Biology 101 Exam #2 (Cellular Respiration, CH6)

For each glucose that enters glycolysis, _____ NADH enter the electron transport chain.

10

Which statement describes glycolysis? A: This process produces some ATP and carbon dioxide in the mitochondrion. B: This process joins 2 pyruvic acid molecules into a molecule of glucose. C: This process splits glucose in half and produces 2 ATPs for each glucose. D: This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. E: This process converts pyruvic acid to acetyl CoA.

C: This process splits glucose in half and produces 2 ATPs for each glucose.

During electron transport, energy from _____ is used to pump hydrogen ions into the _____. A: NADH and FADH2 ... mitochondrial matrix B: NADH ... mitochondrial matrix C: NADH ... intermembrane space D: acetyl CoA ... intermembrane space E: NADH and FADH2 ... intermembrane space

E: NADH and FADH2 ... intermembrane space

If you exceed your aerobic capacity during a workout, your muscle cells will __________.

Switch to anaerobic respiration and produce lactic acid. Even when oxygen supply is low, muscles cells can obtain a little energy through the conversion of glucose to lactic acid via anaerobic respiration.

In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain? nucleus mitochondrion lysosome chloroplast Golgi apparatus

mitochondrion

What is the name of the process in which pyruvic acid is converted to lactic acid? A: aerobic respiration B: aerobic metabolism C: reduction reaction D: glycolysis E: fermentation

E: fermentation During lactic acid fermentation, pyruvic acid is reduced directly by NADH to form lactic acid.

In electron transport, high-energy electrons "fall" to oxygen through a series of reactions. The energy released is used to _____.

Transport protons into the intermembrane space of the mitochondria, where they become concentrated. They then flow back out into the the inner compartment (matrix) of the mitochodria. On the way back, protons turn ATP synthase turbines and produce ATP.

In glycolysis there is a net gain of _____ ATP.

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Which statement describes the electron transport chain? A: This process splits glucose in half and produces 2 ATPs for each glucose. B: This process produces some ATP and carbon dioxide in the mitochondrion. C: This process converts pyruvic acid to acetyl CoA. D: This process joins 2 pyruvic acid molecules into a molecule of glucose. E: This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration

E: This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. In the electron transport chain, electrons move from one electron carrier to another, eventually reaching oxygen. The released energy is used to make ATPs.

Which of these is NOT a product of the citric acid cycle (also called the Krebs cycle)?

A: acetyl CoA (it enters the Krebs cycle)

What must pyruvic acid be converted to before it can enter the citric acid cycle? A: ethyl alcohol B: citric acid C: acetyl CoA D: lactic acid

C: acetyl CoA

What is the role of oxygen in cellular respiration? A: Oxygen provides electrons for transfer to glucose B: Oxygen accepts electrons after they are stripped from glucose C: Oxygen is required to convert ADP to ATP D: Oxygen is involved in the initial breakdown of glucose to pyruvic acid

B: Oxygen accepts electrons after they are stripped from glucose Need help? http://media.pearsoncmg.com/bc/bc_0media_bio/mp3tutors/h/Cell2.html?5&Cell2

Which of these enters the citric acid cycle (also called the Krebs cycle)? A: NADH + H+ B: acetyl CoA C: G3P D: glucose E: pyruvate

B: acetyl CoA Acetyl CoA is a reactant in the citric acid cycle.

The final electron acceptor of cellular respiration is _____. A: water B: oxygen C: FADH2 D: NADH E: CO2

B: oxygen Oxygen is combined with electrons and hydrogen to form water.

For each glucose that is broken down by aerobic respiration, ____ NADH enter the electron transport chain. A: 4 B: 2 C: 0 D: 10

D: 10 For each glucose molecule that enters glycolosis, a total of 10 NADH are produced -- 2 are produced in glycolysis, 2 are produced in acetyl CoA production, and 6 are produced in the citric acid cycle. Need help? https://mediaplayer.pearsoncmg.com/assets/secs-campbell-electron-transport

An abundant and continual supply of ATP is necessary for all living cells. Active muscle cells require an extraordinary amount of ATP to permit strenuous exercise for prolonged periods. Toxins, reduced blood flow, and a compromised respiratory system can interfere with the transport of oxygen to active cells. A runner in a marathon faces multiple obstacles to continue to produce sufficient ATP to remain competitive. Breathing faster when we exercise is necessary to expel ________.

