biol chp. 2

Monomers

- single molecules that can be linked tighter to form larger molecules - simple sugars -nucleotides

The Miller-Urey experiment demonstrated that

. under specific conditions, the building blocks of life can be formed

Tertiary structure

3D structure

How do enzymes recognizer their substrates?

A binding site that fits the shape and complements the charge of the substrate

Which molecule is used as the primary source of chemical energy for tasks within a cell

ATP

Which of the choices are examples of coupled reactions

ATP hydrolysis drives sucrose synthesis from glucose and fructose, ATP synthesis is driven by a proton gradient formed in the mitochondria

What are the monomers, or building blocks of protein?

Amino acids

IMMUNITY

Antibodies recognize specific pathogens in the body

How does aspirin suppress the inflammation response?

Aspirin binds to the cyclooxyrgenase enzymes, preventing the synthesis of prostaglandins

Aerobic conditions

Citric acid cycle (Krebs cycle) Electron transport chain

TRANSPORT

Cytochromes are election carriers in the electron transport chain

Which of the following is NOT a carbohydrate?

D. Cholesterol

Replication: DNA ->

DNA

Identify hoe NAD+ is used by animal cells during anaerobic respiration

During fermentation, NAD+ is generated from NADH and is used to continue glycolysis

Which of the following statements about metabolic pathways is true?

Each pathway is regulated by specific enzymes.

The electron transport chain uses the transfer of _______ between protein complexes to set up a proton gradient

Electrons

Which statement about thermodynamics is true?

Entropy has a tendency to increase

Which of the statements best describes the overall role of enzymes in metabolism

Enzymes increase the speed of reactions

Endergonic

Generating carbohydrates in photosynthesis, pedaling a bike up a steep hill, constructing DNA from nucleotides

How do these two processes differently affect the metabolism of glucose?

Glucose is produced during photosynthesis to hold the energy gathered from light, whereas glucose is broken down during cellular respiration to release stored cellular energy

Which of the following cellular metabolic processes is active in all cells, regardless of the presence or the absence of oxygen?

Glycolysis

Glycogen

Highly branched, used for energy storage in mice

Which statements describe glycolysis?

It breaks down glucose to two pyruvate molecules It is common to aerobic and anaerobic respiration

What process do mulch cells use if oxygen is not available for aerobic respiration ?

Lactic acid fermentation Glycolysis

Arrange the steps that describe the flow of energy from sunlight to cellular work First step:

Light energy is given off by the sun Chloroplasts of primary producers absorb light energy Light energy, water, and CO2 are used to generate carbohydrates through photosynthesis Carbohydrates are broken down by organisms that consume,e the plant Breakdown of carbohydrates releases chemical energy that can power cellular work Last step

Starch

Moderately branched, used for energy storage in seeds

Compounds that enter the electron transport chain -> Compounds produced by the electron transport chain

NADH, FADH2, O2, ADP -> NAD+, FAD, H2O, ATP

DNA and RNA are nucleic acids. Like other polymers, nucleic acids are made up of repeating units called monomers. What are the monomers, or building blocks, of nucleic acids?

Nucleotides

Anabolic pathway

Photosynthesis generates storage carbohydrates CO2 and H2O, a lipid molecule is constructed from fatty acid subunits

Translation: RNA ->

Protein

Quaternary Structure

Protein-subunit

What product of glycolysis can be subsequently modified to enter the citric acid cycle under aerobic conditions?

Pyruvate

METABOLISM

Pyruvate kinase is a glycolysis enzyme that plays a role in breaking down glucose

RNA molecules that act as catalysts are called

Ribozymes

A plant cell synthesizes cellulose from glucose

Structural support

Choose DNA sequence complementary to AGTC

TCAG

What is a property of phospholipids that explains why lipids self-assemble into a bilayer

The hydrophilic heads of lipids are exposed to water at the membrane's surface

Why does the body use chemical energy?

The potential energy stored in chemical bonds can be released to preform work within a cell

Why does the passage of one glucose molecule through glycolysis have a payoff of only two ATP molecules?

