Chapter 9 Biology Test Study

cellular respiration

if oxygen is available, organisms can obtain energy from food by this process

aerobic

pathways of cellular respiration that require oxygen ("in air")

anaerobic

pathways of cellular respiration that do not require oxygen ("without air")

glycolysis

the first set of reactions in cellular respiration

NAD+

one of the reactions of glycolysis removes 4 electrons, now in a high-energy state, and passes them to this electron carrier (nicotinamide adenine dinucleotide)

Krebs cycle

the second stage of cellular respiration

matrix

the innermost compartment of the mitochondrion and the site of the Krebs cycle reactions

Fermentation

When oxygen is not present, glycolysis is followed by a pathway that makes it possible to continue to produce ATP without oxygen, and the combined process of this pathway is called this

What happens during Glycolysis?

Glucose breaks down into two molecules of pyruvate

What combines with Acetyl Coa to form Citric Acid?

a 4-carbon molecule or pyruvic acid

What are the 3 stages of Cellular Respiration and where do they occur?

Glycolysis, the Krebs cycle, and the Electron Transport Chain. Glycolysis occurs in the cytosol, the Krebs cycle occurs in the matrix of the mitochondria, and the Electron Transport Chain occurs in the inner mitochondrial membrane of the mitochondria

What compound is used to extract energy from during the Kreb's cycle?

pyruvic acid produced in glycolysis is broken down into carbon dioxide in a series of energy-extracting reactions

Does Glycolysis require energy and why?

Glycolysis does require energy to break apart from glucose to form pyruvic acid

What is the function of NAD+?

NAD+ accepts a pair of high-energy electrons and become NADH

What is the goal of Cellular Respiration as compared to Photosynthesis?

The goal is to make ATP

What are the products of each stage of Cellular Respiration?

Glycolysis produces 4 ATP, 2 Pyruvic Acid, and 2 NADH. The Krebs cycle produces 2 ATP, 6 NADH, 2 FADH2, and 4 CO2. The Electron Transport Chain produces 32 ATP and H2O

How many ATP are made at each step of Cellular Respiration?

Glycolysis produces 4 ATP, the Krebs cycle produces 2 ATP, and the Electron Transport Chain produces 32 ATP

Which of the following is the correct sequence of events in cellular respiration?

glycolysis ? Krebs cycle ? electron transport chain

Which of these is a product of cellular respiration?

water

Which process does NOT release energy from glucose?

photosynthesis

Unlike photosynthesis, cellular respiration occurs in

all eukaryotic cells

The starting molecule for glycolysis is

glucose

Which of the following is NOT a product of glycolysis?

glucose

The Krebs cycle does NOT occur if

oxygen is not present

The Krebs cycle produces

carbon dioxide

In eukaryotes, electron transport occurs in the

inner mitochondrial membrane

Which of the following is NOT a stage of cellular respiration?

fermentation

Cellular respiration is called an aerobic process because it requires

oxygen

Photosynthesis is to chloroplasts as cellular respiration is to

mitochondria

The products of photosynthesis are the

reactants of cellular respiration

Glycolysis provides a cell with a net gain of

2 ATP molecules

Glycolysis requires

ATP

The Krebs cycle starts with

pyruvic acid and yields carbon dioxide

Which of the following pass high-energy electrons to the electron transport chain?

NADH and FADH2

Cellular respiration uses 1 molecule of glucose to produce approximately

36 ATP molecules

Lactic acid fermentation occurs in

muscle cells

During fermentation,

NAD+ is regenerated, allowing glycolysis to continue

Breathing heavily after running a race is your body's way of

repaying an oxygen debt

The energy needed to win a 1-minute footrace is produced mostly by

lactic acid fermentation

Photosynthesis occurs only in plants, algae, and some bacteria. In contrast, _________ occurs in all eukaryotic cells.

cellular respiration

Glycolysis rearranges a 6-carbon glucose molecule into 3-carbon molecules of __________

pyruvic acid

When ___________ pass through ATP synthase, ATP molecules are produced from ADP molecules

H+ ions

Glycolysis alone nets only ____ molecules of ATP from each glucose molecule

2

The body gets rid of lactic acid in a chemical pathway that requires __________

oxygen

Why does lactic acid fermentation "kick in" during a sprint race?

to get the ATP it needs to help out the body and help breathe

Alcoholic Fermentation

carried out by yeast; produces alcohol; produces carbon dioxide

Lactic acid Fermentation

carried out in muscle cells; produces lactic acid

Alcoholic Fermentation and Lactic acid Fermentation

begin with pyruvic acid; convert NADH to NAD+; do not require oxygen; occur in the cytoplasm; release energy

Alcoholic fermentation is used to make which product?

bread

What kind of taste do lactic acid bacteria give foods?

sour

What are some milk products made from lactic acid fermentation?

sour cream, yogurt, and cheese

What is one main different between fermentation and aerobic respiration?

Fermentation is anaerobic, so it takes place without oxygen. Aerobic respiration takes place with oxygen.

At what time does the runner's body switch from energy supplied by lactic acid to energy supplied by cellular respiration?

90 seconds

What process gives a runner more energy?

cellular respiration

You are in a race that lasts 25 minutes. Where will your body get the energy it needs?

breakdown of fats

Compare the ATP production of a sprinter and that of a long-distance runner.

A sprinter's muscle cells produce most of their ATP by lactic acid fermentation, which can last about 90 seconds. For the long-distance runner, cellular respiration is the only way to supply enough ATP. Cellular respiration releases energy more slowly and

aerobic step in cellular respiration

Krebs cycle

an energy molecule with three phosphate groups

ATP

anaerobic step of cellular respiration in which glucose is split

glycolysis

Alcoholic fermentation produces both ethyl alcohol and _________

carbon dioxide

Which process releases energy from food in the presence of oxygen?

cellular respiration

Why do most organisms undergo the process of cellular respiration?

The process of cellular respiration takes place in stages. During cellular respiration, cells trap bits of chemical energy and use them to make ATP.

How do cells release energy from food in the presence of oxygen?

Glycolysis does not require oxygen but the Krebs cycle and electron transport chain do require oxygen. Oxygen serves as the final electron acceptor of the electron transport chain, during which the majority of ATP is produced.

How do cells release energy from food without oxygen?

When oxygen is not present, glycolysis is followed by a pathway that continues the production of ATP. This pathway plus glycolysis is called fermentation. Fermentation releases energy from food molecules by producing ATP.

The calorie used on food labels is equal to

1000 calories

Calorie is also referred to as a

kilocalorie

Cells use the energy stored in chemical bonds of foods to produce compounds that directly power the cell's activities such as

ATP

The equation that summarizes cellular respiration using chemical formulas is

6O2 + C6H12O6 -> 6CO2 + 6H2O + Energy

If cellular respiration took place in just one step, most of the ________ would be lost in the form of light and ________

energy, heat

Cellular respiration begins with a pathway called _________, which takes place in the ________ of the cell.

glycolysis, cytoplasm

At the end of glycolysis about _____ percent of the chemical energy is locked in the bonds of the ________ molecule

90, pyruvic acid

Cellular respiration continues in the _______ of the cell with the _______ and electron transport chain

mitochondria, Krebs cycle

The pathways of cellular respiration that require oxygen are said to be _______. Pathways that do not require oxygen are said to be _________

aerobic, anaerobic

The energy flow in photosynthesis and cellular respiration occurs in the ______ direction

opposite

Photosynthesis ______ energy in Earth's "savings account" for living organisms

deposits

Cellular respiration removes _______ from the air

oxygen