BIO181

The formation of the complex molecules in living organisms is made possible by what property or carbon?

Carbon forms up to 4 covalent bonds

Which level of organization is common to all life forms?

Cell

The equation, C6H12O6 + 6O2 → 6CO2 + 6H2O (ATP + heat), describes what process?

Cell respiration

What do contact-dependent signaling and paracrine signaling have in common?

Cells release a signal that affects neighboring cells

What structure easily distinguishes a plant cell from an animal or bacterial cell?

Chloroplast

Which of the following correctly describes bases that pair with each other in the DNA double helix?

Cytosine bonds with guanine

Where does glycolysis takes place?

Cytosol

The key structural difference between DNA and RNA is

DNA contains a different sugar than RNA

In Barrow, Alaska, the sun does not set for several months in the summer. Based on what you know about photoperiodism, what type of plant is most likely to flower during the summer in Barrow?

Day-neutral plants

Osmosis describes the movement of water from an area of high to low solute concentration

False

Saturated fats are composed of fatty acids with several double bonded carbons.

False

Substrate-level phosphorylation occurs when protons pass through ATP synthase and combine with oxygen to make water.

False

Table salt forms from sodium and chloride via hydrogen bonding.

False

The Calvin cycle is only capable of fixing carbon dioxide in the dark.

False

Vertical evolution, whereby living organisms evolve from a common ancestor ("tree of life"), is the only mechanism of evolution on Earth

False

What structural component makes fat an efficient macromolecule able to store large amounts of energy?

Fats have long chains of C-H bonds, which store large amounts of energy

The conversion of pyruvate to acetyl CoA is irreversible. Predict what would happen to fatty acids as a result of this.

Fatty acids cannot be converted into carbohydrates.

Our species is called Homo sapiens. The first word refers to which taxonomical grouping?

Genus

If you were asked to build a model of a nucleotide, what structures would you need to represent in the model?

-Five carbon sugar -Base -Phosphate group

With an atomic mass of 16 and an atomic number of 8, it follows that oxygen

-Has 8 electrons -Can readily form bonds with two other atoms

How many net ATP and NADH molecules are produced from one molecule of glucose during glycolysis?

2 ATP, 2 NADH

How many ATP and NADH molecules are produced from each molecule of glucose in the citric acid cycle only?

2 ATP, 6 NADH

If a specimen contains 30% adenine in its DNA then how much cytosine will there be?

20% (30+30) + (20 + 20) = 100

How many nucleotides are contained in a single codon?

3

The purpose of the light reaction is to produce __________.

ATP and NADPH

What is produced during the citric acid cycle?

ATP, NADH, and FADH2.

Plant photosynthesis and the consumption of plants by animals is best explained by what unifying principle of life?

All living organisms use energy.

How might a plant cell compensate for the excessive membrane fluidity that occurs during prolonged exposures to elevated temperature?

Alter the lipid composition to have longer phospholipid tails and fewer double bonds

How can a living cell increase the rate of a chemical reaction?

By using a catalyst

Which of these molecules are required for the Calvin cycle?

CO2 NADPH Rubisco ATP

Which of the following are physical stimuli that influence plant responses?

CO2, light, water vapor, gravity

What process best characterizes Ca2+ movement from the cytosol (low Ca2+ concentration) into the endoplasmic reticulum (high Ca2+ concentration)?

Calcium movement involves active transport

Which of the following are products of the Calvin cycle?

Glyceraldehyde-3-phosphate (G3P) ADP Pi NADP+

Which is not a lipid?

Glycogen

What processes will occur in the presence or absence of oxygen?

Glycolysis

Identify a reactant in the light reaction of photosynthesis.

H2O

Which of these organisms consume organic molecules to live?

Heterotrophs

What type of bonding is likely to occur between two water molecules or strands of DNA?

Hydrogen

Genes expressed at relatively constant levels in tissues regardless of variations in the animal's condition are called

constitutive genes.

The strongest chemical bonds are

covalent bonds

Where does glycolysis take place?

cytosol

Isotopes are different forms of the same element that

differ in their number of neutrons

How does an enzyme work to catalyze a reaction?

It lowers the activation energy of a reaction.

Which of the following statements in TRUE?

Many active genes are found in euchromatin, because proteins involved in transcription can easily access these regions of DNA.

The following mRNA transcript would result in which polypeptide sequence?5′-ACU UUC ACU AUG UUU UUA UCC UCC ACU CCU UGA-3′Use the following codons and the amino acids they encode.AUG = Start or Met; UUU, UUC = Phe; UUA, UUG = Leu; UCU, UCC = Ser; CCU, CCC = Pro; ACU, ACC = Thr; UGA = Stop.

