The Basics: Fuel Metabolism and Nutrition

Question 1

Conversion for kilograms to pounds

Answer 1

one kilogram is 2.2 pounds

Question 2

How many calories per gram does alcohol produce?

Answer 2

Seven kcal/g

Question 3

What is the percentage of water stored in adipose tissue?

Answer 3

fifteen percent

Question 4

What is the percentage of water store in muscle tissue?

Answer 4

eighty percent

Question 5

What is the calculation for Basal Metabolic rate?

Answer 5

It is 24 kcal/kg body weight/day

Question 6

What are the essential fatty acids? Why are they important?

Answer 6

Linoleic and alpha-linoleic acids

They are the precursors of the polyunsaturated fatty acids required for the synthesis of prostaglandins and other eicosanoids: arachidonic acid and eicosapentaenoic acid. Found in high levels in the fish oils.

Question 7

What are the essential amino acids?

Answer 7

They are the amino acids (nine of them) that cannoit by synthesized in the body, and need to be obtained from the body:

• histidine -isoleucine -leucine
• lysine -methionine -phenylalanine
• threonine -tryptophan -valine

***Arginine can only be synthesized in limited amounts and must be present in the diet for growth needs

Question 8

Nitrogenous waste that is excreted in the urine:

Answer 8

urea, uric acid, creatinine, and ammonia

Question 9

role of amylase in digestion of starch:

Answer 9

cleave starch to disaccharides and oligosaccharides, further cleavage to glucose requires maltase and isomaltase enzymes, found on brush border of intestinal epithelial cells

Question 10

What are the enzymes that help cleave sucrose and lactose?

Answer 10

Sucrase and lactase

Question 11

Where are sucrase and lactase found?

Answer 11

Part of the complexes on the surface of intestinal epithelial cells

Question 12

Sucrase converts sucrose to

Answer 12

fructose and glucose

Question 13

lactase converts lactose to

Answer 13

glucose and galactose

Question 14

Digestion of fats:

Answer 14

Triacylglycerols are emulsified in intestine by bile salts, digested by pancreatic lipse to 2-monoacylglycerols and fatty acids.

These are packaged into micelles by bile salts and absorbed into intestinal epithelial cells, and reconverted to triacylglycerols.

Triacylglycerols are packaged into chylomicrons which enter the lymph and then into the blood.

Question 15

Digestion of protein:

Answer 15

Digested first by pepsin in the stomach.

Pancrease produces trypsin, chymotrypsin, elastase, carboxypeptidases.

Aminopeptidases, dipeptidases and tripeptidases are associated with intestinal epithelial cells.

Proteins are degraded into mixture of amino acids, absorbed by epithelial cells and then passed into blood.

Question 16

Excess glucose in the liver is converted into:

Answer 16

glycogen and fatty acids/glycerol moiety that then form triacylglycerols and packaged into VLDL

Question 17

Amino acids in the fed-state are used to produce nitrogenous compounds such as:

Answer 17

heme, creatine phosphate, epinephrine, and DNA/RNA bases

Question 18

Normal Triglyceride level

Answer 18

less than/equal to 150

Question 19

When does Glycogenolysis begin?

Answer 19

about 2 to 3 hours after a meal

Question 20

How long do glycogen stores last?

Answer 20

about 30 hours

Question 21

When does the liver begin gluconeogenesis?

Answer 21

about 4 to 6 hours after a meal

Question 22

What are the Ketone Bodies?

Answer 22

Acetoacetate and beta-hydroxybutyrate

Question 23

During Fasting, muscle protein is degraded and released into the blood, mainly as:

Answer 23

Alanine and Glutamine

They travel to liver and are converted to glucose or ketone bodies, nitrogen is converted into urea

Question 24

When does body enter the starved state?

Answer 24

after three to five days of fasting

Question 25

In the starved state, what is the brain’s new source of fuel?

Answer 25

Ketone bodies, thus decreasing its use of glucose

Question 26

In the starved state, what becomes the body’s primary source of energy?

Answer 26

Fat stores: the length of time that a person can survive without food depends mainly on the amount of fat stored in the adipose tissue

Question 27

What is Kwashiorkor?

Answer 27

Diet is adequate in calories, but low in protein. This deficiency causes decreases in protein synthesis (albumin) eventually affecting regeneration of intestinal epithelium, thus leading to malabsorption.

Characterized by hepatomegaly and distended abdomen. Commonly occurs in children in third world countries.

Question 28

What is Marasmus?

Answer 28

The diet is deficient in both protein and calories.

Question 29

What is the largest amount of stored energy in the body?

Answer 29

Triacylglycerol (fat stores)

Question 30

The energy source reserved for strenuous muscular activity is….

Answer 30

Muscle glycogen

Question 31

The primary source of carbon for maintaining blood glucose levels during an overnight fast…..

Answer 31

Liver Glycogen

Question 32

The major precursor of urea in the urine….

Answer 32

protein (esp. alanine and glutamine)

Question 33

After a fast of a few days, KBs become an important fuel for this organ….

Answer 33

The brain

Question 34

Fatty acids are not a significant fuel source at any time for these cells…..

Answer 34

RBCs

Question 35

This tissue converts lactate from muscle to a fuel for other tissues….

Answer 35

The liver