Unit 5 Lesson 9: Cellular respiration

Question 1

What does glucose intereact with during cellular respiration

Answer 1

At each step, glucose molecules interact with NAD+, FAD+, and other compounds, making different-sized carbon compounds and releasing energy.

Question 2

Cellular respiration breaks down the covalent bonds in sugar to do what

Answer 2

Cellular respiration breaks the covalent bonds in sugar molecules to make new bonds in the products, CO2 , H2O , and ATP.

Question 3

Cellular respiration breaks the covalent bonds in sugar molecules to make new bonds in the products, CO2
, H20 , and ATP. When is energy relased?

Answer 3

Because energy is stored in these bonds, it is only released when these bonds are broken

Question 4

Does breaking chemical bonds require enrgy

Answer 4

Energy is also needed to break chemical bonds.

Question 5

What does the cell need to get glycolysis started

Answer 5

In the human body, the cell needs a little spark of energy, from ATP, to get the glycolysis reactions started.

Question 6

It takes ? to break bonds, and ? is released when bonds are formed

Answer 6

energy

Question 7

Which one makes more energy the creation of the bonds in the pyruvic acids made by glycoylis or the breaking bonds in the glucose?

Answer 7

In the end, the creation of the bonds in the pyruvic acids made by glycolysis makes more energy than the breaking bonds in the glucose.

Question 8

How much ATP is needed to start glycolysis and how much atre made

Answer 8

During glycolysis 2 ATP molecules are used to start the reaction, but a total of 4 ATPs are made, making a net of 2 ATP molecules

Question 9

During glycolysis 2 ATP molecules are used to start the reaction, but a total of 4 ATPs are made, making a net of 2 ATP molecules. What is this kind of reaction called and why

Answer 9

This kind of reaction is called an exothermic reaction, because it makes more energy than it uses.

Question 10

What is the exact menaing of exothermic reaction

Answer 10

chemical reaction that results in heat given off as a product because the energy required to break bonds is less than the energy required to make new bonds

Question 11

Why arent ATP, FADH2, and NADH realiable enrgy courses depite containg lots of chemical energy

Answer 11

ATP, FADH2, and NADH have lots of chemical energy, but the molecules are not stable for long-term storage. An organism uses the energy available in ATP and NADH quickly.

Question 12

What happens when NAD+ and FAD+ pick up electrons and become NADH and FADH2

Answer 12

When NAD+ and FAD+ pick up electrons and become NADH and FADH2, they gain a hydrogen atom (or more

Question 13

What is it called When a reaction gains or loses electrons

Answer 13

When a reaction gains or loses electrons, it is called an oxidation-reduction (redox) reaction.

Question 13

What happens to NAD+ and FAD+ during the electron tranport chain

Answer 13

When they lose electrons at the electron transport chain, they also lose hydrogen atoms.

Question 14

What is an oxidation reaction

Answer 14

A reaction that loses electrons is an oxidation reaction

Question 14

What is the exact meaning of oxidation-reduction (redox) reaction

Answer 14

a chemical reaction that involves transferring electrons between two or more atoms

Question 15

What is a reduction reaction

Answer 15

A reaction that gains electrons is a reduction reaction because it becomes more negative (reduction in net charge).

Question 16

What does oxidized mean

Answer 16

So, oxidized means losing an electron and reduced means gaining an electron.

Question 17

What do atoms strive to have

Answer 17

Atoms strive to have no charge (neutral), but in nature atoms can have a net positive or net negative charge.

Question 18

How do atoms become neura

Answer 18

To become neutral atoms will either take or give away electrons.

Question 19

What does electrongative atoms want

Answer 19

Some atoms and molecules are electronegative, and want to gather electrons from negative ions as much as possible.

Question 20

electronegative

Answer 20

atoms and molecules that tend to acquire electrons in chemical reactions

Question 21

How do other atoms and molecules give up electrons

Answer 21

Other atoms and molecules give up electrons easily. It doesn’t take a lot of energy to break the bond.

Question 22

How much energy may be needed to break bond between electron and atom

Answer 22

It can take a lot of energy to break the bond between electron and atom.

Question 23

IS hydrogen electronegative compared to other compunds?

Answer 23

Hydrogen is usually less electronegative than the organic compounds, like carbon and oxygen, that it bonds to.

Question 24

What happens do hydrogens electons

Answer 24

So, those atoms and compounds will become reduced because they will bond to the hydrogen’s electrons.

Question 25

Is oxygen electronegative?

Answer 25

Oxygen is very electronegative, and it bonds to the electrons from other molecules tightly.

Question 26

Is water a stable or electrongetive

Answer 26

Water is a very stable compound.

Question 27

What makes oxygen to have a slightly negative charge and hydrogen to have a slightly positve

Answer 27

Oxygen pulls on electrons, keeping them closer to it than to the hydrogens to which those electrons came from. This makes the oxygen have a slightly negative charge, and the hydrogens slightly positive.