Met-Phe-Leu-Ser-Ser-Thr-Pro

Assume each of the following letters represents an amino acid. Which type of gene mutation occurred to produce the following protein sequence?Normal: JAYBIRDCATPAWMutated: JAYBIRDBATPAW

Missense

In addition to ATP, what are the end products of glycolysis?

NADH and pyruvate

Water diffuses through certain organs such as the kidneys and bladder much faster than would occur by passive diffusion through a lipid bilayer alone. What accounts for this more rapid rate of water transport in these organs?

Presence of aquaporin channels for facilitated diffusion of water

Sickle cell anemia is a condition in which red blood cells exhibit a characteristic "sickle" shape. This arises from a mutation or change in one of the amino acids found in hemoglobin. A single amino acid mutation would directly affect a proteins ________ structure.

Primary

Points of control in eukaryotic gene expression include ____. (Check all that apply)

RNA processing translation transcription post-translation

The process that most involves the selective uptake of a specific cargo molecule into the cell through receptor binding and aggregation

Receptor-mediated endocytosis

Which factors are utilized by the cell to recognize the stop codon and disassemble the translation machinery?

Release factors

Why would a diet containing unsaturated fats that form triglycerides be better for an athlete when considering energy levels and health?

Saturated fats are packed closer together, making their breakdown for energy release less efficient and forming unnecessary fat deposits

Sodium concentrations are higher outside and glucose concentrations are higher inside the cell. Using the same membrane protein for Na+ and glucose transport, what is it called when a Na+ electrochemical gradient is used to drive glucose transport into the cell against its concentration gradient?

Secondary active transport

Subunits (monomers) sometimes build up to form a macromolecule (polymer). Which of the listed molecules is NOT a monomer of a polymer

Steroid

The movement of sucrose and H+ into the cell by the same membrane protein reflects the actions of what type of transporter?

Symporter

Which statement about RNA processing in eukaryotes is INCORRECT?

The excision of introns from pre-mRNA is the only modification required to produce a mature mRNA.

What makes phospholipids good at forming cellular membranes?

The polar and non polar regions create an amphipathic bilayer of phospholipids

In the equation, C6H12O6 + 6O2 → 6CO2 + 6H2O, ATP and heat would be on which side of the reaction?

The products because this is an exergonic reaction.

When considering nomenclature for scientific names, what is the difference between the two primates, Homo sapiens and Homo erectus?

They are animals of a different species.

Which protein influences the ability of RNA polymerase to transcribe genes?

Transcription factors

Which product(s) of nonstructural genes are never translated?

Transfer RNA and ribosomal RNA

Which membrane component is most important for allowing large, charged molecules to pass through the membrane?

Transmembrane proteins

A community is composed of different populations of animals and plants.

True

An mRNA molecule, which contains the information to make a polypeptide, is constructed using a DNA template.

True

Both eukaryotes and prokaryotes require a promoter region for gene transcription.

True

DNA is a double helix structure whose strands are held together by hydrogen bonds with A to T and C to G base pairing.

True

Diffusion is the movement of a molecule from an area of high to low concentration.

True

Diffusion is the movement of molecules from an area of high to low concentration

True

Glycolysis involves ten enzyme-catalyzed steps that can be grouped into three phases: energy investment phase, cleavage phase, and the energy liberation phase.

True

Ion gradients across the membrane drive numerous cellular functions

True

Lipids and carbohydrates can both be used by animals to store energy.

True

Loosely packed chromatin is said to be in an open conformation.

True

Photons from light can boost an electron to a higher energy state.

True

Plant behavior is defined as response to stimuli

True

Plant behavior is defined as response to stimuli.

True

Temperature, pH, and ionic concentrations each play an important role in the proper functioning of enzymes.

True

The presence of integral proteins allows membranes to be selectively permeable to certain molecules.

True

The primary structure of a protein ultimately determines its three-dimensional structure.

True

The termination of translation occurs when a release factor recognizes the stop codon.

True

When a molecule of NAD+ gains a hydrogen atom, the molecule becomes reduced.

True

When table salt dissolves in water, the salt is called the solute

True

Whether a signaling molecule operates locally or over long distances, it must bind to a specific receptor to elicit a cellular response.

True

Carbohydrate assembly occurs by

a dehydration reaction between monosaccharides that form polysaccharides and disaccharides

When NADP+ __________.

accepts electrons in the light reaction, it is reduced to form NADPH

The production of second messengers in signal transduction offers at least two advantages, speed and

amplification

If orange juice has a pH of 4 then it can be described as

an acidic solution

If orange juice has a pH of 4 then it can be described as

an acidic solution.

In photosynthesis, carbon dioxide gas is reduced and combines to form glucose. This is an example of

anabolism

In photosynthesis, carbon dioxide gas is reduced and combined to form glucose. This is an example of

anabolism.

