CH275 Exam&Quiz Questions
A man and a woman who are both carriers of cystic fibrosis have had three children without cystic fibrosis. If the couple has a fourth child, what is the probability that the child will have the disorder?
25%
How many nucleotides are required to code for 10 amino acids?
30
What is the maximum number of single covalent bonds a carbon atom can form with other elements?
4
An uncharged atom of gold has an atomic number of 79 and an atomic mass of 197. This atom has ______ protons, ______ neutrons, and ______ electrons.
79,118,79
A sexually reproducing animal has two unlinked genes, one for head shape (H) and one for tail length (T). Its genotype is HhTt. Which of the following genotypes is possible in a gamete from this organism? EB Ee B EeBb
A
According to mendels law of segregation A)gametes have one allele copy for each gene B)gametes are diploid C)two of the same allele segregates into each gamete D)more gametes carrying the dominant allele are produced than gametes carrying the recessive allele
A
After replication, A) each new DNA double helix consists of one old strand and one new strand B) each new DNA double helix consists of two new strands C) each new DNA double helix consists of two old strands
A
Amanda's parents realized that her body was not developing properly about the time she was 12 years old. She was shorter than most of her friends and was not going through changes normally associated with female puberty. They took her to a doctor who initially diagnosed Amanda with Turner Syndrome because of her physical features. He ordered a karyotype that confirmed his diagnosis. Amanda was born with only one X chromosome. Although there is no specific cure, the doctor was able to treat her and correct some of the problems associated with the condition. For example, she received growth hormone to improve her growth and estrogen to help her develop the physical changes of puberty. Amandas abnormal number of sex chromosomes resulted from: A) nondisjunction B) crossing over C) independent assortment of chromosomes D)random fertilization
A
Cancer cells are cells that A) do not respond normally to cell cycle control system B) produce toxins that kill surrounding cells C) always develop in response to abnormally high doses of radiation D) do not require oxygen
A
Deep Vein Thrombosis occurs when blood clots emerge in the legs. When these blood clots are dislodged in the vein, they return to the heart, which is then passed to the lungs. In the lungs, the blood clot can become lodged and cause a pulmonary embolism, which can be fatal if not treated quickly. Why can a pulmonary embolism be fatal? A CO2 rich blood cannot exchange with O2, preventing O2 being pumped to vital organs B The blood clot prevents O2 rich blood from returning to the heart C CO2 rich blood cannot return to the heart through the pulmonary vein and pass to vital organs D The blood clot could clog the aorta, preventing O2 rich blood being pumped to vital organs.
A
If a solution has a pH of 2, how does its H+ ion concentration compare to a solution with a pH of 5? A) 1000x higher B) 3x higher C) 10x higher D) 100x higher
A
If a strand of DNA has the sequence TCATTG, transcription will result in ______ A)single RNA strand with the sequence AGUAAC B)DNA double helix with the sequence AGTAAC for one strand and TCATTG for the complementary strand C)single RNA strand with the sequence CTGCCA D)RNA double helix with the sequence AGUAAC for one strand and UCAUUG for the complimentary strand
A
If guanine makes up 30% of the bases in DNA double helix, what percent of the bases is adenine? A) 20% B)50% C)60% D)40%
A
Plants are susceptible to bacterial infections, which can damage their structure or even kill them. Which of the following would be the best antibiotic to treat a plant that is infected with bacteria? A) a drug that blocks gene expression in circular chromosomes B) drug that destroys the central vacuole C) drug that disrupts celluose production D) drug that interferes with mitochondria function
A
Tay-Sachs disease is a human genetic abnormality that results in cells accumulating very large, complex, undigested lipids. Which cellular organelle must be defective in this condition? A)the lysosome B)the endoplasmic reticulum C)the Golgi apparatus D)mitochondrion
A
What is the key to the recognition of codominance? A The heterozygote expresses the phenotype of both homozygotes. B The trait exhibits a continuous distribution. C The alleles affect more than one trait. D The phenotype of the heterozygote is intermediate between the phenotypes of the homozygotes.