Question 28

How much water do molecules need to break aprt

Answer 28

Water molecules need a lot of energy to break apart.

Question 29

When do atoms have a higher energy level

Answer 29

In general, atoms have a higher energy level when they are bonded with atoms that are less electronegative, like hydrogen or carbon.

Question 30

When do atoms have a lower enrgy level

Answer 30

They have a lower energy level when they are bonded with atoms that are more electronegative, like oxygen.

Question 31

What happens when glucose is broken down

Answer 31

As glucose is broken down, it goes through a series of oxidation reactions. The product of each reaction has a lower energy level than the reactants. The carbons in glucose are bonded with many hydrogens, so glucose acts as a hydrogen and an electron donor. It can be oxidized.

Question 32

CO@ and electonrs

Answer 32

Carbon dioxide is not an electron donor—it is only bonded to oxygen. Oxygen in the glucose molecules will gain hydrogens, becoming reduced. So, the energy in glucose comes from the hydrogens, which easily break away from glucose to make water with the oxygen molecules.

Question 33

What happens when the bonds of a molece are broken

Answer 33

When the bonds of a molecule like glucose are broken, energy is released. Electrons move to a lower-energy level, as they move from glucose (reactant) to oxygen in the water and carbon dioxide (products), releasing its energy as it moves.

Question 34

what happens to elctons during electrong transport chain

Answer 34

As electrons move down the electron transport chain toward oxygen, their energy is released, and they have a lower energy level. The energy that is released is used to attach a phosphate group to ADP, making ATP.

Question 35

What are two reactants that are used in the process of cellular respiration?

Answer 35

oxygen and sugar

Question 36

Where does the energy come from to start the glycolysis process?

Answer 36

Glycolysis uses 2 ATPs to get the reactions started.

Question 37

Which of the following statements does NOT explain why energy is released during cellular respiration?

Electrons move from a high energy state to a lower energy state.
Hydrogens form strong bonds with oxygen.
Carbon forms strong bonds with oxygen.
ATP is converted to ADP.

Answer 37

ATP is converted to ADP.

Question 38

The energy of cellular respiration inputs is often ______ the outputs.

higher than
lower than
equal to
less important than

Answer 38

higher than

Question 39

Glucose is broken down in a series of ______.

Answer 39

oxidation reactions

Question 40

Why are the chemical bonds in glucose pretty easy to break (why do they require small amounts of energy to break)?

Answer 40

Hydrogen is usually less electronegative. When it forms bonds with carbon, these bonds contain a lot of energy. The carbons in glucose are connected to many hydrogens, so glucose acts as a hydrogen and an electron donor. The energy in glucose comes from the hydrogens, which easily break away from the glucose.

Question 41

Why are the bonds in water hard to break?

Answer 41

The oxygen in water is very electronegative, and it holds on to the hydrogens very tightly.

Question 42

Lactic acid fermentation can be modeled by this equation:

Answer 42

Pyruvic acid + NADH → Lactic acid + NAD+

Question 43

process of lactic fermentation

Answer 43

During lactic acid fermentation, glycolysis changes glucose into two pyruvic acids. This makes a net 2 ATPs and 2 NADHs. The next step is fermentation where the pyruvic acid molecules then use 2 NADHs to make two 3-carbon molecules of lactic acid. The NAD+s are sent back through glycolysis, where they are used to make more ATPs. The lactic acid is a byproduct of this process.

Question 44

purpose of lactic acid fermantaion

Answer 44

The purpose of lactic acid fermentation is to produce NAD+ that can be used to make more ATP. It results in short bursts of energy that usually last less than about 90 seconds. Lactic acid works to provide energy during anaerobic respiration because the body is not getting enough oxygen to undergo aerobic respiration. However, this process results in extra lactic acid that builds up in the muscles and blood causing a burning sensation in the muscle. After the sprint, the athlete will need to breathe heavily for several minutes, giving their body the extra oxygen needed to get rid of the lactic acid through other metabolic processes.

Question 45

Lactic acid fermentation of glucose makes

Answer 45

lactic acid and NAD+

Question 46

In the food industry, humans use microorganisms to make certain fermented foods, such as yogurt, sour cream, cheese, pickles, and sourdough bread.

Answer 46

Include the food item, microorganism name, how the food is made, and a description of the fermentation process.

In the first picture, cucumbers are used to make pickles through a process known as pickling. The cucumbers (or other vegetables) are covered in a brine solution. Within a day or so the lactobacillus bacteria (naturally living on the vegetables) begin to multiply and digest the sugars from the vegetables and make lactic acid.

In the second picture, a starter bacteria (usually from the Lactococcus, Lactobacillus, or Streptococcus families) is put into milk. The strain of bacteria is chosen depending on the type of cheese the maker wants to make. The bacteria ferment the milk sugar lactose to lactic acid.

Question 47

Fermentation of glucose by yeast produces

Answer 47

ethyl alcohol and carbon dioxide