to its corresponding wild type allele Pale: The mutant allele is neither dominant nor completely recessive to its corresponding wild type allele
What is the total production of ATP, NADH, and FADH2 in the citric acid cycle from one molecule of glucose?
Two ATP, six NADH, and two FADH2
Which of the following events occurs during telophase of mitosis?
Two distinct daughter nuclei form in the cell.
When RNA is being made, the RNA base _________ always pairs with the base __________ in DNA.
U; A
Suppose that a portion of double-stranded DNA in the middle of a large gene is being transcribed by an RNA polymerase. As the polymerase moves through the sequence of six bases shown in the diagram below, what is the corresponding sequence of bases in the RNA that is produced? Enter the sequence of bases as capital letters with no spaces and no punctuation. Begin with the first base added to the growing RNA strand, and end with the last base added.
UGAGCC
Use the codon table to determine which mRNA triplets code for the amino acid cysteine, Cys. Select all that apply
UGU UGC
You perform a testcross using F1 dihybrid flies. If, in the resulting offspring, the percentages of parental and recombinant offspring are about the same, this would indicate that the two genes are __________.
Unlinked
Which of the following is a tube that carries urine from the kidneys to the urinary bladder in a mammal?
Ureter
Can you match these prefixes, suffixes, and word roots with their definitions? heat:
therm-
The functional relationship between the anterior pituitary and the posterior pituitary is that ___________.
they both release hormones in response to signals from the hypothalamus
Which of the following statements about blood circulation in the body is true?
Valves prevent the backflow of blood into the atria and ventricles.
Which of the following correctly lists the sequence of blood flow in mammals?
Venae cavae, right atrium, right ventricle, pulmonary arteries, lungs, pulmonary veins, left atrium, left ventricle, aorta
The lungs consist of many small air sacs and blood vessels, which greatly increase surface area and improve the transfer of substances through their walls. The structures in the digestive system most similar in function to these air sacs and capillaries are the __________.
Villi and microvilli
Which of the following statements correctly describes one difference between virulent phages and temperate phages?
Virulent phages replicate through the lytic cycle only, and temperate phages replicate using both the lytic and the lysogenic cycles.
Why are viruses often considered to be nonliving?
Viruses do not carry out metabolic processes, a primary characteristic of living organisms.
Sort the items according to whether they may be found only in free virus particles, only in uninfected host cells, or in both viruses and host cells. Drag each item to the appropriate bin.
Viruses only- Capsid, Capsomere (core protein), Envelope with glycoproteins Host cell only- Ribosome Both- Protein, RNA, DNA
How does a virus differ from a bacterium? Select all that apply.
Viruses, unlike bacteria, lack metabolic enzymes.
___________________ is absorbed from some foods like carrots in the form of carotene. The vitamin accumulates in the rods and cones of the eyes and plays a role in vision.
Vitamin A
___________________ is involved in the formation of hydroxyproline and hydroxylysine, which are important amino acids and part of the collagen that forms the connective tissues. Lack of this vitamin causes scurvy, which can be prevented with citrus and other fruits.
Vitamin C
Vitamins are classified based on their solubility in water. Which of the following statements regarding the classification of the vitamins listed is correct?
Vitamin C is water-soluble, and vitamin A is fat-soluble.
Which of the following pairs of vitamins and their function(s) is correctly matched?
Vitamin D; absorption and use of calcium and phosphorous
Which of the following pairs of vitamins and their deficiency symptoms is correctly matched?
Vitamin E; nervous system degeneration
Which of the following is not moved out of or into the filtrate of a nephron through active transport by epithelial cells?
Water
Which of the following is reabsorbed in the proximal tubule, leading to a reduction in the overall filtrate volume? Select all that apply
Water and solutes
Sort the vitamins according to whether they are water-soluble or fat-soluble. Sort the items into the appropriate bin.
Water soluble - Vitamin B1, Vitamin C Fat soluble - Vitamin D, Vitamin K, Vitamin A
Who is credited with explaining the structure of the DNA double helix?
Watson and Crick
Which of the following organisms would produce antibodies as part of an immune response?
Whale
The "triplet code" refers to the fact that ___________
three nucleotides code for a single amino acid
When __________ form after an exposure to ultraviolet (UV) light, a __________ can remove the damaged nucleotides and replace them with normal nucleotides.
thymidine dimers; nucleotide excision repair enzyme
Which of these nitrogenous bases is found in DNA but not in RNA?
thymine
In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.
thymine ... cytosine
Chargaff analyzed DNA and found that the numbers of adenine molecules is approximately equal to the numbers of __________ molecules and that the numbers of __________ molecules is approximately equal to the numbers of __________ molecules.
thymine; guanine; cytosine
Hyperthyroidism, typically characterized by a high metabolic rate and high blood pressure, might be expected when __________.
thyroid-stimulating hormone (TSH) concentration is high
Which of these cell junctions form a barrier to the passage of materials?
tight junctions
In incomplete dominance, the offspring __________.
Will have an appearance that's intermediate between those of the two parental types
If you wanted to show the 3-dimensional shape of a protein by showing the amino acid side chains and their interactions, you should use a ________________________________
Wireframe model
Color in squash is controlled by epistatic interactions in which color is recessive to no color. At the first locus white squash (W) is dominant to colored squash (w). At the second locus yellow (Y) is dominant to green (y). What is the phenotype of a squash with the genotype wwYy?
