Anatomy And Physiology Ii Metabolism

Front 1

define nutrients

Back 1

substance in food used by body to promote normal growth, maintenance and repair: essential nutrients can't be made by the body and must be supplied in the diet

Front 2

what are the three major nutrients?

Back 2

carbohydrates, lipids and proteins

Front 3

is anabolism synthetic or degradative?

Back 3

synthetic: synthesizing to make something we can store away

Front 4

is catabolism synthetic or degradative?

Back 4

degradative: break down of things to create the potential for energy

Front 5

describe the three stages of metabolism of energy containing nutrients

Back 5

1: digestion in GI tract lumen
2: anabolism and formation of catabolic intermediates within tissue cells
3: oxidative breakdown in mitochondria of tissue cells

Front 6

what is the equation for oxidation reduction reactions?

Back 6

C6H12O6 + 6O2 yeilds 6CO2 + 6H2O + ATP

Front 7

oxidation occurs...

Back 7

via the gain of oxygen or loss of hydrogen: oxidized substance looses electrons (because H is positive, it has an electron attached to it which it takes with it when it is forced out

Front 8

whenever one substance loses electrons (is oxidized), another substance gains them: known as...

Back 8

reduced

Front 9

oxidation and reduction are said to be what?

Back 9

"coupled": you can't separate them

Front 10

what are dehydrogenases?

Back 10

enzymes catalyzing oxidation-reduction reactions by removing hydrogen

Front 11

what are oxidases?

Back 11

enzymes catalyzing transfer of oxygen

Front 12

what are NAD and FAD?

Back 12

vitamin B's
NAD derived from niacin; FAD derived from ribolfavin

Front 13

what is substrate-level phosphorylation?

Back 13

high-energy phosphate group transferred directly from phosphorylated substrate to ADP

Front 14

what is oxidative phosphorylation?

Back 14

-most energy that goes into ATP captured this way
-energy gained by oxidizing food products is used to pump hydrogen across the membrane: creates gradient, hydrogen moves back across membrane down gradient a phosphate group is added to ADP
-occurs in mitochondria

Front 15

know figure on slide 9

Back 15

KNOW IT

Front 16

what is the process for the oxidation of glucose?

Back 16

1 molecule glucose + 6 molecules oxygen yeilds 6 molecules water + 6 molecules carbon dioxide + 36 molecules ATP + heat
-involves three pathways

Front 17

what is produced by the oxidation of glucose?

Back 17

6 water molecules, 6 carbon dioxide molecules and 36 ATPs produced in total

Front 18

figure on slide 16 is a good summary

Back 18

know it

Front 19

what is glycogenesis?

Back 19

synthesis of glycogen
-glycogen is storage form of glucose
-glycogen synthase attaches glucose molecules to create chain
-most active in liver and skeletal muscle cells
-occurs under high ATP conditions

Front 20

what is glycogenolysis?

Back 20

glycogen lysis (splitting)
-glycogen phosphorylase
-occurs primarily in liver
-occurs during low blood glucose states

Front 21

what is gluconegenesis?

Back 21

formation of new sugar from noncarbohydrate molecules (glycerol and amino acids)
-occurs in liver

Front 22

how are lipids metabolised?

Back 22

by the oxidation of glycerol and fatty acids (the two components of neutral lipids)
-glycerol yields 18 ATP

Front 23

what are the main phases to glycolysis?

Back 23

-activate
-split the glucose in to 2 glyceraldehyde phosphate
-oxidize

Front 24

where are excess fatty acids and glycerol stored?

Back 24

subcutaneous tissue and fat depots

Front 25

describe triglyceride synthesis or lipogenesis

Back 25

-occurs when ATP/glucose high
-acetyl CoA and glyceraldehyde phosphate accumulate
-Acetyl CoA condensed to make fatty acids; consequently glucose easily converted to fatty acids
-glyceraldehyde phosphate converted to glycerol and on to fat

Front 26

describe lipolysis

Back 26

breakdown of stored fats
-liver, cardiac muscle, and resting skeletal muscle prefer fats

Front 27

what happens if you dont eat carbohydrates and drive acetyl CoA in to ketone bodies?

Back 27

the body will go into acidosis: you can smell this on people's breath, it will smell fruity, this is the acid the body is trying to get rid of

Front 28

which does the body use in the absorptive, or fed, state? anabolism or catabolism?

Back 28

anabolism

Front 29

figures on slides 23 and 24

Back 29

know them

Front 30

what is released in response to the sympathetic nervous system to act on liver, skeletal muscle and adipose promote same effects and glucagon?

Back 30

epinephrine: released from the adrenal medulla

Front 31

what 4 random things influence metabolism and nutrient flow?

Back 31

-growth hormone (anti-insulin effects)
-thyroxine
-sex hormones
-corticosteroids

Front 32

what is the liver's role in the metabolism?

Back 32

500 or more metabolic functions
-packages fatty acids for storage/transportation
-synthesizes plasma proteins
-forms nonessential amino acids, converts ammonia resulting from their deamination to urea
-stores glucose as glycogen and regulates blood sugar levels
-stores certain vitamins (A, D, and B12)
-conserves iron from worn-out rbc's
-degrades hormones
-detoxifies substances like alcohol and drugs

Front 33

triglycerides and cholesterol transported to and from tissue cells in body fluids bound to what?

Back 33

lipoproteins

Front 34

risk of atherosclerosis is increased with plasma cholesterol levels greater than what?

Back 34

200 mg/dl blood

Front 35

what is the body energy balance?

Back 35

-from 1st law of thermodynamics: energy neither created nor destroyed, only converted from one form to another
-a dynamic balance exists between the body's energy intake and its energy output
-energy intake = total energy output (heat + work + energy storage)

Front 36

what are the neural signals of food intake?

Back 36

-from digestive tract vagus nerve afferents transmit different patterns of impulses to brain in response to protein versus carboydrate

Front 37

what are the nutrient signals for food intake?

Back 37

-glucose receptors in brain depress eating
-elevated amino acid levels depress eating: mechanism not known
-greater fat reserves, larger amount of fatty acids and leptin (peptide released by adipose cells) released to blood, inhibit eating

Front 38

what are the hormones associated with the regulation of food intake?

Back 38

-insulin and CCK depress hunger
-glucagon and epinephrine stimulate hunger

Front 39

what is the body temperature associated with the regulation of food intake?

Back 39

if increased, eating behavior inhibited

Front 40

what is leptin associated with the regulation of food intake?

Back 40

overall satiety signal
-released by adipose tissue in reponse to increase in fat mass
-leptin binds to receptors of the choroid plexus
-leptin suppresses secretion of NPY (appetite stimulant)

Front 41

define metabolic rate

Back 41

body's rate of energy output (total heat produced by chemical and mechanical means/hour)
-direct measurement by calorimeter
-indirect measurement by respirometer

Front 42

define basal metabolic rate (BMR)

Back 42

energy body needs to perform only the most essential activities
-reported in kcal/m2/hour
-standard conditions are posabsorptive state (no eating for past 12 hours), reclining, relaxed 20-25 degrees C
-factors increasing = surface area, younger age, male, body temperature, stress, thyroxine (most important hormonal factor)

Front 43

define total metabolic rate (TMR)

Back 43

total rate of kilocalorie consumption to fuel all activities (involuntary and voluntary)
-BMR accounts for large part of TMR