12

Question 1

Catabolism

Answer 1

breakdown

releases energy and CO2 (which must be removed)
produces nitrogen when breaking down proteins

Question 2

Anabolism

Answer 2

build up

ie. protein synthesis, proliferation of cells adnd tissues, cellular repair, synthesis of neurotransmitters and nucleic acids

take energy + building blocks –> larger molecules

Question 3

How are the tissues of metabolism specialized
What must it require

Answer 3

storage (adipose)
anabolism (liver)
waste removal (kidney)

nutrients and waste must circulate in the blood to reach these tissues (through concentration gradient) –> waste concentration in cells is high, nutrient concentration in blood is high

Question 4

Where do water-soluble molecules go after entering the blood

Answer 4

go to the liver directly via the portal vein bfore entering general circulation

Question 5

Where do fat-soluble molecules go after entering hte blood

Answer 5

go to the blood directly via the lymphatic system (cholymicrons)

Question 6

Where do unabsorbed molecuels go after entering the blood

Answer 6

excreted fro mthe GI tract

Question 8

What does the kidney do

Answer 8

water, minerals and metabolic wastes (urea) are ecreted through the bladder

controls excretion to maintain homeostasis (RAAS system)

maintenance of pH homeostasis (removes bicarb and hydrogen ions from the blood)

Question 9

How is the energy supply maintained

Answer 9

deitary intake (but not consuming food at all time, not steady)
- carbs, proteins, lipids –> CO2, heat

body storage

metabolism shifts depending on how long it has been since a meal and what fuel sources are available

Question 10

What happens if cells are not producing ATP

Answer 10

all pathways are affected
- DNA synthesis, glycolysis,

Question 11

What are the states of maintaining energy supply

Answer 11

fed state: using dietary fuel coming in
fasting state: using stores of food to maintain food supply

Question 12

Why is glucose the most critical fuel in the body

Answer 12

it is the primary energy source for the brain and RBC

energy for any type of cell in the body

Question 13

Does glucose levels change in fasting state

Answer 13

stay flat because all processes in the body reorient themselves to maintain glucose levels for as long as possible

Question 14

Why are RBC important

Answer 14

transport oxygen,
no RBC, no cells get oxygen

Question 15

What maintians blood glucose levels in the body

Answer 15

hormones
- insulin = lots of glucose
- glucagon = means blood glucose is low

Question 16

What happens in the fed state

Answer 16

glucose enters the blood from the GI tract – concentration of glucose in blood increases

glucose enters pancreas
- insulin released into the blood from beta cells
- glucagon production decreases in alpha cells

Question 17

How long does the fed state last

Answer 17

until absorption of food is complete
1-4 hours

Question 18

What cells can glucose NOT get into

Answer 18

muscle and adipose tissue

Question 19

What processes are turned on by liver after receiving glucose

Answer 19

immediate energy needs
replenishes glycogen stores
excess is converted to triglycerides

(acetyl Co-A, glucagon…)

Question 20

What is glycogen

Answer 20

stored from of glucose in animals
consists of chains of glucose molecules

Question 21

What do muscles do with glycogen

Answer 21

store glucsoe as glycogen for use as energy during activity and muscle contraction

Question 22

What doe sliver do with glycogen

Answer 22

stores glucose as glycogen to help regulate blood glucose levels

Question 23

What is glycogen synthesis

Answer 23

uses excess glucose-6-P to form glycogen chains

Question 24

What is glycogenolysis

Answer 24

glycogen degradation

breaks off glucose molecules, regenerating glucose 6-P
- re-enter glycolysis

Question 25

What is the glucose used for after being delivered by the blood

Answer 25

delivered to tissues - all cells can use it as fuel - adipose and muscle will only use glucose when insulin is present

Question 26

What do chylomicrons do

Answer 26

are the source of lipoproteins from diet --> formed in the intestines

Question 27

What is VLDL used for what produces it

Answer 27

liver triglycerides in VLDL are from excess carbohydrates and protein that has been converted for storage

Question 28

What are amino acids used for

Answer 28

used by liver to make blood and liver protein

Question 29

What happens to excess/free amino acids

Answer 29

enter the amino acid pool and can be used by all tissues to make protein or converted into other nitrogen-containing molecules (ex. neurotransmitters excess protein can be converted into fatty acids and stored as triglyceride

Question 30

When does the fasting state begin

Answer 30

1-4 hours after a meal

Question 31

What happens oin the fasted state

Answer 31

blood glucose levels have returned to fasting levels fasted state continues until food is consumed again and a new fed state begins the return of blood glucose to baseline signals the pancreas to decrease insulin secretion and glucagon secretion increases

Question 32

What does the fasted state signal

Answer 32

decrease insulin glucagon secretion increases the liver responds to these hormonal signals to control blood glucose levels - glucagon signals the need for glycogenolysis so blood levels do not fall too low

Question 33

What is the liver's role in maintaining blood glucose levels during fastor

Answer 33

fuel control centre can produce glucose from glycogenolysis or as glycogen stores are depleted, new glucose can be made from alternative sources (gluconeogensis)

Question 34

What is gluconeogensesis

Answer 34

reverse of glycolysis use of non-carb sources to produce glucose glycerol, lactate and amino acids can be used as precursors for glucose (ex. alanine) - provides a steady source of glucose to maintain blood glucose levels - aa breakdown will generate ammonia/urea

Question 35

What is the role of fatty acid in fasting state

Answer 35

major source of fuel adipose triglycerides are broken down (lipolysis) --> yields glycerol (for gluconeogensis) and free fatty acids - lypolysis is occuring at the sae time as glycogenolysis muscle and many other tissues can use FA or etone bodies for energy`

Question 36

What are ketone bodies (keto acids)

Answer 36

released from the liver from the brekadown of faty acids - can be used as alternative fuel for some tissues during fasting converted to acetyl-CoA and used in the TCA cycl

Question 37

What is the difference between FA and ketone bodies

Answer 37

FA = non polar ketone bodies = derived from FA but polar, soluble in blood

Question 38

What is the starved state

Answer 38

during continued fast, the body must change its ful metabolism - blood glucose is critical - taken from muscle --> muscle wasting

Question 39

What happens in starved state

Answer 39

muscle increases its use of FA as fuel decreases it use of ketone bodies (build up in blood) the brain = greater % of keton body for energy need --> decreases demand for glucose and gluconeogensis is slow