Yellow
One variant in the green groups (Groups 1, 3, and 6) was used to make a vaccine that was distributed very early in the pandemic. Based on the graphed data, does it look like the vaccine was effective? Why or why not?
Yes, it was effective; the green line never reaches 100 on the y-axis.
The main function(s) of connective tissues in the body is/are _________.
to hold tissues and organs in place and to join adjacent tissues together
Nervous tissue functions _____.
to sense stimuli
The unwinding of DNA at the replication fork causes twisting and strain in the DNA ahead of the fork, which is relieved by an enzyme called __________.
topoisomerase
A physiological state of decreased activity and metabolism that is an adaptation enabling animals to save energy while avoiding difficult and dangerous conditions is known as _________.
torpor
Can you match these prefixes, suffixes, and word roots with their definitions? across:
trans-
Which of the following contributes most significantly to the kidney's high energy expenditure?
transport of NaCl in the thick segment of the ascending limb of the loop of Henle
A fat molecule with THREE fatty acids is called a triacylglycerol, or a _____________________.
triglyceride
When an individual has an additional chromosome, that chromosome set is called __________, and the condition is known as __________.
trisomic; aneuploidy
At the end of mitosis, __________ daughter cells that are genetically __________ are formed, while at the end of meiosis, __________ daughter cells that are genetically __________ are formed.
two, identical; four, distinct
X inactivation occurs when there is/are at least __________ X chromosomes present in an individual, forming a structure called a __________ by a __________ event.
two; Barr body; random
In humans, a normal male's somatic cells will have __________ set(s) of chromosomes and sex chromosomes designated as __________ and __________, while in bees and ants, a normal male's somatic cells have __________ set(s) of chromosomes, which are __________.
two; X; Y; one; haploid
Somatic cells in humans contain __________ set(s) of chromosomes and are therefore termed __________.
two; diploid
The graph presents three activation energy profiles for a chemical reaction (the hydrolysis of sucrose): an uncatalyzed reaction, and the same reaction catalyzed by two different enzymes. Rank these by reaction rate, as measured by the rate of product formation per unit time, from lowest reaction rate to highest reaction rate. To rank items as equivalent, overlap them.
uncatalyzed reaction -----> reaction catalyzed by enzyme A ---------> reaction catalyzed by enzyme B
In our bodies, the primary nitrogen-containing compound excreted by our kidneys is __________.
urea
The osmolarity gradient is also maintained by the passive transport of ___________________
urea
The most effective molecule for nitrogenous waste disposal in desert animals would be __________.
uric acid because it does not require water for excretion
What is the most effective way to stop viral infections? See Concept 19.3 (Page)
vaccines
The bonds or interactions between stacked nucleotide units that help hold the DNA molecule together are
van der Waals interactions
All of the following increase blood pressure except _______.
vasodilation
Among humans, increased interest in food intake normally occurs _____. See Concept 41.5 (Page)
via chemical signals released when the stomach is empty
In the lysogenic cycle _____.
viral DNA is replicated along with host DNA
The pointer is indicating the _____.
viral protein coat
Circular RNA molecules that function like a virus in plants are termed __________.
viroids
The ________________________ act as coenzymes in the body. They do not stay bonded to only one enzyme, but are used over and over again by different enzymes.
water-soluble vitamins
Which of the following sequences shows a frameshift mutation compared to the wild-type mRNA sequence?
wild-type: 5'-AUGCAUACAUUGGAGUGA-3' mutant: 5'-AUGCAUACAUCUGGAGUGA-3'
If the two traits that Mendel looked at in his dihybrid cross of smooth yellow peas with wrinkled green peas had been controlled by genes that were located near each other on the same chromosome, then the F2 generation __________.
would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment
In Labrador retrievers, a dog that has the genotype BBee, where BB produces black-pigmented fur and ee produces yellow-pigmented fur, would have __________ fur and would exhibit __________.
yellow; epistasis
Animals can be classified according to their mode of thermoregulation. Sort the animals below, indicating their likely thermoregulatory strategy. Note that poikilotherms are sometimes referred to as heterotherms. Drag each animal to the appropriate bin.
•homeothermic endotherm: walrus, eagle, coyote• homeothermic ectotherm: arctic shrimp• poikilothermic ectotherm: salamander, freshwater catfish, butterfly
Stroke occurs when _____. See Concept 42.4 (Page)
a blood clot enters the cerebral circulation, blocking an artery and causing the death of brain tissue
All known birds and mammals have ________.
a double circulatory system and a four-chambered heart
Huntington's disease is an example of a genetic disorder caused by __________.
a lethal dominant allele that afflicts an individual later in life
In regard to its role in the endocrine system, nitric oxide (NO) is best described as ______________.
a local regulator
Female mammals have two X chromosomes, one from their mother and one from their father. During X inactivation, one X chromosome in each embryonic cell is randomly inactivated; therefore, all of the tissues that arise from that cell have the same inactivated X chromosome. Female mammals are therefore considered to be __________ of the maternal and paternal cells.
a mosaic
The H1N1 2009 outbreak is considered to have been which of the following? See Concept 19.3 (Page)
a pandemic
Glycogen is ______________________________
a polysaccharide found in animals
Which of these is exhibiting kinetic energy?
a space station orbiting Earth
In this activity, you will demonstrate your understanding of antiparallel elongation at the replication forks. Keep in mind that the two strands in a double helix are oriented in opposite directions, that is, they are antiparallel. Drag the arrows onto the diagram below to indicate the direction that DNA polymerase III moves along the parental (template) DNA strands at each of the two replication forks. Arrows can be used once, more than once, or not at all.