A
Which of the following best describes the difference in the way B cell and T cells deal with invaders? A B cells produce antibodies that bind to invaders; T cells directly engage cells infected by the invaders by recognizing antigen fragments. B B cells provide permanent immunity; T cells provide temporary immunity C B cells are always ready "off the rack" to respond to an invader; T cells must be primed. D T cells handle the primary immune response; B cells handle the secondary immune response.
A
Which of the following statements is an example of negative feedback? : A An increase in the concentration of glucose in the blood stimulates the pancreas to secrete insulin, a hormone that lowers blood glucose concentrations. B Hypertension damages the lining of the arterioles of the kidneys, which results in the release of molecules that further raise blood pressure. C Stimulation of a nerve cell causes sodium ions to leak into the cell, and the sodium influx triggers inward leaking of more sodium. D During child labor, pressure on the cervix causes the release of oxytocin by the pituitary gland which triggers increased contractions and release of more oxytocin.
A
Which reasoning is a plausible explanation for why it may be difficult to treat infections that arise from tooth decay? A Bacteria of the biofilm that cause tooth decay form a symbiotic relationship with the antibiotics and therefore diminish antibiotic effectiveness. Binary fission in biofilm bacteria that cause tooth decay begins to decrease as the biofilm community becomes more complex, thereby producing fewer bacterial cells for antibiotics to penetrate. C Biofilm bacteria that cause tooth decay begin to produce endospores as a means to deter effects of antibiotics.
A
Which stage occurs in the cytoplasm? A) gycolysis B) citric acid cycle and electron transport C) citric acid cycle D) glycoloysis and citric acid cycle
A
Why does iron deficiency cause blood to become anemic? A) iron is integral for hemoglobin, as it binds O2 to heme group B) iron signals stem cells in bone marrow to produce more red blood cells C) iron prevents the binding of carbon monoxide D) iron is required to build strong and healthy muscles
A
amino acid is to protein as A) nucleotide is to nucleic acid B) monosaccharide is to lipid C) monosaccharide is to nucleic acid D) DNA is to RNA
A
what is the difference between an autoimmune and an immunodeficiency disease? A An autoimmune disease is a condition arising from an abnormal immune response to a normal body part; whereas an immunodeficiency disease is a condition in which one or more parts of the immune system are defective. B An autoimmune disease is a condition in which one or more parts of the immune system are defective is a condition arising from an abnormal immune response to a normal body part; whereas an immunodeficiency disease is a condition arising from an abnormal immune response to a normal body part. C There is no difference between the two types of diseases.
A
which of the following are adaptations that appeared in the gymnosperms enabling them to adapt to a drier and colder climate? A All of these choices are correct B The evolution of pollen C The evolution of the seed D Reduction of the gametophyte
A
All of these statements about the circulatory system are true, except: A mammals have a four-chambered heart. B veins are lined by smooth muscles that contract and push blood back to the heart. C oxygenated blood is typically transported in arteries. D the systole phase of the cardiac cycle involves contraction and increased blood pressure
B
An original section of DNA has the base sequence AGCGTTACCGTT. A mutation in this DNA strand results in the base sequence AGGCGTTACCGTT. This change represents _____. A point mutation B frameshift mutation C missense mutation D silent mutation
B
Hemophilia is a sex-linked recessive gene that causes a blood disorder. What are the chances that the daughter of a normal man and a heterozygous woman will have hemophilia? A)25% B)0% C)50% D)75% E)100%
B
Hydrogen bonds differ from covalent bonds in that A)hydrogen bonds are much stronger than covalent bonds. B)hydrogen bonds arise from intermolecular forces while covalent bonds arise from intramolecular forces. C)hydrogen bonds involve the sharing of elecctrons while covalent bonds involve the transfer of electrons. D) hydrogen bonds only involve hydrogen and oxygen while covalent bonds never involve hydrogen and oxygen.
B
Imagine that a scientist discovers a mutant plant seedling that appears to lack stomata. What would be the effect of this? A)Additional ATP would be produced by the seedling, and the plant would grow taller. B)CO2 would not be able to enter the plant as a reactant for photosynthesis. C)Visible wavelengths of light would be unable to reach the chloroplasts. D)Glucose would not be able to enter the plant as a reactant for photosynthesis.