Fats and fatty acids

are insoluble in water

Molecules are made up of __________.

atoms

A cell responds to a signal it sent. This is an example of

autocrine signaling

A cell secretes a growth factor that binds to receptors on its own membrane preventing it from proliferating. This is an example of

autocrine signaling

If the tight junctions in the intestine were disrupted

bacteria could move from the intestines into the bloodstream causing an infection

The phenomenon through which populations of organisms change over several generations is termed

biological evolution

For water to vaporize

both energy must be supplied and hydrogen bonds broken

A comparison of mitochondria and chloroplast shows that __________.

both generate ATP via a H+ electrochemical gradient

The organelles most likely to have to ability to divide and reproduce themselves like a cell would be

both mitochondria and chloroplasts

The addition of a strong acid like HCl to an aqueous solution would result in

both the release of H+ and a decrease in pH

The process of breaking glycogen down to glucose is an example of

catabolism.

The process through which cells can detect and respond to signals in their extracellular environment is called

cell communication

Where does the Calvin cycle occur?

chloroplast stroma

The best way to distinguish an epigenetic effect from other types of gene regulation would be to

confirm that the change in gene expression is passed from cell to cell but does not involve a change in the DNA sequence.

The organelle responsible for the biosynthesis of proteins that are destined for secretion by the cell is the

endoplasmic reticulum

Following a meal, glucose must move from the gut lumen where there is a high glucose concentration into the intestinal cell where there is a relatively low level of glucose. This movement is called

facilitated diffusion

Eukaryotes differ from prokaryotes, in part because eukaryote cells

have a membrane-bound nucleus.

A significant role played by pH buffers is to

limit major shifts in the amount of H+ and OH- in solution

Cyanide binds and impairs one of the molecules involved in the synthesis of ATP. The target organelle for cyanide must be

mitochondria

In the reaction A- + B → A + B-, ________

molecule A is oxidized and molecule B is reduced.

All of the following are a form of potential energy that can be used by a cell except

nitrogen.

A substrate binding to an enzyme is most similar to a signal molecule binding to a

receptor

The primary function of an enzyme or any biological catalyst is to

reduce the energy of activation and increase the rate of a reaction.

In a catabolic reaction, electrons from food are

removed by oxidation and stored in NADH.

An activator is to an enhancer as a(n) _____ is to a silencer.

repressor

In the Calvin Cycle, CO2 binds to __________.

ribulose bisphosphate

Glycogen is to animal cells as ________ is to plant cells.

starch

Roots contain starch-heavy plastids known as:

statoliths

The main structure for gas exchange in plants is called the __________.

stomata

The ATP made during glycolysis is generated by

substrate-level phosphorylation.

What serves as the "translator" or intermediary between an mRNA codon and an amino acid?

tRNA

The grouping or classification of a species is termed

taxonomy

Both ATP and NADPH are required for ___________.

the Calvin cycle only

The atomic number of an atom is

the number of protons in the atom

In all exergonic reactions

the reaction proceeds with a net release of free energy

In some cases, just a few hormone molecules binding to the surface of a cell can trigger a very large response because

the signal is amplified by activation of enzymes that each catalyze multiple reactions

The ultimate source of energy for reactions in a plant is __________.

the sun

A variety of finch species within the Hawaiian Islands have acquired different types of beaks needed for utilizing specific food resources. What is the likely process by which these different species of finches came about?

vertical descent with mutation

If you wanted to install lights to grow plants indoors, the type of light would you want to use is __________.

visible light, because it has low energy wavelengths

If you wanted to install lights to grow plants indoors, the type of light would you want to use is

visible light, becuase it has low energy wavelengths

What type of bonds form from the unequal sharing of electrons?

Polar covalent

Boa constrictors on an island are an example of a/an __________.

Population

NADPH is produced by __________.

light reactions alone

Which is the largest molecule?

A polysaccharide, starch

Which of the following base pairs would be targeted and repaired by a mismatch repair system?

A-G

________ bind two or more ions or molecules and transport them in opposite directions across a membrane.

Antiporters

_________ bind two or more ions or molecules and transport them in opposite directions across a membrane

Antiporters

Plants require a lot of water for transpiration, metabolism, and photosynthesis. How is water used in photosynthesis?

As an electron donor

In the periodic table, the value that refers to the number of protons and neutrons is

Atomic mass

Which is FALSE when comparing RNA and DNA?

Both are composed of the same types of nucleotides.

A bowl of sugar water is very stable. However, cells can rapidly break down sugar into carbon dioxide and water. What is the best explanation for this observation?

Enzymes in the cell catalyze the breakdown of glucose.

If a person's ability to form steroids in his/her body was destroyed, what functions would be affected?

Estrogen would no longer be produced in the body.

A dehydration reaction that builds larger molecules from smaller units requires the addition of a water molecule.

False

A single gene always encodes for a protein.

False

If the sequence for one strand of DNA is 3′-TCGATT-5′ then its complementary strand would have a sequence of 3′-AGCTAA-5′.