a) ----> b) ----> c) <---- d) <----
Suppose that you perform the cross discussed in Part B: MmDdPp x mmddpp. You plant 1000 tomato seeds resulting from the cross, and get the following results: Drag the labels onto the chromosome diagram to identify the locations of and distances between the genes. Gene m has already been placed on the linkage map
a) 12cM b) 5cM c) d d) p
In the life cycle of an organism, meiosis is paired with the process of fertilization. Understanding the life cycle of an organism is the key to understanding how sexual reproduction ensures the inheritance of traits from both parents and also introduces genetic variation. Complete the diagram to show the life cycle of a typical animal. Follow these steps: Drag labels of Group 1 to identify each stage of the life cycle. Drag labels of Group 2 to identify the ploidy level at each stage. Drag labels of Group 3 to identify the process by which each stage
a) 2n b) 2n c) meiosis d) meiosis e) n f) egg g) sperm h) n i) fertilization j) 2n k) zygote l) mitosis m) 2n n) meiosis o) n p) egg
You continue your genetic analysis by crossing the forked and pale mutant lines with each other. The leaves of the F1 are light green (intermediate between pale and wild-type leaves) and forked. The F2 has six phenotypic classes, as shown below. You designate the forked mutant allele as F (wild type = f+ ) and the pale mutant allele as p (wild type = P). 1. Consider the alleles for leaf color first. Drag the labels to the targets in Group 1 to identify the genotype of each F2 class. Remember that p (the pale mutant allele) and P (the wild-type allele) are incompletely dominant to each other. 2. Consider the alleles for leaf shape next. Drag the labels to the targets in Group 2 to identify the genotype of each F2 class. Remember that F (the forked mutant allele) is dominant to f + (the wild-type allele).
a) PP b) F_ c) Pp d) F_ e) pp f) F_ g)PP h)f+f+ i)Pp j)f+f+ k)pp l)f+f+
Meiosis ensures the transmission of traits from one generation to the next. At the same time, it is a key process that introduces genetic variation into the traits that offspring inherit from their parents. In this tutorial, you will explore the genetic context of meiosis. Drag the labels from the left to their correct locations in the concept map on the right. Part A - Mitosis terminology
a) chromatin b) genes c) chromosomes d) genome e) traits f) locus g) gametes
This diagram shows a diploid nucleus (2n=8) in which chromosome replication has occurred in preparation for mitosis (top) and meiosis (bottom). The nucleus at top right is now in prophase of mitosis; the nucleus at bottom right is now in prophase I of meiosis. Drag the labels to their appropriate targets to correctly identify the various chromosome structures. Labels can be used more than once.
a) non-homologous chromosomes b) sister chromatids c) homologous chromosomes d) centromere e) non-sister chromatids f) homologous chromosomes g)sister chromatids
In one of Morgan's experiments, he crossed his newly discovered white-eyed male with a red-eyed female. (Note that all of the females at that time were homozygous for red eyes because the allele for white eyes had not yet propagated through Morgan's flies.) All of the F1 flies produced by this cross (both males and females) had red eyes. Next, Morgan crossed the red-eyed F1 males with the red-eyed F1 females to produce an F2 generation. The Punnett square below shows Morgan's cross of the F1 males with the F1 females.
a) w+ b) w c) w+w+ d) w+Y e)w+w f) wY
When Gregor Mendel conducted his genetic experiments with pea plants, he observed that a trait's inheritance pattern was the same regardless of whether the trait was inherited from the maternal or paternal parent. Mendel made these observations by carrying out reciprocal crosses: For example, he first crossed a female plant homozygous for yellow seeds with a male plant homozygous for green seeds, and then crossed a female plant homozygous for green seeds with a male plant homozygous for yellow seeds. Unlike Mendel, however, Morgan obtained very different results when he carried out reciprocal crosses involving eye color in his fruit flies. The diagram below shows Morgan's reciprocal cross: He first crossed a homozygous red-eyed female with a white-eyed male, and then crossed a homozygous white-eyed female with a red-eyed male. Drag the labels to their appropriate locations to complete the Punnett squares for Morgan's reciprocal cross.
a) wY b) Y c) w+ d) w+Y e) w+Y f) Y g) w h) wY
B cells are involved in the humoral immune response. The flowchart below summarizes the steps involved in B cell activation. Drag the labels to their appropriate locations on the flowchart below. (Note that TCR stands for T cell receptor.)
a. antigen-presenting cell presnets antigen on class II MHC b. Helper T cell recognizes antigen using TCR and CD4 c. Helper T cell binds to B cell and releases cytokines d B cell presents antigen on class II MHC molecule e. B cell differentiates into plasma cells and memory cells f. Plasma cells secrete antibodies
Cytotoxic T cells are the effector cells in the cell-mediated immune response. The diagram below summarizes the interaction of a cytotoxic T cell and its target cell. Drag the labels to their appropriate locations on the diagram below using the following steps. --Use targets of Group 2 to indicate the types of cells shown. --Then, use targets of Group 1 to the remaining targets. The labels under the cell on the left should describe what happens to that cell at each step. The labels under the cell on the right should describe what happens to that cell at each step. Note that TCR stands for T cell receptor.
