Nutrition Exam 3

Define anabolic pathways

use small compounds to build larger ones

Define catabolic pathways

breakdown large compounds into smaller ones

* results in the release of CO2, H2O and ATP

Which pathway uses energy

Anabolic

Which pathway produces energy

Catabolic

Energy currency of the cell

ATP

Anaerobic metabolism makes how many ATP

2

Aerobic metabolism makes how many ATP

30-32

In cellular respiration ETC what is the role of oxygen

it is the final electron acceptor

Where does glycolysis occur?

cytosol

Starting products for glycolysis

glucose

ending products of glycolysis

pyruvate

Does glycolysis require oxygen?

no

Is glycolysis reversible

yes

What are the two fates of pyruvate?

Lactate- anaerobic conditions

Acetyl CoA- **aerobic conditions**

is pyruvate to acetyl CoA reversible?

No

What happens to most citric acid cycle intermediates?

they get oxidized- lose electrons

What is the major role of the ETC

primary site of ATP production

Major metabolic products of the ETC

CO2

ATP

Water

When does anaerobic metabolism occur

* Oxygen isn’t present
* Cells do not have **mitochondria**

What does glycolysis convert glucose to anaerobically

pyruvate

Another name for fatty acid oxidation

Beta-oxidation

How is acetyl CoA created

fatty acids are cleaved 2 carbons at a time

Why is Acetyl CoA better than glucose?

It has more carbon-carbon bonds and allows more ATP to be produced

What do cells synthesize from pyruvate? What is it made from?

oxaloacetate

carbs or amino acids

What does a low carb consumption do?

decreases oxaloacetate production and slows TCA cycle

What created ketone bodies

Build-up of acetyl CoA

two types of protein metabolism and what they do

Glucogenic Amino acids- carbon skeleton used to form glucose

\
Ketogenic Amino Acids- carbon skeleton is used to for acetyl CoA (cannot be converted to glucose)

How are the deaminated amino groups excreted?

urea

Excess consumption beyond body’s kcal requirements from ANY energy-yielding nutrient will contribute to an increase in…

total body fat

During initial fasting, the body fuels itself with glucose from…

**glycogen** and fatty acids

If fasting for long term, the body adapts to use less… and use more…

glucose

ketone bodies

What water soluble vitamin can be stored for several months in the liver?

Cobalamin (B12)

What water-soluble vitamins can cause some toxicity?

Niacin (B3)

Pyridoxine (B6)

Vitamin C

What are all the water-soluble vitamins

Thiamin (B1)

Riboflavin (B2)

Niacin (B3)

Pantothenic acid (B5)

Pyridoxine (B6)

Cobalamin (B12)

Biotin (B7)

Folate (B9)

Vitamin C

What do coenzymes do?

activate enzymes

How are water-soluble vitamins excreted?

via the kidneys in urine

What water-soluble vitamins provide energy

Thiamin (B1)

Riboflavin (B2)

Niacin (B3)

What can destroy water-soluble vitamins

**cooking, heat, light**, air and alkaline substances

what techniques can preserve water-soluble vitamins?

**stir-fry**, steam, microwave, limit water and heat exposure

What vitamins are involved in neurotransmitter synthesis

**Niacin (B3), Pyridoxine (B6)**, folate, vitamin C

Coenzyme form of Thiamin (B1)

Thiamin pyrophosphate (TPP)

What is the function of Thiamin (B1)

decarboxylation

Good food source of Thiamin

Pork

What does TPP participate in?

glycolysis and the citric acid cycle

Thiamin deficiency that affects the peripheral nervous system and muscular systems

BeriBeri

Thiamin deficiency that affects the central nervous system

Wernicke-Korsakoff Syndrome

Two coenzyme forms of Riboflavin (B2)

Flavin mononucleotide (FMN)

**Flavin adenine dinucleotide (FAD)**

What B vitamin is light sensitive

Riboflavin (B2)

Good food source of Riboflavin

Milk

What is riboflavin’s role in TCA cycle

oxidation and reduction reactions

Riboflavin deficiency

Ariboflavinosis (cracked tissues around the mouth)

Two coenzyme forms of Niacin (B3)

Nicotinamide adenine dinucleotide (**NAD**)

Nicotinamide adenine dinucleotide phosphate (**NADP**)

Niacin deficiency

Pellagra

Niacin deficiency symptoms

Diarrhea

**Dermatitis**

Dementia

Death

Niacin toxicity side effects

**Tingling (painful)**

Flushing of skin

GI tract upset

Liver damage

What is a component of Coenzyme A that is needed to form Acetyl CoA

Pantothenic Acid

What Coenzyme participates in carboxylation?

Biotin

Good food sources of Pantothenic Acid

Widespread in foods

Good food sources of Biotin

Widespread in foods

Active coenzyme form of Pyridoxine (B6)

Pyridoxal phosphate (PLP)

Good food sources of B6

Meat, Poultry, Fish

B6 function in the body

transamination

Coenzyme form of Folate

Tetrahydrofolate (THFA)

Good Food Sources of Folate

Dark green leafy vegetables

What is THFA needed for

**1-carbon transfer** reactions that are needed for **DNA synthesis**

Deficiency of Folate

associated with elevated blood levels of homocystine

What type of problems can occur when a woman does not know she is pregnant and has a folate deficiency?

**Neural tube defects**, such as spina bifida and anencephaly

What foods are good sources of vitamin B12?

foods of **animal origin** only

functions of vitamin B12 coenzyme

**1-carbon transfer** reactions necessary for **DNA** **regulation**

parietal cells in the stomach release…

intrinsic factor which is used to absorb B12

What is removed by vitamin B12 and why

**the methyl group,** which donates it to homocysteine for it to become methionine

What population is at risk for vitamin B12 deficiencies

older adults

Deficiency of folate and/or vitamin B12

megaloblastic anemia

Functions of Vitamin C

Antioxidant and collagen synthesis

Good food sources of Vitamin C

citrus fruits and green/red peppers

Deficiency of Vitamin C

Scurvy

What does Scurvy disrupt?

the synthesis of collagen

Two types of vitamin A

provitamin A- carotenoids

preformed vitamin A- Retinal, Retinol, Retinoic acid

Good food sources for Vitamin A/Carotenoids

Sweet potatoes

Functions of Vitamin A

helps Vision

Immune function

Growth and development

How does vitamin A aid in immune function

growth, development, and maintenance of epithelial cells including the **mucus-secreting cells**

Functions of Carotenoids

Antioxidant properties

Vitamin A deficiency

progression to blindness

What is Vitamin D classified as

a vitamin and a **prohormone**

Active form of Vitamin D

calcitriol

Precursor to vitamin D

cholesterol

Good food sources for Vitamin D2

**fatty fish**- sardines and salmon

**fortified milk**

Where is Vitamin D metabolized? what is it metabolized to?

Kidneys to calcitriol

Functions of calcitriol

maintain blood levels of **calcium and phosphorus** to maintain bone health

increases **intestinal absorption** of calcium and phosphorus

vitamin D deficiency in children

Rickets

vitamin D deficiency in adults

Osteomalacia

What family is Vitamin E a part of

Tocopherols

Good food sources of vitamin E

Seed oils and almonds

Similar function between Vitamin C and Vitamin E

Antioxidant

What do antioxidants prevent

Free radicals

What does the accumulation of free radicals cause

oxidative stress

Function of vitamin E

stops lipid **peroxidation** damage to cell membranes

Function of vitamin K

activated **blood clotting** factors

Food sources of Vitamin K

Dark green leafy vegetables

also synthesized by bacteria in the colon

When choosing a dietary supplement, what should you look for

USP verified mark