False

If there is 28% adenine, then there must be 28% cytosine for the DNA composition of a particular organism.

False

In prokaryotic cells, the electron transport system occurs in the mitochondria.

False

Metabolism refers to only those reactions that release energy.

False

If a cell's splicesomes were mutated so they no longer functioned normally, what consequences would result?

Introns would remain in the mature mRNA.

In water, MgCl2 dissociates into Mg2+ and Cl-. Based on this information what type of bond is involved in the formation of MgCl2?

Ionic

A researcher determined that a strain of E. coli is producing a shortened version of a protein required for glucose metabolism. What type of mutation could be responsible for this shorter than normal protein?

Nonsense mutation

Amino acid is to protein as as _______ is to nucleic acid

Nucleotide

The amino acids of a growing polypeptide chain are held together by what kind of bond during the elongation stage of translation?

Peptide

How does a macrophage (immune cell) consume a bacteria?

Phagocytosis

The equation, 6CO2 + 6H2O →C6H12O6 + 6O2, describes which process?

Photosynthesis

Sodium ions move from one cardiac muscle cell to an adjacent cell causing them to contract in unison. This is an example of

direct intracellular signaling

When one oxygen atom shares two pairs of electrons with another oxygen atom, O2 is formed via a(n)

double covalent bond

A community of organisms interacting with their physical environment is a/an

ecosystem

After ATP donates a phosphate group in a couple reaction, it becomes ADP. The ADP can be converted back to ATP in a(an) ________ reaction.

endergonic

Hormones are released from one cell and act on other cells in distant organs. This is an example of

endocrine signaling

When insulin is secreted from the pancreas and acts on muscle cells to increase glucose uptake, this is an example of

endocrine signaling

For heart muscles to beat in a coordinated rhythm ions must move from one cell to the next through ________.

gap junctions

You inject a dye into a cell and observe that it moves into adjacent cells. This would occur through ________.

gap junctions

A cell's ability to control their level of gene expression is called

gene regulation.

During a period of low water availability, the prokaryotic structure that would protect a cell from desiccation (drying out) is the

glycocalyx

Gravitropism is defined as

growth in response to the force of gravity

Water

has cohesive properties

Whether the external temperature is hot or cold, birds maintain an internal body temperature of approximately 40°C. This is an example of

homeostasis

When placed in an aqueous solution, amphipathic molecules will orient themselves with

hydrophobic hydrocarbon chains in the middle, and hydrophilic head groups facing the water.

A(n) ________ operon is one whose transcription is increased by effector molecules.

inducible

Intervening sequences that are transcribed, but not translated into protein are called

introns.

A dehydration reaction

is used to form polymers.

The LEAST hydrophilic substance is

oil

Cellular respiration produces the most energy in the form of ATP from

oxidative phosphorylation.

A cell secretes a growth factor that binds to receptors on neighboring cells causing them to proliferate. This is an example of

paracrine signaling

The organisms that most specifically utilize light energy to make organic molecules from inorganic molecules are __________.

photoautotrophs

Gap junctions in animal cells are most similar to ________ in plant cells?

plasmodesmata

During glycolysis, glucose is broken down into

pyruvate.

Water held behind a dam would best reflect

potential energy.

In a eukaryotic cell, the direct product of transcription is

pre-mRNA.

The sequence of amino acids in a protein is its _____ structure.

primary

The sequence of amino acids in a protein is its ______ structure.

primary

A plant performing photosynthesis will __________.

produce oxygen and consume carbon dioxide

A cell wall is present in

prokaryotic and plant cells

Transcription begins near a site in the DNA called the

promoter

The macromolecule composed of amino acids is a

protein

What structure best represents a polymer?

protein

The nucleus of an atom is composed of

protons and neutrons

During glycosis, glucose is broken down into

pyruvate

In the reation pyruvate + CoA + NAD+ > acetyl CoA + CO2 + NADH,

pyruvate is oxidized and NAD+ is reduced

In the reaction pyruvate + CoA + NAD+ → acetyl CoA + CO2 + NADH,

pyruvate is oxidized and NAD+ is reduced.

A protein's _____ structure contains helixes and sheets that result from hydrogen bonding between carboxyl and amino groups of the polypeptide chain.

secondary

The best way to describe cellular membranes is

semifluid with lipid rafts

The portion of an amino acid that makes it unique among the 20 different amino acids is its

side chain or R-group.

Diabetics can be given insulin that binds to receptors on cells throughout the body increasing glucose uptake. Insulin is an example of a

signal

The gonads produce steroids. The specific steroid-producing organelles in gonad cells are

smooth endoplasmic reticulum

If contents of the intestines can leak into the blood then ________ must have been damaged

tight junctions

The process that produces mRNA from DNA is called

transcription.