a. cytotoxic T cell b. infected cell c. recognizes cell using TCR and CD8 d. presents antigen on class I MHC e. Releases perforin an granzymes f. undergoes enzyme attack g. moves on to destroy another cell h. Undergoes apoptosis
The cell cycle represents the coordinated sequence of events in the life of a cell from its formation to its division into two daughter cells. Most of the key events of the cell cycle are restricted to a specific time within the cycle. In this exercise, you will identify when various events occur during the cell cycle. Recall that interphase consists of the G1, S, and G2 subphases, and that the M phase consists of mitosis and cytokinesis.
a. non-dividing cells exit cell cycle b. at this point, cell commits to go through the cycle c. DNA replicate d. Two centrosomes have formed e. mitotic spindle begins to form f. cell divides, forming two daughter cells
Thermoregulation in the body is accomplished by several feedback systems. The feedback system shown here uses vasoconstriction and vasodilation in the skin and extremities to regulate body temperature. Drag the labels to their appropriate locations on the diagram of the feedback system below. Labels can be used once, more than once, or not at all.
a. vasodilation b. body temperature decreases c. homeostasis d. body temperature increases e. vasoconstriction f. negative
Label the diagram of the kidney and nephron below. Drag the labels to their appropriate locations on the diagram below. Labels can be used once, more than once, or not at all.
a: renal cortex b: renal medulla c: ureter d: distal tubule e: proximal tubule f: Bowman's capsule g: glomerulus h: renal cortex i: renal medulla j: loop of Henle k: collecting duct
Prions are __________ that are thought to cause disease by __________.
abnormally shaped proteins; inducing similar but normally shaped proteins in the brain to adopt the abnormal form
In DNA, the two purines are __________, and the two pyrimidines are __________.
adenine and guanine; cytosine and thymine
Leptin, an appetite regulator, is produced in __________ and at high levels can lead to __________.
adipose tissue; suppressed appetite
The F1 generation differed from the F2 in Mendel's experiments in that __________.
all of the F1 showed the dominant phenotype, but only three-fourths of the F2 did
Can you match these prefixes, suffixes, and word roots with their definitions? other:
allo-
The process of stabilizing the structure of an enzyme in its active form by the binding of a molecule is an example of __________.
allosteric regulation
An open circulatory system __________.
allows interstitial fluid to mix freely with vascular fluid
The life cycle called __________ in plants has two multicellular stages: the __________ and the __________.
alternation of generations; haploid gametophyte; diploid sporophyte
Gas exchange in the lungs of mammals occurs in the __________.
alveoli
Freshwater fish excrete nitrogenous wastes as _____. See Concept 44.2 (Page)
ammonia
Double circulation circulatory systems are found in ________, and single circulation circulatory systems are found in ________.
amphibians; fish
Examples of alterations of chromosomal structures include all of the following except __________.
aneuploidy
Down syndrome is an example of __________, and the child is __________ for chromosome 21.
aneuploidy; trisomic
Extracellular pathogens such as viruses and bacteria in body fluids are attacked by _____. See Concept 43.3 (Page)
antibodies from plasma cells
What hormone promotes water retention by the kidneys?
antidiuretic hormone (ADH)
Somatic cells in animals differ from gametes in that somatic cells __________.
are all of the cells of the body except for the gametes and their precursors
Linked genes __________.
are located near each other on the same chromosome
Enantiomers are molecules that _____.
are mirror images
Your blood pressure is 120/70. The "120" indicates __________, and the "70" indicates __________.
arterial pressure during heart contraction; arterial pressure during heart relaxation
A function of cholesterol that does not harm health is its role _____.
as a component of animal cell membranes
In which section of the nephron does the filtrate have a higher osmolarity than the blood when it enters and lower osmolarity than the blood when it leaves?
ascending limb of the loop of Henle
A clone is the product of __________.
asexual reproduction and mitosis
Receptors for nonsteroid hormones are located in _____.
association with a cell's plasma membrane
Cartilage is found _____.
at the ends of bones such as the femur
The role of DNA polymerases in DNA replication is to __________.
attach free nucleotides to the new DNA strand
The pedigrees below show the inheritance of three separate, rare autosomal conditions in different families. For each pedigree, decide if the condition is better explained as recessive or dominant. Drag the correct label to the appropriate location. Labels can be used once, more than once, or not at all.
autosomal dominant reaction, autosomal dominant reaction, autosomal recessive.
A virus that infects bacteria is called a __________, which is made up of the macromolecules __________ and __________.
bacteriophage; DNA; protein
Viruses that infect bacteria are called __________.
bacteriophages
When crossing over occurs between two linked genes in an F1 dihybrid testcross, the frequency of the parental types will always __________ the frequency of the recombinant types when compared to Mendel's unlinked genes.
be greater than
All of the following processes occur in the nephron of the kidney except ________.
blood cell formation
As a young girl, Maria suffered a head injury that damaged her pituitary. An injury to the pituitary is particularly serious because of all the functions controlled by this gland. As Maria got older, she and her doctors found that all of the following except her __________ were affected.
blood sugar level
Histamine is an important signaling molecule in the immune system that directly triggers __________.
blood vessels to dilate and become more permeable
Ligaments connect ________ to ________
bone; bone
When you exhale, __________.
both the diaphragm and the rib muscles relax
Cardiac muscle is the only muscle composed of _____ fibers.
branched
Lysozyme plays a role in immunity through _________.
breaking down bacterial cell walls
Which hormone opposes the action of parathyroid hormone?
calcitonin
The nucleic acid of a virus particle is enclosed in a protein coat. What is it called? See Concept 19.1 (Page)
capsid
Which of functional groups listed below behaves as an acid?