D: carbon dioxide and bring in more oxygen to support aerobic metabolism

Which of the following processes takes place in the cytosol of a eukaryotic cell? A: electron transport chain B: citric acid cycle C: ATP production by ATP synthase D: glycolysis E: acetyl CoA formation

D: glycolysis Glycolysis, the breakdown of glucose into two molecules of pyruvic acid, takes place in the cytosol, outside the mitochondria.

Which of these stages occur(s) in the cytoplasm? A: glycolysis B: citric acid cycle and electron transport C: glycolysis and citric acid cycle D: citric acid cycle

A: glycolysis

A process is referred to as aerobic if it requires _______. A: oxygen B: carbon dioxide C: ATP D: carbohydrates

A: oxygen

How many NADH are produced by glycolysis?

2 NADH are produced by glycolysis.

A glucose molecule is completely broken down upon completion of glycolysis and the citric acid cycle. However, these two processes yield only a few ATPs. What other energy carrier(s) that can be used to synthesize more ATPS is/are also generated during these processes? A: oxygen used in the electron transport chain B: NADH and FADH2 C: heat D: FAD and NAD+

B: NADH and FADH2 The energy in NADH and FADH2 is used to drive the synthesis of many ATP molecules in the electron transport chain. In glycolysis, glucose is split into two molecules of pyruvic acid. The released energy is stored in ATP and the electron carrier NADH.

An important end product of cellular respiration is __________. A: hydrogen gas B: water C: glucose D: pyruvic acid E: ATP

B: water Water, carbon dioxide, and energy are the end products of cellular respiration.

The waste products of cellular respiration include ________. A: water only B: water and carbon dioxide C: carbon dioxide only D: water and glucose

B: water and carbon dioxide

A glucose molecule is completely broken down upon completion of glycolysis and the citric acid cycle. However, these two processes yield only a few ATPs. What other energy carrier(s) that can be used to synthesize more ATPS is/are also generated during these processes? A: FAD and NAD+ B: heat C: NADH and FADH2 D: oxygen used in the electron transport chain E: NADH and NAD+

C: NADH and FADH2

Which of these equations describes aerobic cellular respiration? A: glucose → lactic acid + energy B: energy + carbon dioxide + water → glucose + oxygen + water C: glucose + oxygen → carbon dioxide + water + energy D: none of the above

C: glucose + oxygen → carbon dioxide + water + energy

Which of the following metabolic pathways is common to both aerobic and anaerobic processes of sugar breakdown? A: conversion of pyruvic acid to lactic acid B: the electron transport chain C: glycolysis D: the citric acid cycle

C: glycolysis

In cellular respiration, most ATP molecules are produced by ______. A: substrate-level phosphorylation B: cellular respiration C: photosynthesis D: oxidative phosphorylation E: photophosphorylation

D: oxidative phosphorylation This process utilizes energy released by electron transport.

What compound directly provides energy for cellular work? A: fat B: glucose C: C6H12O6 D: ATP

D: ATP

Which of these is NOT a product of glycolysis? A: NADH + H+ B: water C: ATP D: FADH2 E: pyruvate

D: FADH2

Which part of cellular respiration produced the most NADH? A: fermentation B: electron transport chain C: glycolysis D: citric acid cycle

D: citric acid cycle

In glycolysis, ATP molecules are produced by _____. A: substrate-level phosphorylation B: photophosphorylation C: cellular respiration D: oxidative phosphorylation E: photosynthesis

A: substrate-level phosphorylation

What is the correct general equation for cellular respiration? A: 6 CO2 + 6 H2O + ATP energy → C6H12O6 + 6 O2 B: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP energy C: C6H12O6 + 6 CO2 → 6 O2 + 6 H2O + ATP energy D: 6 O2 + 6 H2O + ATP energy → C6H12O6 + 6 CO2 E: C6H12O6 + 6 H2O → 6 CO2 + 6 O2 + ATP energy

B: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP energy Cellular respiration extracts energy from glucose (C6H12O6) to produce smaller energy packets (ATP).

The electron transport chain is a series of electron carrier molecules. Where are these molecules located in eukaryotic cells? A: the plasma membrane B: the inner membrane of the mitochondria C: the smooth endoplasmic reticulum D: the rough endoplasmic reticulum E: the cytoplasm

B: the inner membrane of the mitochondria Electron carrier molecules work by coupling electron transfer between electron donors and acceptors (such as NADH and O2) with the transfer of H+ ions across the inner mitochondrial membrane.

The main function of cellular respiration is __________. A: breaking down toxic molecules B: making food C: making ATP to power cell activities D: producing cell structures from chemical building blocks E: producing oxygen

C: making ATP to power cell activities The energy made available during cellular respiration is coupled to a process that adds a phosphate group to ADP, making ATP.

