Olson, Cell Physiology

Front 1

What is Glycogen?

Back 1

- A source of stored glucose within the cell
- Glucose is used immediately or stored as glycogen

Front 2

What is Glycogenesis?

Back 2

- The process of glycogen formation.
- Also called Anabolism
- Glucose, lactic acid, pyruvic acid, and some amino acids can be converted to glycogen. Occus in liver and muscles

Front 3

What is Glycogenolysis?

Back 3

- The breakdown of stored glycogen to reform glucose, occurs with low blood glucose levels.
- It is split by phosphorylation (an enzyme that is activated by epi or glucagon when needed)
- Catabolism

Front 4

What is Oxidation?

Back 4

- The removal and transfer of electon pair
- Carbohydrates, fats, proteins are oxidized in the cell to produce energy.
- Glycolysis produces a net of two molecules of ATP per glucose through this process.
- The process is often called Oxidative Cellular metabolism

Front 5

What is the process of transfering energy from carbs, fats, and proteins to ATP in the mitochondria called?

Back 5

Oxidative Phosphorylation.
- This reaction requires a coenzyme such as NAD (nicotinamide adenine dinucleotide)
- occurs in mitochondria

Front 6

What is the role of ATP?

Back 6

ATP (adenosine triphosphate) is found in the cytoplasm and nucleoplasm of all cells.
- ATP is used by the cell for muscle contraction and active transport of molecules across cellular membranes. The function is not only to store energy but also to transfer it from one molecule to another.

Front 7

How is ATP formed?

Back 7

By the process of splitting (lysis) of gucose molecules (glycolysis). 2 ATP molecules are produced per glucose molecule through oxidation.

Front 8

How many net molecules of ATP are gained with glycolysis?

Back 8

2

Front 9

If glucose is needed immediately upon entering the cells to supply energy, what metabolic process begins?

Back 9

Glycoysis (catabolism)

Front 10

What three things can be oxidized in a cell to produce energy (ATP)?

Back 10

Fats, Proteins, and Carbohydrates

Front 11

Where is ATP found?

Back 11

In cytoplasm and nucleoplasm of all cells.

Front 12

Your blood sugar concentration is controlled by what three hormones?

Back 12

Insulin
Glucagon
Epinephrine

Front 13

What is the end product of glycolysis?

Back 13

ATP and Pyruvic acid.
- little ATP is released, but further reactions convert pyruvic acid to acetyl CoA which is then converted to citric acid during the citric acid cycle, then to ATP.

Front 14

What is gluconeogenesis?

Back 14

The process of converting pyruvic acid back to glucose.

Front 15

What is the electron transport chain?

Back 15

- During oxidative phosphorylation electrons are removed from H atoms to form hydrogen ions. These electrons enter an electron transport chain.
- During the transport of these electrons energy is released that is used to cause the synthesis of ATP.
- Electrons eventually combine with oxygen & hydrogen to form water
- 30 ATP molecules formed

Front 16

How is glucose in the blood stream transported into the cell?

Back 16

Through facilitated diffusion, the MW of glucose is to great for passive diffusion.
- transport is from higher concentration to lower concentration
- insulin increases rate of transport into cell

Front 17

What is the first step in carbohydrate metabolism?

Back 17

Glycolysis - simple sugars are broken down into pyruvate by an anaerobic process.
- requires 2 ATP molecules

Front 18

How many ATP molecules are needed for glycolysis?

Back 18

2

Front 19

What does the citric acid cycle (Kreb's cycle) begin and end with?

Back 19

4 carbon molecule called oxalacetate

Front 20

How many total molecules of ATP are formed from one molecule?

Back 20

38 molecules

Front 21

Where does Anaerobic glycolysis occur?

Back 21

cell cytoplasm (not mitochondria)

Front 22

What occurs when glycogen cells are full (enough to supply 12-24 hrs of energy)?

Back 22

Glycogen is converted to fat in the liver and fat cells where it's stored as fat.

Front 23

What does the rate of gluconeogenesis depend on?

Back 23

decreased carbs and blood sugar.

Front 24

Lipids are mostly composed of what?

Back 24

fatty acids
- cholesterol doesnt contain fatty acids but similar

Front 25

The formation of glucose from amino acids (proteins) and glycerol (fats) is termed what?

Back 25

Gluconeogenesis
- 60% of amino acids can be converted to glucose

Front 26

Name the three most important lipids

Back 26

Triglycerides (neutral fat)
Phospholipids
Cholesterol

Front 27

What is the first step in using triglycerides for energy?

Back 27

Their hydrolysis into fatty acids and glycerol. They are then transported in the blood to active tissues, where they will be oxidized to give energy.

Front 28

Before the fatty acids produced from triglyceride hydrolysis can be used for energy what process must occur?

Back 28

Degradation and oxidation of fatty acids in the mitochondria.
- Degraded into acetyl-CoA by oxidation & H+ is released
- Acetyl-CoA enters Krebs cycle forms citric acid then breaks down to CO2 & H+ to for ATP (Lots-146)

Front 29

Whenever a greater quantity of carbs enters the body than can be used immediately is can be stored as __1__ , the excess is rapidly converted into __2__ and stored in this form in the adipose tissue.

Back 29

1. Glycogen

2. Triglycerides

Front 30

80% of cholesterol is used to form _______ in the liver.

Back 30

Cholic acid, which is used to make bile salts that promote digestion and absorption of fats.

Front 31

Whenever a greater quantity of carbs enters the body than can be used immediately is can be stored as __1__ , the excess is rapidly converted into __2__ and stored in this form in the adipose tissue.

Back 31

1. Glycogen

2. Triglycerides

Front 32

What is the most important function of cholesterol?

Back 32

It forms specialized structures in the cell and organelle membranes

Front 33

What is the most important function of all the phospholipids?

Back 33

participation in the formation of structural elements - mainly membranes - in cells throughout the body.

Front 34

What are the two forms of Cholesterol?

Back 34

Low density lipoproteins (LDLs) - "bad"
- responsible for atherosclerosis

High density lipoproteins (HDLs) - "good"

Front 35

How many different amino acids make up proteins in the body?

Back 35

20 - in large amounts in the body

10 - considered essential that the body cant synthesize and must be ingested

Front 36

Where are amino acids absorbed and how do they get into the cells?

Back 36

Absorbed in GI tract
Get into cell by either facilitated or active transport.

Front 37

Amino acids combine with one another when directed to by _______ to form proteins with cell.

Back 37

Messenger RNA