carboxyl
Microscopic analysis of an unknown tissue sample reveals the presence of chondrocytes, indicating that the sample was probably taken from __________ tissue.
cartilage
What is the function of reverse transcriptase?
catalyzing the formation of DNA from a RNA template
A neuron receives nerve impulses from other neurons via its _________ and __________.
cell body; dendrites
Different types of food are eaten by various groups of animals, but it is usually true that _____. See Concept 41.4 (Page)
cellulose digestion in ruminant mammals occurs before the ingested foods reach the small intestine
Innate immunity and acquired immunity are both _____. See Concept 43.1 (Page)
characteristics of all vertebrate animals
The presence of fatty acids and amino acids in the chyme from the stomach triggers the small intestine to secrete a hormone known as _____.
cholecystokinin, or CCK
The __________ states that genes have specific positions on chromosomes and that chromosomes undergo both __________ and __________.
chromosomal theory of inheritance; segregation; independent assortment
These molecules are _____.
cis-trans isomers (geometric isomers)
The proliferation of the B lymphocyte to which a specific antigen binds is referred to as __________.
clonal selection
In general, B vitamins function in your body as ________.
coenzymes
Of the three alternative models of DNA replication, which are the __________ models, the one that explains how DNA replicates is the __________ model.
conservative, semiconservative, and dispersive; semiconservative
Somatic cells in humans differs from gametes in that human somatic cells __________.
contain two sets of each of the 23 chromosome types
The outer part of the kidney is the _____.
cortex
Because the bacterial cell's DNA is not surrounded by a nuclear envelope, __________ occur(s).
coupled transcription and translation
The bonds or interactions that hold together adjacent nucleotides in the sugar-phosphate backbone of DNA are
covalent bonds
Restriction enzymes help defend bacteria against viral infections by __________.
cutting viral DNA once it has entered the cell
Lizards also thermoregulate and, as in humans, thermoregulation in lizards involves negative feedback. Lizards, however, are ectotherms and gain most of their heat from external sources. Therefore, they often use behavioral mechanisms to adjust their body temperature. For example, if a lizard's body temperature drops below its normal range, the lizard may seek a sunny resting spot to warm up. What are the stimulus and the response in this example? Drag the phrases on the left to complete the sentence on the right. Not all phrases will be used. The stimulus is _____________________, and the response is ______________________
decreased body temperature, behavior to seek a sunny spot.
What is another name for a condensation reaction?
dehydration
The function of tRNA during protein synthesis is to __________.
deliver amino acids to their proper site during protein synthesis
A neuron consists of _________
dendrites, a cell body, and axons
Identify three possible components of a DNA nucleotide.
deoxyribose, phosphate group, thymine
The primary role of _____ is to bind animal cells together.
desmosomes
Our immune system does not usually attack our own healthy tissues because lymphocytes that target "self" tissue are __________.
destroyed or rendered nonfunctional
Cis-trans isomers (geometric isomers) are molecules that _____.
differ in the arrangement of their atoms about a double bond
The process of __________ breaks down food into small molecules, and during the process of __________, these molecules are taken up by an animal's cells
digestion; absorption
Regardless of whether an organism is an animal, a plant, a fungus, or an algal cell, all zygotes are __________ and are formed during the __________ of two __________ gametes.
diploid; fertilization; haploid
During interphase, the genetic material of a typical eukaryotic cell is __________.
dispersed in the nucleus as long strands of chromatin
Stop codons are unique because they __________.
do not code for amino acids that allow a releasing factor to bind to the A site of the ribosome
Observations of cancer cells in culture support the hypothesis that cancer cells __________.
do not exhibit density-dependent inhibition
Achondroplasia, a type of dwarfism, and Huntington's disease are examples of __________, with the exception that the Huntington's allele is __________.
dominant inherited disorders; lethal
Osmoregulation in a freshwater fish would not include ___________.
drinking large amounts of water
The hormone epinephrine causes opposite effects in two populations of target cells because _____. See Concept 45.1 (Page)
each set of target cells has different receptor-transduction mechanisms
The diagram below shows a replication bubble with synthesis of the leading and lagging strands on both sides of the bubble. The parental DNA is shown in dark blue, the newly synthesized DNA is light blue, and the RNA primers associated with each strand are red. The origin of replication is indicated by the black dots on the parental strands. Rank the primers in the order they were produced. If two primers were produced at the same time, overlap them.
earliest h, a b, g c,f d,e latest Pair them together
Genomic imprinting in mammals appears to primarily affect genes involved in __________.
embryonic development
The reaction ADP + P --> ATP is a(n) _____ reaction.
endergonic
This graph illustrates a(n) _____ reaction. exergonic hydrolysis endergonic catabolic spontaneous
endergonic
Which of these reactions requires a net input of energy from its surroundings?
endergonic
An organism that generates body heat by means of its own metabolism is _________, and an organism that gains body heat from external sources is ________.
endothermic; ectothermic
A widespread outbreak of a viral disease is called a(n) __________, and a global outbreak is called a(n) __________.
epidemic; pandemic
Which of these hormones are responsible for the "fight or flight" response to danger?
epinephrine and norepinephrine
Which of these is a nonsteroid hormone?
epinephrine and oxytocin
Materials that an animal cannot assemble from simpler organic molecules and that must be obtained from the diet are called __________.