Two ATP molecules are used in the initial phase of glycolysis, reducing the net gain to two ATP

Cellulose

Unbranched, Important for the structure of pine trees

DNA only

Uses thymine and is double stranded

Exergonic

a ball rolling down a hill, breaking down glucose in cellular respiration, metabolizing proteins into amino acids

In the disaccharide sucrose the monomers are held together by a/an

a-1,2 glycosidic linkage

All of the following are true EXCEPT

a. Aspirin is a reversible inhibitor of cyclooxygenase. b. Protein kinases can activate enzymes by adding phosphate groups. c. The binding of an allosteric activator stabilizes the active form of an allosteric enzyme. d. The cancer drug, methotrexate, is an example of a competitive inhibitor. (correct answer is A)

Which of the following statements about ATP is FALSE?

a. The synthesis of ATP is an exergonic reaction.

Not essential for life

abundant and varied food sources, volcanic vents, low levels of carbon dioxide, radiation levels greater than a nuclear explosion

Outputs

amino acids, hydrocarbons

choose the best definition for activation energy

amount of energy required to initiate a chemical reaction

The phospholipid bilayer membrane structure forms in water because the individual phospholipids...

are amphipathic

Retroviruses, such as HIV, have an enzyme that allows them to catalyze DNA synthesis from an RNA template. This evidence supports the hypothesis that

b) early life consisted of an "RNA world."

An inhibitor that binds noncovalently to the active site is ___ while an inhibitor that binds noncovalently to a different site is _____. Both types of inhibition are ____

competitive, noncompetitive, reversible

Breakdown of glucose to pyruvate

cytosol

In an enzyme-catalyzed reaction,

e. The ΔG between reactants and products is not changed.

Lipids are ________

e. insoluble in water

Which stage directly generate the greatest number of ATP molecules per metabolized glucose molecule

electron transport chain and ATP synthase

Anaerobic conditions

fermenation

the nucleotide base that complements cytosine is

guanine

What intermolecular force is responsible for holding the two stranded of a DNA double helix together

hydrogen bond

which process is used to break down polymers into monomers

hydrolysis

Which statements describe a catalyst

increases the rate of endergonic reactions, lowers the activation energy of a chemical reaction, is not consumed during the chemical reaction

DNA

is a single molecule that can be over 10,000,000 nucleotides long, is the genome for eukaryotic organisms, is usually double stranded, includes the base thymine

what is the significance of a lower activation energy

it increases the rate of cellular reaction

STRUCTURAL

keratins are fibrous proteins that are components of skin and hair.

AEROBIC

oxygen as final electron acceptor high levels of ATP produced Oxygen required acetyl CoA production Complete combustion of glucose

Which of the statements regarding potential energy is true

potential energy is the energy that an object has based on its position

ANEROBIC

small organic compounds as final electron acceptor low levels of ATP produced oxygen not required fermentation oxygen toxicity ethanol production

How does the second law of thermodynamics apply to this process

some energy does work and some energy escapes as thermal energy when the energy in ATP is released from the chemical bond

The ATP made during glycolysis is generated by

substrate-level phosphorylation

Product

the small chains of simple sugars

Enzyme

the specialized protein

Substrate

the starch molecules

Where should the drug bind to competitively inhibit the enzyme?

to the active site of the enzyme

Pyruvate is a product of glycolysis and is subsequently converted to acetyl-CoA. Acetyl-CoA is a substrate for the citric acid cycle (CAC) Exactly how many molecules of glucose must be oxidized in glycolysis to provide the input for four turns of the CAC?

two

Polymers

- molecules composed of smaller sub units linked together -starch - muscle protein - RNA

a helices

-coil- like structure around a central axis -form lond, thin structures important for transmembrane proteins

How does dehydration reaction differ from a hydrolysis reaction

-dehydration removes a water molecule and hydrolysis adds a water molecule -polymers break into monomers in hydrolysis and monomers join together in dehydration

B sheets

-keep their shape due to hydrogen bonds between adjacent polypeptide chains - flat, zig-zag-like structure

What is a phosphodiester bond

A covalent bond that forms the backbone of DNA and RNA molecules

what is the proton gradient in cellular respiration?