B
Once researchers identified DNA as the unit of inheritance, they asked how information was transferred from the DNA in the nucleus to the site of protein synthesis in the cytoplasm. What is the mechanism of information transfer in eukaryotes? A) Transfer RNA takes information from DNA directly to a ribosome, where protein synthesis takes place. B)Messenger RNA is transcribed from a single gene and transfers information from the DNA in the nucleus to the cytoplasm, where protein synthesis takes place. C)Proteins transfer information from the nucleus to the ribosome, where protein synthesis takes place. D) DNA from a single gene is replicated and transferred to the cytoplasm, where it serves as a template for protein synthesis.
B
Scientist isolate cells in various phases of the cell cycle. They find a group of cells that have 1.5 more DNA than G1 phase cells. The cells of this group are ___ A) in the G2 phase B) in the S phase C) between the G1 and S phases D) in the M phase
B
Sequencing eukaryotic genomes is more difficult than sequencing genomes of bacteria or archaea because of the _____. A hard-to-find proteins B large size of eukaryotic genomes and the large amount of eukaryotic repetitive DNA C large size of eukaryotic proteins D high proportion of G-C base pairs in eukaryotic DNA
B
The absence of a terminator in trancription will result in A)a strand of mRNA that lacks its cap and tail B)the production of a longer RNA molecule C)the production of a shorter RNA molecule
B
The following are terrestrial adaptations that enabled plants to adapt to life on land except: A protected gametes and embryos B the ability to perform photosynthesis C the cuticle for water retention D vascular tissue to transport vital materials
B
Traits controlled by sex-linked recessive genes are expressed more often in human males because: A) males get more doses of the recessive gene than do females B) male has only one gene for the trait C) males inherit these genes from their fathers more often than their mothers. D) males always carry two copies of these genes
B
What kind of bond is found between the individual atoms of a single water molecule? A) nonpolar covalent bonds B) polar covalent bonds C) ionic bonds D) hydrogen bonds
B
Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? A)Hydrolysis creates monomers, and dehydration reactions destroy them. B)Dehydration reactions assemble polymers, and hydrolysis breaks them down. C)Dehydration reactions occur only in animals, and hydrolysis reactions occur only in plants. D) Hydrolysis creates polysaccharides, and dehydration creates monosaccharides.
B
Which of the following is an adaptation to increase the surface area of a part of a cell that is involved in cellular respiration? A)the endoplasmic reticulum B)the cristae of a mitochondrion C)the outer membrane of a chloroplast D)the grana of a chloroplast
B
Which of the following statements is incorrect regarding DNA and RNA? A)DNA is double stranded, and RNA is a single strand. B)They each contain the same sugar molecule. C)DNA contains more nucleotides than RNA. D)One of the bases is different.
B
Which of these components is a part of the innate immune system? A antibodies B phagocytic cells C B cells D helper t cells
B
in the sequence of events during translation, what is the next step after an mRNA binds to the ribosome's small subunit? A)A tRNA enters the A site of the ribosome. B)A tRNA binds to the start codon, and the large ribosomal subunit joins the ribosome. C)An amino acid from a tRNA in the P site attaches to an amino acid on the tRNA in the A site. D)The ribosome shifts down the mRNA by one codon.
B
the liver is involved in the detoxification of many poisons and drugs. which of the following structures in primarily involved in this process ad therefore abundant in liver cells? A) nuclear envelope B) smooth ER C) rough ER D) lysosomes
B
the phylum chordata does not contain which of the following characteristics? A) pharyngeal slits B) webbed feet C) a dorsal hollow nerve chord D) a notochord E) a post-anal tail
B
which of the following organisms was the first to introduce oxygen into the earth's atmostphere? A plants B cyanobacteria C early protozoans D fungi
B
(LO 6.1) Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol.Running burns approximately 600 Calories per hour. If you ate four hard-boiled eggs, how long would you have to run to burn them off? A) 120 min B) 10 min C) 30 min D) 60 min
C
A cell that completed the cell cycle without undergoing cytokinesis would ______. A) not completed anaphase B) have its chromosomes lined up in the middle of the cell C) have two nuclei D) have less genetic material than it started with
C
All of the following are benefits of sequencing the human genome EXCEPT A) lead to treatments for inherited diseases B) genes were discovered whose functions were previously unknown C) every genetic disorder is now curable or preventable D) increase our understanding of the historical relationships among species
C
Imagine that there are twenty-five different species of protists living in a tide pool. Some of these species can reproduce both sexually and asexually. The pool gradually becomes infested with disease-causing viruses and bacteria. Which type of reproduction is favored under these conditions? A) somatic reproduction B) asexual reproduction C) sexual reprodcution D) sexual and asexual are equally favored
C
Information flow in biological systems is necessary for feedback to operate. Which of these examples does not involve flow of information providing feedback? A)Bacterial genes for breaking down lactose are activated in the presence of lactose. B)Heat receptors send signals to promote sweating. C)Drought kills many trees. D) Low blood sugar causes the liver to convert starch to sugar to be released in the blood.
