Biochem Exam 1: Set 1 (Eating/Fasting, Collagen, Amino Acids)

Question 1

normal blood glucose levels

Answer 1

80-100 mg/dL (4.4-5.6mM)

Question 2

This tissue can ONLY use glucose for energy

Answer 2

red blood cells

Question 3

Amount of energy provided by carbohydrates

Answer 3

4kcal/gm

Question 4

Amount of energy provided by lipids

Answer 4

9kcal/gm

Question 5

Amount of energy provided by protein

Answer 5

4kcal/gm

Question 6

Amount of energy provided by ethanol

Answer 6

7kcal/gm

Question 7

Most ethanol is metabolized here

Answer 7

liver

Question 8

Most energy is stored in the form of ___

Answer 8

adipose tissue

Question 9

Name the essential carbohydrates

Answer 9

There are no essential carbohydrates

Question 10

Carbohydrates are stored in the form of ____ which is found where in the body?

Answer 10

Glycogen

Found in: muscle tissue, liver, kidney

Question 11

Body glycogen stores can provide energy for how long?

Answer 11

~24 hours

Question 12

White and brown adipose tissues differ in their…

Answer 12

organization, location, # of mitochondria, vascularity, and function

Question 13

Adipose tissue stores fat in the form of…

Answer 13

an intracellular droplet of insoluable triacylglycerols

Question 14

_____ frees fatty acids by hydrolyzing triglyceride

Answer 14

hormone-sensitive lipase

Question 15

What is the structure of linolenic acid?

Answer 15

18:3D9,12,15

Question 16

What is the structure of linoleic acid?

Answer 16

18:2D9,12

Question 17

What is the structure of stearic acid?

Answer 17

18:0

Question 18

What is the structure of palmitic acid?

Answer 18

16:0

Question 19

Protein is stored in the form of…

Answer 19

No storage form of protein

Question 20

A negative nitrogen balance is indicative of…

Answer 20

a serious infection or starvation

Question 21

What are the essential amino acids?

Answer 21

His, Ile, Leu, Lys, Met, Phe, Thr, Trp, Val

Question 22

An individual’s energy requirement is calculated by:

Answer 22

Energy Requirement= BMR x activity level x stress factor

Question 23

Respiratory Quotient=

Answer 23

RQ= (CO2 produced)/(O2 consumed)

Question 24

Folate deficiency impairs what?

Answer 24

required for purine synthesis, deficiency impairs cell division/growth, presents as neural tube defects

Question 25

What is scurvy?

Answer 25

vitamin C deficiency- connective tissue weakness

Question 26

What is the medical term for starvation and how is it treated?

Answer 26

Marasmus, initially treat with a diet of skim milk and vegetable oil

Question 27

What is Kwashiorkor syndrome?

Answer 27

protein deficiency but total calories are ok

Question 28

BMI has units of ___

Answer 28

kg/m^2

Question 29

An overweight patient has a BMI of ____, and an obese patient has a BMI of ____

Answer 29

overweight: 25-29 obese: 30

Question 30

What organ will break down glycogen and release glucose into the blood during initial fasting?

Answer 30

liver

Question 31

Insulin is released by the...

Answer 31

pancreas

Question 32

What determines a protein's structure?

Answer 32

amino acid sequence

Question 33

Explain marginal stability of proteins

Answer 33

easily denatured by changes in temperature, pH, and ionic strength

Question 34

Phosphorylation typically targets which amino acids?

Answer 34

Ser, Thr, Tyr

Question 35

Acetylation typically targets which amino acids?

Answer 35

Lys

Question 36

How does HbA1c differ from other forms of hemoglobin?

Answer 36

HbA1c is glycosylated on the N-terminus of the beta chain

Question 37

Where does glycosylation of secreted proteins occur?

Answer 37

golgi apparatus

Question 38

What is the average life time of a red blood cell?

Answer 38

~120 days

Question 39

Heme iron in hemoglobin is in what state when it is bound by oxygen?

Answer 39

Fe2+

Question 40

A sigmoidal curve on a plot of substrate saturation vs. substrate concentration is indicative of what?

Answer 40

cooperative binding (ex. hemoglobin)

Question 41

Oxygenated hemoglobin is in what state?

Answer 41

R state (relaxed)

Question 42

What is the basic structural unit of collagen

Answer 42

tropocollagen

Question 43

Which two amino acids are necessary for the left hand triple helix of collagen?

Answer 43

proline- structurally rigid | glycine- every 3rd residue, amide of hydrogen H bonds to carbonyl oxygen of different side chains

Question 44

Vitamin C is required for what stabilizing reaction in collagen?

Answer 44

conversion of proline to 4-hydroxyproline

Question 45

How does copper deficiency weaken collagen?

Answer 45

Lysyl oxidase (copper dependent enzyme) converts Lys to allysine, which spontaneously forms aldol cross links

Question 46

Where does lysyl oxidase form crosslinks in collagen?

Answer 46

Extracellularly

Question 47

Osteogenesis Imperfecta and Ehlers-Danlos syndrome are both genetic disorders that effect...

Answer 47

collagen

Question 48

How can low exposure to sunlight cause weak bones?

Answer 48

UV light synthesizes conversion from cholesterol into Vitamin D. Calcium can also increase vitamin D synthesis. Without sunlight Ca resorption from bones to increase vitamin D.