L. 13 Metabolism

Question 1

LO

Answer 1

• Distinguish between macronutrients and micronutrients
• Characterise the terms anobolism and catabolism
• Describe the composition of fats, carbohydrates and proteins
• Explain how ATP can power cellular processes
• Compare and contrast different nutritional sources of protein
• Understand the basics of how fats, carbohydrates and proteins can be interconverted via metabolism

Question 2

Metabolism

Answer 2

• All of the chemical reactions that take place in the body
• Can be anabolic or catabolic

Question 3

Anabolic Vs Catabolic reactions

Answer 3

Anabolic:
- Building, smaller into larger

Catabolic:
- Destroying, larger broken into smaller molecules

Question 4

Macronutrients Vs Micronutrients

Answer 4

Macronutrients:
- Larger
- Serving as fuel and construction elements

Micronutrients:
- Usually cofactors to help enzymes (coenzymes)

Question 5

Carbohydrates

Answer 5

• long strings of sugars (6C molecules bind at 1-4 & 1-6 bonds)
• Common eg. Glycogen

Hexagon ‘train’

Question 6

Glycocidic bond formation

Answer 6

Chains of 6C sugars (glucose)

• Forms H2O with anabolism via condensation reactions
• Hydrolysis of Glycogen = catabolism (uses H2O)

Question 7

Glycogen storage

Answer 7

Stored in many cells, especially liver & skeletal muscle
- Liver is very altruistic, releases sugar into the blood stream
- Muscles prefer to hold onto it

Question 8

Amino Acids

Answer 8

• Absorbed by the small intestine into the blood stream before being anabolised into proteins
• 11 non-essential
• 9 essential

All essential amino acids are made by plants, can be consumed from the plant, or from an animal that ate the plant

Question 9

Drawing amino acid

Answer 9

[heft]

Top = H
LHS = NH2 amino group
RHS = COOH carboxyl group
Mid = C
Bottom = R group

HONC rule
H = 1 bond
O = 2 bond
N = 3 bond
C = 4 bond

Question 10

Fats

Answer 10

• Stored in adipose tissue
• Travel around body in lipoproteins (vesicles)
• Lipoproteins are coated by phospholipids (hydrophilic)
• High density lipoproteins = good, go to liver to be catabolized
• Low density lipoproteins (LDL) = bad, go into cell and supply with fat
• Saturated fat = bad
• Unsaturated = good (kink double bond)

Question 11

Triglyceride

Answer 11

3x Fatty acid chains on carbons

[heft]

Fatty acid chain:
C/\/\/\/

Question 12

Phosphate

Answer 12

• Hydrophilic due to charges

[heft]

Question 13

ATP (Adenosine Triphosphate)

Answer 13

• Supplies energy for metabolic processes

Pi is donated to a protein and causes 2 negative ends to repel, physically changing the shape of the protein, until an enzyme removes the Pi, allowing the protein to return to original shape.

[heft]

Question 14

Fats, Proteins & Carbohydrates

Answer 14

• Interconvertable and do not stay as is once eaten.
• Get broken down and rearranged, then rebuilt

[heft]