C
One difference between eukaryotic and prokaryotic cells is that eukaryotic cells _______ prokaryotic cells. A) have a nucleoid region, which is lacking in B) have DNA, which is lacking in C) have membrane enclosed structures called organells, which are lacking in D) Have a plasma membrane, which is lacking in
C
Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, Taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, Taxol must affect A) s phase of the cell cycle B) chromatide assembly C) structure of mitotic spindle D) formation of centromere
C
The production of fruits and flowers in angiosperms increase their survivability and genetic variability for all of the following reasons EXCEPT _______________. a) It allows them to be fertilized independent of wind. B It allows their seeds to be protected prior to fertilization. C It allows them to out-compete their gymnosperm counterparts. D It allows them to be pollinated independent of wind.
C
What characteristic of short tandem repeats DNA make it useful for DNA fingerprinting? A Every racial and ethnic group has inherited different short tandem repeats. B The sequence of DNA that is repeated varies significantly from individual to individual. C The number of repeats varies widely from person to person or animal to animal. D The sequence variation is acted upon differently by natural selection in different environments.
C
What would enable a single RNA transcript to be translated into different polypeptides? A)The length of the RNA transcript tail can vary. B)Two different genes can produce the same RNA transcript, which will then be translated differently. C)The RNA transcript can be spliced more than one way. D)The coded polypeptide can only be modified one way
C
Which is a characteristic of the lytic cycle? A Viral DNA is incorporated into the host genome. B The virus—host relationship usually lasts for generations. C A large number of phages are released at a time. D The viral genome replicates without destroying the host.
C
Which of the following can not easily diffuse through the plasma membrane? A) benzene B) CO2 C) glucose D) O2
C
Which of the following description best fits the class of molecules known as nucleotides? a nitrogenous base and a phosphate group a phosphate group and an adenine or uracil a nitrogenous base, a phosphate group, and a sugar a nitrogenous base and a sugar
C
Which of the following has the lowest OH- concentration? A)a solution with a pH of 14 B)a solution wiht a pH of 7 C)a solution with a pH of 1 D)a solution with a pH of 4
C
Which of the following statements about the cytoskeleton is true? A)The cytoskeleton of eukaryotes is a static structure most resembling scaffolding used at construction sites. B)Although microtubules are common within a cell, actin filaments are rarely found outside of the nucleus. C)Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other. D) Chemicals that block the assembly of the cytoskeleton would have little effect on a cell's response to external stimuli.
C
Which of the following statements about the properties of life is false? A)Organisms have the ability to take in energy and use it. B)Organisms have the ability to reproduce. C)Organisms have an unchanging, constant internal environment D)Organisms have the ability to respond to stimuli from the environment.
C
Which of these statements is correct? A)Single, haploid (2n) sets of chromosomes in ovum and sperm unite during fertilization, forming a diploid (4n), single-celled zygote. B)In humans, the twenty-second pair, the sex chromosomes, determines whether the person is female (XY) or male (XX). C)Ovaries and testes produce haploid gametes by meiosis. D)In humans, each of the twenty-three maternal autosomes has a homologous paternal chromosome.