Glycolysis occurs in almost all organisms on Earth. From this we might conclude that __________. A: glycolysis is the most efficient energy-producing process in living cells B: glycolysis evolved because plants produce glucose C: glycolysis first evolved in the presence of oxygen D: glycolysis evolved very early in ancestors that are common to all the domains of life

D: glycolysis evolved very early in ancestors that are common to all the domains of life

In glycolysis, what starts the process of glucose breakdown? A: ADP B: Pyruvate C: NADPH D: FADH2 E: ATP

E: ATP

In muscle cells, fermentation produces _____. A: carbon dioxide, ethanol, NAD+, and ATP B: carbon dioxide, ethanol, NADH, and ATP C: pyruvate D: lactate and NADH E: lactate and NAD+

E: lactate and NAD+

Which part(s) of cellular respiration take(s) place in the mitochondria? A: the electron transport chain B: glycolysis C: the Citric Acid cycle D: the Citric Acid cycle and the electron transport chain E: All of the above

D: the Citric Acid cycle and the electron transport chain

NADH and FADH 2 are important in cellular respiration because they deliver high-energy electrons to the electron transport system. Electron transport produces _____ ATP molecule(s) per NADH molecule and _____ ATP molecules(s) perFADH 2 molecule. A: three... two B: two... three C: one... one D: zero... zero E: two... zero

A: three... two

In the absence of oxygen the net gain of ATP for each glucose molecule during glycolysis is approximately __________. A: 2 ATPs B: 4 ATPs C: 6 ATPs D: 38 ATPs E: nothing, because all the electrons are associated with lactic acid

A: 2 ATPs

Compare Oxidation and Reduction Reactions: A: Which gains electrons? B: What kinds of molecules have more energy? R'd or O'd? C: Which kinds of molecules have more Hydrogen? R'd or O'd? D: What is the combination of these two reactions called? In other words, what kind of reaction has these two occur simultaneously.

A: Reduction reactions gain electrons. B: Reduced molecules have more energy than oxidized ones. C: Reduced molecules are concentrated in H and are reduced. For example, fats take a lot of energy. D: Redox reaction.

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 contain large amounts of lactic acid following even mild physical exercise B: the muscle cells cannot split glucose to pyruvic acid C: the muscles require extremely high levels of oxygen to function D: the muscles contain large amounts of carbon dioxide following even mild physical exercise

A: the muscles contain large amounts of lactic acid following even mild physical exercise

The proximate (immediate) source of energy for oxidative phosphorylation is _____. A: ATP B: NADH and FADH2 C: ATP synthase D: kinetic energy that is released as hydrogen ions diffuse down their concentration gradient E: substrate-level phosphorylation

D: kinetic energy that is released as hydrogen ions diffuse down their concentration gradient

In the citric acid cycle (also called the Krebs cycle), ATP molecules are produced by _____.

D: substrate-level phosphorylation A phosphate group is transferred from GTP to ADP. Need help? https://mediaplayer.pearsoncmg.com/assets/secs-campbell-citricacid-cycle

Which statement describes the citric acid cycle? A: This process splits glucose in half and produces 2 ATPs for each glucose. B: This process joins 2 pyruvic acid molecules into a molecule of glucose. C: This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. D: This process converts pyruvic acid to acetyl CoA. E: This process produces some ATP and carbon dioxide in the mitochondrion.

E: This process produces some ATP and carbon dioxide in the mitochondrion. The citric acid cycle breaks down carbon molecules, releasing carbon dioxide and forming some ATP.

Chemical reactions that require oxygen are called _____ while those that do not require oxygen are considered _____. A: anaerobic ... aerobic B: aerobic ... fermentation C: fermenters ... aerobic D: producers ... consumers E: aerobic ... anaerobic

E: aerobic ... anaerobic

Select the correct sequence of steps as energy is extracted from glucose during cellular respiration. A: glycolysis → citric acid cycle → acetyl CoA → electron transport chain B: citric acid cycle → electron transport chain → glycolysis → acetyl CoA C: electron transport chain → citric acid cycle → glycolysis → acetyl CoA D: acetyl CoA → citric acid cycle → electron transport chain → glycolysis E: glycolysis → acetyl CoA → citric acid cycle → electron transport chain

E: glycolysis → acetyl CoA → citric acid cycle → electron transport chain Glycolysis produces pyruvic acid, which enters the mitochondrion. There, it is converted to acetyl CoA, which enters the citric acid cycle. Electron carriers bring electrons from the first three steps to the electron transport chain, and ATP is made.