essential nutrients
As filtrate passes through the long loop of Henle, salt is removed and concentrated in the interstitial fluid of the kidney medulla. Because of this high salt concentration, the nephron is able to __________.
establish a hyperosmotic interstitial medullary concentration
Which of these extracellular signal molecules could diffuse through a plasma membrane and bind to an intracellular receptor?
estrogen
The TATA box is a __________ that allows for the binding of __________ and __________.
eukaryotic promoter; transcription factors; RNA polymerase II
A(n) _____ reaction occurs spontaneously.
exergonic
The energy for an endergonic reaction comes from a(n) _____ reaction.
exergonic
The following reaction A --> B + C + heat is a(n) _____ reaction.
exergonic
Select the INCORRECT association.
exergonic ... uphill
In a marine environment, animals that are iso-osmotic relative to their environment __________.
experience no net water loss by osmosis
A juxtamedullary nephron differs from a cortical nephron in that a juxtamedullary nephron ________.
extends far into the inner medulla of the kidney
Can you match these prefixes, suffixes, and word roots with their definitions? outside of:
extra-
The __________________ are not involved as coenzymes. But they are still essential in our diet, and they are involved in important processes such as vision, bone formation, protection from oxidation, and blood clotting.
fat-soluble vitamins
In X-linked patterns of inheritance, __________.
fathers pass X-linked alleles only to their daughters, and mothers pass X-linked alleles to both their daughters and their sons
A fat molecule also includes one, two, or three ___________________ molecules.
fatty acid
The loss of water from the ____________________ results in urine that is highly concentrated.
filtrate
Choose the list that correctly ranks metabolic rates per gram of body mass, from lowest to highest. See Concept 40.4 (Page)
fish, dog, mouse
Many insects, birds, and other reptiles excrete nitrogenous wastes in the form of uric acid, which __________.
forms solids that are relatively insoluble and nontoxic
A water molecule can bond to up to _____ other water molecules by ____ bonds.
four ... hydrogen
Insertions and deletions are called __________ mutations.
frameshift
How are human mitochondria inherited? See Concept 15.5 (Page)
from the mother only
Which of the following terms associated with transcription describe regions of nucleic acid?
gene promoter terminator
Gene silencing is called __________.
genomic imprinting
The bed of capillaries in a vertebrate kidney where water, urea, and salts are filtered out of the blood is the __________.
glomerulus
Adrenocorticotropic hormone (ACTH) triggers the release of _____ in response to stress.
glucocorticoids
In the overall process of glycolysis and cellular respiration, __________ is oxidized and __________ is reduced.
glucose; oxygen
Can you match these prefixes, suffixes, and word roots with their definitions? sweet:
glyc-
A fat molecule is composed of two types of smaller molecules, including only one molecule of
glycerol.
FSH (follicle-stimulating hormone) and LH (luteinizing hormone) are tropic hormones that are also known as __________.
gonadotropins
Polysomes may be defined as __________.
groups of ribosomes
Vaccines for viral diseases are __________ and help prevent infection by __________.
harmless derivatives of pathogenic viruses; stimulating the immune system to mount a defense against the actual pathogen
To make a buffer, you need to ...
have a weak acid or a weak base half ionized in water.
In this reaction.... entropy has decreased heat has been released to the environment the chemical energy of the products is greater than that of the reactants the kinetic energy of the reactants is less than that of the products disorder has decreased
heat has been released into the environment
Which of these are by-products of cellular respiration?
heat, carbon dioxide, and water
As DNA replication continues and the replication bubble expands, the parental double helix is unwound and separated into its two component strands. This unwinding and separating of the DNA requires three different types of proteins: helicase, topoisomerase, and single-strand binding proteins. Sort the phrases into the appropriate bins depending on which protein they describe.
helicase: binds at the replication fork breaks H-bonds between bases topoisomerase: breaks covalent bonds in DNA backbone binds ahead of the replication fork single-strand binding protein: binds after the replication fork prevents H-bonds between bases
When an electron loses a discrete amount of energy, it moves from a __________ electron shell to a __________electron shell, which is _________________ the nucleus. lower/ higher lower/ higher farther from/ closer to
higher, lower, closer to
The way this heating system maintains a stable room temperature is similar to the way an animal's body controls many aspects of its internal environment. The maintenance of a relatively constant internal environment is known as ___________________.
homeostasis
What can we observe in order to visualize Mendel's Law of Segregation? See Concept 15.1 (Page)
homologous chromosomes separating during meiosis I
What is the source of a viral envelope?
host cell membrane
A fatty acid includes a carboxyl group (-COOH) at one end as well as a long ____________________
hydrocarbon chain
What name is given to the bond between water molecules?
hydrogen
The bonds or interactions that hold together complementary bases from opposite strands of DNA are
hydrogen bonds
The bonds that hold tRNA molecules in the correct three-dimensional shape are __________.
hydrogen bonds
The two sugar-phosphate strands that form the rungs of a DNA double helix are joined to each other through __________.
hydrogen bonds between nucleotide bases
What is the name of the process during which a bond between two monomers is broken?
hydrolysis
What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?
hydrolysis
The hydrocarbon chains found in fats store a lot of energy. They also make fats ____________________, or insoluble in water.
hydrophobic
Remember that molecules that are soluble in water are hydrophilic. Molecules that are not soluble in water are hydrophobic. During their digestion and absorption in the small intestine, fats are packaged into hydrophilic forms. Drag the labels onto the flowchart below to indicate whether the bolded structures are hydrophilic or hydrophobic. Labels may be used once, more than once, or not at all.