C
Why does transcription occur in the nucleus and not in the cytoplasm in eukaryotes? A) ribosomes cant leave the nucleus B) RNA cannot exist in cytoplasm C) DNA cannot leave nucleus
C
during his trip on the beagle, darwin found that____ A fossils found on a particular continent were clearly not related to the plants and animals living on that continent today B plants and animals living in temperate regions were most similar to each other, regardless of the continent on which they were found C plants and animals living on a continent seemed more closely related to each other than to plants and animals living in similar regions on other continents D plants and animals were similar on every continent and in every type of region
C
The DNA sequence CAT codes for an amino acid carried by a tRNA with the anticodon _______
CAU
The calvin cycle makes direct use of ___ to make ___
CO2, ATP, NADPH.....sugar
A child is born with a rare disease in which mitochondria are missing from certain skeletal muscle cells. Physicians find that the muscle cells function. Not surprisingly, they also find that ________. A)the muscles require extremely high levels of oxygen to function B)the muscle cells cannot split glucose to pyruvic acid C)the muscles contain large amounts of carbon dioxide following even mild physical exercise D)the muscles contain large amounts of lactic acid following even mild physical exercise
D
A mutation within a gene that will insert a premature stop codon in mRNA would___ A)result in a longer polypeptide chain B)have the same effect as deleting a single nucleotide in the gene C)change the location at which transcription of the next gene begins D)result in a shortened polypeptide chain
D
An experiment is conducted in which two groups of identical plants (group 1 and group 2) are given equal and adequate amounts of sunlight and carbon dioxide. Each group contains five plants. Group 1 is given an optimal amount of water, while Group 2 is given a sub-optimal amount of water. In comparison to the plants in group 1, a scientist would expect the plants in group 2 to have A) increased plant growth B) increased sugar production C) increased amounts of oxygen released D) decreased amounts of ATP being produced
D
Echinoderms are considered the closest relatives of the chordates and share what following characteristic? A vertebrae B an exoskeleton made of chitin C ability to perform photosynthesis D similar early embryonic development
D
How does your immune system produce enough of the right cells to fight off a major infection? A) immune system attacks cells B) adaptive system is always primed and ready to go C) innate immune respongs tags pathogens for destruction and makes memory cells D) clonal selection causes antigen to activate select lymphocytes with specific antigen receptors
D
In an experimental situation, a student researcher inserts an mRNA molecule into a eukaryotic cell after she has removed its 5′ cap and poly-A tail. Which of the following processes would you expect her to find to have occurred? AThe cell adds a new poly-A tail to the mRNA. BThe mRNA attaches to a ribosome and is translated, but more slowly. CThe mRNA is quickly converted into a ribosomal subunit. DThe molecule is digested by enzymes because it is not protected at the 5′ end.
D
Of the following metabolic processes, which is common to photosynthesis and cellular respiration? A)reactions that convert CO2 to sugar B)reactions that split H2O molecules and release O2 C)reations that convert light energy to chemical energy D)reactions that store energy by pumping hydrogen ions (H+) across membranes
D
What is the function of proteases in the digestion process? A These enzymes break down nucleic acids into nucleotides. B These enzymes break down large polysaccharides into smaller carbohydrates. C These enzymes break down fats into glycerol and three fatty acids. D These enzymes break down large proteins into smaller peptides for absorption.
D
What is the result when a well-tested hypothesis is supported by many independent studies in the scientific community? A) hypothesis can now be referred to as a prediction B) hypothesi is a fact that cannot be refuted C) further experiments would not occur unless a sufficient alternative is proposed D) hypothesis would be considered a scientific theory
D
What would you assume if you found RNA transcripts of lactose-utilizing genes within E. coli? A) lactose has bound to the lac operon activator. B)The lac operon repressor protein is present in the cell. C)The lac operon activator protein is present in the cell. D)Lactose is present in the cell.
D
Which group of fishes includes a lineage that migrated out of fresh water and adapted to life on land? A cartilaginous fishes B ray finned C jawless D lobe finned
D
Which of the following processes occurs during transcription? A) mRNA attaches to ribosomes B) DNA is replicated C) proteins are syntehsized D) RNA is synthesized
D
a man who has B blood and a woman who has type A blood could have children with which of the following phenotypes? A) AB or O B) AB only C) A,B,O D) A,B,AB, O
D
all of the following occur during DNA replication except A separation of parental DNA strands. B use of parental DNA as a template. C use of DNA polymerase enzymes. D synthesis of two new double-stranded RNA molecules.