A higher concentration of protons (H+) on one side of a membrane than the other

Arrange the steps of ATP generation by ATP synthase in the order that they occur First step

A hydrogen ion gradient is established between the inter membrane space and the mitochondrial matrix hydrogen ions move down their gradient through a channel in ATP synthase Hydrogen ions cause the rotor portion of ATP synthase to spin Catalytic sites in the knob portion of ATP synthase phosphorylate ADP Last step

Which statement is an example of the chemical potential energy in adenosine triphosphate (ATP) being turned into work

A phosphate group is transferred from ATP to glucose during glycolysis, ATP hydrolysis induces a conformational change in a protein that moves ions across a membrane

How do enzymes lower the activation energy of a reaction?

By stressing a bond in a substrate that needs to be broken, by forming a temporary bond between the active site and the substrate, by producing conditions within the active site conducive to the reaction

Which equation is the simplified chemical equation for cellular respiration?

C 6 H 12 0 6 + 6 0 2 -> 6 H 2 O +6 C O 2

Which is the molecular formula for carbohydrate

C4H8O4

A liver cell synthesizes glycogen from glucose

Energy storage

Which of the environment factors listed can cause denaturation?

Extreme pH, excessive heat

A proton gradient is formed in the mitochondria such that the concentration of proton (H+) is higher on one side of the inner mitochondrial membrane than on the other side What is the purpose of this proton gradient?

Generated ATP in the electron transport chain

Which of the statements is a simplified equation for cellular respiration? Glucose + Oxygen -> Carbon dioxide + water Glucose + nitrogen -> Carbon monoxide + water Carbon dioxide + water + light -> glucose + oxygen Protein + water -> amino acids + carbon dioxide

Glucose + oxygen -> carbon dioxide + water

Catabolic pathwy

Glycolysis converts one molecule of glucose to two molecules of pyruvate, A protein molecule is broken down into amino acid subunits

Which describes how cofactors and coenzymes affect the function of enzymes? Decrease catalytic function Increase catalytic function increase or decrease catalytic function Do not impact catalytic function

Increase catalytic function

What is the function of the proton gradient in the mitochondrion?

It is potential energy that the cell uses to generate ATP

Why is cellular respiration referred to as an aerobic process?

It requires oxygen to occur

Reduction

Loss of Oxygen gain of electrons gain of hydrogen decrease in the number of carbon-oxygen bonds

Oxidation

Loss of electrons loss of hydrogen increase in the number of carbon-oxygen bonds gain of oxygen

A heart cell uses the energy in glucose to synthesize ATP

Metabolism for energy

Conversion of pyruvate to acetyl-CoA

Mitochondrial matrix

SIGNALING

Mitogen-activated protein (MAP0 kinases direct a cell's response to stimuli, such as osmotic stress

During glycolysis, glucose is broken down into two molecules of pyretic acid. How many carbon atoms are in each pyruvic acid molecule?

Number of carbon atoms: 3

Transcription: DNA ->

RNA

How do organisms use energy, according to the first law of thermodynamics

The light energy collected during photosynthesis is converted to chemical energy , animals eat to obtain chemical energy that they convert into kinetic energy

Choose all the true statements about oxidative phosphorylation

The oxidation of NADH provides enough energy to produce three ATP molecules During oxidative phosphorylation, the proton motive force created by the electron transport chain drives the production of ATP Oxidative phosphorylation is an aerobic process

Feedback inhibition is important for the regulation of Manu metabolic pathways. Which of the statements are examples of feedback inhibition?