hydrophobic ----> hydrophobic ----> hydrophobic ----> hydrophilic
The brain region that most directly integrates the endocrine and nervous systems in mammals is the __________.
hypothalamus
Which of these glands secretes releasing hormones?
hypothalamus
During a fever, the __________ readjusts the set point of the body to a __________ temperature.
hypothalamus; higher
Which letter indicates the vessels in which blood pressure is the lowest?
i
Chromatids are __________.
identical copies of each other if they are part of the same chromosome
If a plant variety is true-breeding for a dominant trait, then __________.
if the plant were allowed to self-pollinate, all of the progeny would have the dominant trait
Which of the following characteristics describes the thin segment of the ascending limb of the loop of Henle?
impermeable to H2O, permeable to NaCl
In insects, ecdysteroid is released __________.
in response to prothoracicotropic hormone
How does DNA (deoxyribonucleic acid) encode information
in the sequence of nucleotides
The heater turns on, and the temperature in the room _______________ until it returns to the original setting.
increases
An electrically neutral molecule has the formula C3H4O2N. If the carbon atoms form the usual number of bonds, how many covalent bonds will each hydrogen atom have with other atoms in the molecule?
1
For every 1.0 mole of glycine in the sample, how many molecules of methionine are present? (For help performing calculations with numbers expressed in scientific notation, try this exercise.)
1.08 × 1021 molecules of methionine
A mole (abbreviated mol) is defined as an exact number of objects: 6.02 × 1023 (Avogadro's number). You can have 1 mole of an atom, a molecule, or any other object, such as eggs or books. One mole of an object equals 6.02 × 1023 of that object. The table shows the "molar ratios" of some of the products from the Miller H2S experiment. In a molar ratio, each unitless value is expressed relative to a standard for that experiment. Here, the standard is the number of moles of the amino acid glycine, which is set to a value of 1.0. For instance, serine has a molar ratio of 3.0 × 10-2, meaning that for every mole of glycine, there is 3.0 × 10-2 mole of serine present in the sample. What is the molar ratio of methionine to glycine in the samples?
1.8 × 10-3 mole of methionine per mole of glycine
To fill the valence shell, an electrically neutral, unbonded atom with atomic number 8 must add .
2 electrons
Glycine's molecular formula is C2H5NO2. How many moles of each element would be needed to make 1.0 mole of glycine?
2 moles carbon, 5 moles hydrogen, 1 mole nitrogen, and 2 moles oxygen
What is the maximum number of moles of serine that could be made in the flask if no other molecules were made?
2/3 (0.67) of a mole of serine
What is the maximum number of moles of methionine that could be made in the flask if no other molecules were made?
2/5 (0.4) of a mole of methionine
An atom's atomic number is 7. Its valence is most likely ...
3
In molecules, C, H, O, and N atoms usually make __, __, __, and __ bonds respectively.
4, 1, 2, 3
How many molecules of glycine are present in 1.0 mole of glycine?
6.02 × 1023 molecules
Select the statement that best describes a buffer.
A buffer resists change in pH by accepting hydrogen ions when acids are added to the solution and donating hydrogen ions when bases are added.
What happens when two atoms form a chemical bond?
A chemical bond forms when two atoms transfer or share outer electrons to complete their outer shells.
A buffer consists of undissociated acid (HA) and the ion made by dissociating the acid (A-). How does this system buffer a solution against decreases in pH?
A- reacts with H+ to become HA.
The ammonia molecule in the diagram has the observed bond orientation because ... electrons repel one another. N has 7 protons in its nucleus. N has four pairs of electrons in the valence shell. All of the above.
All of the above
Which statement is true of water's tensile strength? (a) It results from hydrogen bonding. (b) It helps to pull water through plants.(c) It involves both cohesion and adhesion. (d) all of the above
All of the above
Two C atoms form a double bond. Each C is bound to two H atoms. Which statement is true?
All the atoms lie in a plane.
Which answer helps to explain why all living cells need pH buffers?
Amino acid side chains have many carboxyl and amino groups.
Electrons are held in an atom by attraction to what particle or location?
Attraction to the positively charged protons in the nucleus
Partial charges occur when ... (a) a covalent bond links atoms of two kinds. (b) atoms share electrons unequally. (c) two ions are close together both (a) and (b).
Both A and B
Water is a source of ______________ for chemical reactions in cells. (a) hydrogen atoms (b) oxygen atoms (c) energy Both (a) and (b)
Both A and B
Which factor is important in making it possible to cool yourself by sweating? Think carefully! (a) Molecules collide with varied angles and speeds. (b) Hydrogen bonds are relatively weak. (c) Water has more energy at the body surface. Both (a) and (b).
Both A and B
What type of bond is joining the two hydrogen atoms?
Covalent
A substance that cannot be broken down into other substances by ordinary chemical procedures is a(n) _____
Element
No amino acid molecule by itself can speed up or catalyze reactions between other molecules; however, when amino acids are joined together to make a protein with catalytic properties, the new structure (enzymatic protein) can speed up the rate of a specific chemical reaction. What does this illustrate?
Emergent properties
The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound.
H2S
Because organisms are made primarily of water, they resist rapid temperature changes. This useful quality is based on water's _____.
High specific heat
Most organic compounds contain carbon and _____.
Hydrogen
Which of these bonds is weakest?
Hydrogen Bonds are weaker than covalent bonds because they do not involve sharing of electrons, and they are weaker than ionic bonds because they involve the attraction of partial (not full) opposite charges.
