2c Biological Molecules Flashcards Preview

IGCSE Biology > 2c Biological Molecules > Flashcards

Flashcards in 2c Biological Molecules Deck (21):
1

What elements are found in carbohydrates? (3)

- Carbon
- Hydrogen
- Oxygen

2

What elements are found in proteins? (5)

- Carbon
- Hydrogen
- Oxygen
- Nitrogen
- Sometimes Sulphur

3

What elements are found in lipids? (3)

- Carbon
- Hydrogen
- Oxygen

4

What is the structure of a lipid? (2)

- 3 fatty acids
- 1 glycerol molecule

5

What are oils? (2)

- Plant lipids
- Liquids at room temperature

6

What are proteins made of? (2)

- Long chains of amino acids.
- There are two different amino acids.

7

What are starch and glycogen made up of? (1)

- Simple sugars joined together

8

Give two examples of proteins found in the human body. (2)

- Collagen and keratin found in skin and nails.
- All enzymes
- Haemoglobin

9

What is the food test for starch? (2)

- Add iodine.
- If starch present, solution changes from brick orange to blue-black.

10

What is the test for glucose? (2)

- Heat with water and Benedict's solution.
- If glucose present, solution changes from blue to brick red.

11

What is the test for protein? (2)

- Add biuret reagent.
- If protein present, solution changes from blue to pink/purple.

12

What is the test for lipids/fat? (2)

- Add ethanol and boiling water.
- If fat present, milky white emulsion forms.

13

What is the function of genes? (2)

- Controls the activities of the cell.
- Determines which proteins are made.

14

What is an enzyme? (3)

- A biological catalyst
- which speeds up a reaction
- without being used up.

15

Define metabolism. (1)

- The rate at which chemical reactions take place in the body.

16

What is a substrate? (1)

- A molecule an enzyme acts upon.

17

What is the active site? (1)

- The area on an enzyme where a substrate attaches.

18

Describe and explain the affect of too high temperature on enzyme activity. (2)

- It decreases activity.
- Because the enzyme denatures and substrates can no longer fit the active site.

19

Describe and explain the effect decreasing the temperature on enzyme activity. (3)

- It decreases activity.
- Because there is lower kinetic energy.
- and fewer collisions between enzymes and substrates.

20

Why is it important we control our internal temperature? (2)

- Too high and the enzymes denature.
- Too low and the enzymes work too slowly.

21

Describe and explain the effect of too high or too low pH on enzyme activity. (2)

- Decreases activity.
- Enzyme denatures and substrates can no longer fit the active site.