The production of tryptophan is halted by the presence of excess tryptophan The beginning of glycolysis is inhibited. by high levels of ATP

Which definition describes enthalpy

a measure of the amount of internal energy in a system at constant pressure

Which of the statements best describes a protocol

a membranous sac containing organic molecules that interact with one another

which statements describe a chemical reaction

a molecule breaks apart, an acid is neutralized by a base

Which of these describes an anabolic pathway

a pathway that generates molecules from smaller subunits

What is a statement that describes a gene

a section of DNA in which the code for a protein is located

The role of oxygen gas in our cells is to

accept electrons from the respiratory chain

the nucleotide base that complements thymine is

adenine

A ribozyme is

an RNA catalyst

The "backbone" of a nucleic acid molecule is made of

b. alternating sugar and phosphate groups

Consider the following double-stranded DNA region: 5′ -TGCCAT-3′ 3′ -ACGGTA-5′ If the lower strand is transcribed, which of the following strands will result?

c. UGCCAU

What would happen to the value of ∆G for the reaction in which phosphoenolpyruvate is converted to pyruvate (∆G = -23 kJ/mol) when it reaches equilibrium?

d. ∆G would equal 0.

When cells link monomers together to construct polymers, which process is used to make the monomers form bonds with each other?

dehydration

the active site of an enzyme

determines, by its structure, the specificity of the enzyme

What is the share of DNA molecules

double helical

What is the shape of DNA molecules?

double helictal

when do amino acids that have had their amine groups removed enter the pathways of cellular respiration?

during glycolysis or during the Krebs cycle

Choose from the list below the correct numbers of ATP molecules released per glucose molecule by glycolysis (gly), the citric acid cycle (CAC), and oxidative phosporylation (OP)

gly 2 (net); CAC 2; OP 28

Both Aerobic and Anaerobic conditions

glycolysis

If ΔG of a chemical reaction is negative and the change in entropy is positive, you can conclude that the reaction

is exergonic

RNA

is usually single stranded, includes ribose sugar, can be translated into protein, is a single molecule that can form a complex secondary structure

Essential for life

liquid water, sunlight, chemical reaction, or geologic heat providing energy, atoms and molecules from which to build living cells

Secondary structure

local hydrogen-bond pattern

which characteristics of ribozymes provide support for the RNA world hypothesis

made of RNA, involved in protein synthesis, are catalysts

Both RNA and DNA

made of nucleotides, Fontaine's codes for proteins

citric acid cycle

mitochondrial matrix

the majority of ATP is generated

mitochondrial membrane

Compared to fermentation, the aerobic pathways of glucose metabolism produce

more ATP

DNA and RNA are nucleic acids. Like other polymers, nucleic acids are made up of repeating units called monomers

nucleotides

DNA and RNA are nucleic acids. Like other polymers, nucleic acids are made up of repeating units called monomers. What are the monomers, or building blocks, of nucleic acids?

nucleotides

Most of the ATP produced during cellular respiration comes from

oxidative phosphorylation

The oxidation of malate to oxaloacetate is coupled to the reduction of NAD+ to NADH + H+. In this process, NAD+ is a(n)

oxidizing agent

Which statement describes a functional group?

part of a larger molecule that can participate in a chemical reaction

Primary structure

polypeptide chain

Anabolic reactions

require an input of energy

Cheese, which is a solid at room temperature, is often used in cooking

saturated

Coconut oil, which is a solid at room temperature, can be used as an alternative to butter

saturated

Which substances contain, or are examples of , lipids

testosterone, beeswax, cell membrane

What describes a genome

the collection of genetic material in a cell or organism

choose the best description of kinetic energy

the energy an object has due to its motion

How does adenosine triphosphate (ATP) drive energy-required reactions in the cell

the hydrolysis of ATP is coupled to a non-spontaneous reaction

which statement explains the appearance of a three-layer membrane in micrographs

the hydrophilic heads of the bilayer show up as two dense layers, whereas the hydrophobic tails show up as a single, lighter layer

Olive oil, which is a liquid at room temperature, is used in cooking pasta

unsaturated

The oil inside fish oil supplements is fluid at room temperature

unsaturated

all of the following nitrogenous bases are found in DNA except

uracil

which statement best describes free energy

useful energy, associated with a reaction, that can perform work

RNA only

uses uracil, single stranded

Inputs

water, ammonia, hydrogen gas