The synthesis of products is limited by the amount of reactants added to the reaction flask. If one mole each of CH4, NH3, H2S, and CO2 is added to 1 liter of water in a flask (1 liter of water = 55.5 moles of H2O), how many moles of hydrogen, carbon, oxygen, nitrogen, and sulfur are in the flask? Round your answers to the nearest whole number. Hydrogen- Carbon- Oxygen- Nitrogen- Sulfur-
Hydrogen- 120 Carbon- 2 Oxygen- 58 Nitrogen- 1 Sulfur- 1
What does it mean to say that a gene is expressed?
Information in DNA is used to make a protein.
How does the way a buffer stabilizes pH during addition of acid differ from the way the same buffer stabilizes pH during addition of base?
It's the same reaction running backward or forward.
What kind of effect does R-dopa have on Parkinson's disease?
None.
Competition is central to the theory of natural selection. Why does competition occur?
Organisms typically produce too many offspring, and resources are limited.
L-dopa is used to treat _____.
Parkinson's disease
Which statement must be mentioned in explaining why amphipathic molecules line up at a water surface?
Polar groups attract one another.
(a) aquatic life to exist at the North Pole
Polar molecules attract one another
Changing the number of _____ would change an atom into an atom of a different element.
Protons in an atom
By making two covalent bonds, an O atom (with 8 protons) fills its valence shell. Why does the atom's charge stay close to zero?
Shared electrons aren't always near oxygen.
Why doesn't a skin cell make crystallin protein?
Skin cells have the crystallin gene but do not express it. Skin cells do not need crystallin for their function
Electron (pick two) (Symbol P, Symbol N, Symbol E, +1 charge, -1 charge, 0 charge)
Symbol E -1 charge
Neutron (pick two) (Symbol P, Symbol N, Symbol E, +1 charge, -1 charge, 0 charge)
Symbol N 0 charge
Proton (pick two) (Symbol P, Symbol N, Symbol E, +1 charge, -1 charge, 0 charge)
Symbol P +1 charge
Look at the figure showing the pH values of some familiar aqueous solutions. What is the difference between H+ concentration in an acidic solution such as lemon juice (pH 2) and a basic solution such as household bleach (pH 13)?
The H+ concentration of lemon juice is higher than the H+ concentration of household bleach by a factor of 1011 (100 billion).
Which of the following attributes is common to both prokaryotic cells and eukaryotic cells?
The use of DNA as the information storage molecule
Which answer helps to explain why carbon atoms tend to make 4 covalent bonds?
The valence shell needs 8 electrons.
Which statement is true of pH buffers?
They consist of weak acids and weak bases.
Which of the following statements is true about chemical nutrients in an ecosystem?
They recycle within the ecosystem, being constantly reused
Which statement about weak bonds is correct?
Weak bonds are transient and easily reversible.
Which of these examples illustrates deductive reasoning?
You learned in elementary school that as temperature drops, liquids change into solid form. You are given an unfamiliar liquid and predict that it will become solid if you put it in the freezer.
Dissolving is best described as ..
a mingling of molecules and/or ions.
Buffers work best when ..
about half of the buffer molecules are dissociated.
Which amino acid is present in higher amounts than glycine in the samples?
alanine
An ionic bond involves _____________________
an attraction between ions of opposite charge
The open spaces in water's crystal structure make it possible for ...
aquatic life to exist at the North Pole
Many of water's emergent properties, such as its cohesion, its high specific heat, and its high heat of vaporization, result from the fact that water molecules _____.
are attracted to each other by partial negative and positive charges on the oxygen and hydrogen atoms, respectively
Atoms with the same number of protons but with different electrical charges _______________
are different ions
In animal populations, DDT causes _____
birth defects
If only methionine (C5H11NO2S) was made, which element would be used up first?
carbon
If only serine (C3H7NO3) was made, which element would be used up first in the flask?
carbon
A(n) _____ bond joins these two oxygen atoms.
double covalent
The tendency of an atom to pull electrons toward itself is referred to as its _____.
electronegativity
In a double covalent bond, a carbon atom shares ...
electrons in two orbitals.
These molecules are _____.
enantiomers
The brackets are indicating a(n) _____ bond.
hydrogen
Water has surface tension because ...
hydrogen bonds between surface water molecules resist being stretched
In a neutral solution the concentration of _____.
hydrogen ions is equal to the concentration of hydroxide ions
In salt, what is the nature of the bond between sodium and chlorine?
ionic
Though you add heat, the temperature of boiling water remains constant because ...
it takes energy to break hydrogen bonds
When an electron absorbs the required amount of light energy, it moves from a ____________ electron shell to a ________________electron shell, which is _______________from the nucleus. lower/higher lower/higher farther from/ closer to
lower, higher, farther form
What is the correct order for the hierarchy of biological organization from the least to the most complex?
molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem
The unequal sharing of electrons within a water molecule makes the water molecule _____.
polar
In this molecule, what type of bond is found between the oxygen and hydrogens?
polar covalent
Without making or breaking bonds, the pictured molecule can change its shape because .
rotation can occur around single bonds.
What type of bond joins the carbon atom to each of the hydrogen atoms?
single (nonpolar) covalent
Chemical equilibrium is reached when _____.
the forward and reverse reactions occur at the same rate so that the concentrations of reactants and products remain the same
Which property of water allows dogs to cool themselves by panting?
water's high heat of vaporization