D
which of the following is a physiological response that takes place in humans when they get too hot? A) muscles contract B) increased metabolic rate C) constrictio of blood vessels in skin D) dilation of blood vessels in skin
D
which of the following is required for natural selection to occur? A equal access to all required nutrient by members of a population B inheritable variation among the organisms in a population C production of more offspring than can survive D differential reproduction among organisms in a population
D
prokaryotes are classified into
Domain Bacteria and Domain Archaea
The DNA sequence GTA codes for an amino acid carried by a tRNA with the andicodon
GUA
If a tRNA molecule that is specialized for the transfer of the amino acid valine has the anticodon CAG, it will couple with the codon
GUC
Translation converts the information stored in ______ to ______.
RNA; a polypeptide
What is it about carbon-12, carbon 13, and carbon 14 that makes them all carbon? A) They all are elements. B)They all have the number of protons that is characteristic of carbon. C)They all have the number of neutrons that is characteristic of carbon. D) They all have the number of protons plus neutrons that is characteristic of carbon.
They all have the number of protons that is characteristic of carbon.
Under the biological species concept, what criterion is used to assign populations of organisms to the same biological species?
ability to interbreed and produce fertile offspring
Based on current knowledge about the conditions of the early Earth, the first organisms were most likely
anaerobic prokaryotes
A leech belongs to which phylum?
annelida
What type of reproductive isolating mechanism is described by a situation in which female fireflies mate only with males who emit light in a particular pattern?
behavioral isolation
All plants exhibit alternation of generations. In which group of modern plants is the gametophyte the dominant generation?
bryophytes
Which element forms the structural basis of organic compounds?
carbon
Which structure can perform all the activities required for life?
cells
microevolutions occur when______
changes in allele frequencies in a population occur over generations
What type of tissue has widely scattered cells embedded in an extracellular matrix?
connective tissue
Enzymes increase the rate of a reaction by
decreasing the activation energy
When a base is added to a buffered solution, the buffer
donate H+ ions
If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in the diploid state?
fertilization
what is hypothesized to be the 3rd stage of the process that led to the abiotic origin of life?
formation of pre-cells
Genetically modifying human ____ may directly affect future generations of offspring A) muscles B) brain cells C) gametes D) skin cells
gametes
What does it mean when we say a gene is "turned off"?
gene is not transcribed
crossing over during prophase results in
genetic recombination
When mixed with water, phospholipids spontaneously form membranes because they ______.
have hydrophilic phosphate groups that are attracted to water and hydrophobic fatty acid tails that avoid water
The forearms of humans, bats, whales, and cows all have different functions, yet all have the same basic bone structure due to Darwin's descent with modification hypothesis. These types of structures are referred to as _________
homologous structures
To determine the genotype of an individual who expresses a dominant trait, you would cross that individual with an individual who is
homozygous recessive
The cohesive and adhesive properties of water are due to ______ bonds between separate water molecules.
hydrogen
what holds the complementary strands of a DNA molecule together?
hydrogen bonds
The bond between oppositely charged ions is an
ionic bond
If DNA directs the production of mRNA, what is the purpose of mRNA?
mRNA is translated into proteins
According to the theory of endosymbiosis, which organelles evolved from small prokaryotes that established residence within other, larger prokaryotes?
mitochondria and chloroplasts
tumor suppressor genes_____
normally surpress tumor growth
Energy is transferred from ATP to other molecules by transferring a(n) ______.
phosphate group
You find a type of cell you have never seen before. The cell has both a nucleus and a cell wall. Therefore you conclude that it is likely to be a ____ cell
plant
Which of the following describes multiple genetic loci that affect the expression of one trait?
polygenic
region of DNA where RNA polymerase binds is the
promoter
Which nucleic acid is an enzyme, that stabilizes and orientes the different amino acids to facilitate the formation of bonds between them during translation?
rRNA
function of a mushroom or puffball?
release and spread fungal spores
Which enzyme is used to produce sticky ends in plasmids?
restrictive enzyme
What does it mean to say that experimental results are peer reviewed?
results are analyzed by other scientists before they are published
Where does protein synthesis occur?
ribosomes
Which type of reproduction is most adaptive in a rapidly changing environment?
sexual reproduction
most absorption of nutrients occurs in the
small intestine
What is hypothesized to be the first stage of the process that led to the abiotic origin of life?
synthesis of small organic molecules
what is the main component of blood plasma?
water
