Biology - Review Qns - 5 Flashcards Preview

LPC 2018 Biology > Biology - Review Qns - 5 > Flashcards

Flashcards in Biology - Review Qns - 5 Deck (26):
1

What are the 2 stages of Photosynthesis?

1) light-dependent reactions
2) light-independent reactions.

2

What do Chloroplasts contain?

4 Items

Thylakoid membranes
Grana
Stroma (fluid)
Their own DNA and ribosomes

3

Where do the light dependent reactions occur?

On the grana

4

What are the light dependent reactions?

3 steps

Light energy is trapped by chlorophyll
Water is split
Oxygen is released as a product.

5

Where do the light independent reactions occur?

In the stroma

6

What are the light indepent reactions?

Carbon dioxide is reduced to form glucose

7

Write the balanced chemical equation for photosynthesis.

6 CO₂ + 6 H₂O →  C₆H₁₂O₆ + 6 O₂

8

Key Factors afecting rate of photosynthesis?

3 Key Factors

• An increase in carbon dioxide levels can increase the rate of photosynthesis.
• An increase in light intensity can increase the rate of photosynthesis.
• The availability of chloroplasts to carry out photosynthesis can

9

What happens outside optimum temperature range for phtosynthesis?

Too cold → rate of reaction will be too slow.
Too hot →  enzymes in chloroplasts can denature
 
 

10

What happens when stomata close?

Plant can no longer exchange oxygen and carbon dioxide,
→  the rate of photosynthesis decreases.

11

What is the benefit of closing its stomata?

Minimizes water loss

12

Which organic molecule is used as the primary source of energy for most cells?

Glucose

13

What does ATP do?

The energy released in the breakdown of glucose is carried by ATP.

14

What is Glycosis?

The first stage of cellular respiration.

15

How many ATP molecules can be created from one glucose molecule during glycolysis?

Two ATP (per glucose molecule) are created during glycolysis

16

What are the stages of aerobic cellular respiration?

3 stages

Glycolysis
The Krebs cycle
The electron transport chain.

17

What are the contents of Mitochondria?

3 components

Cristae (folded membranes)
Matrix (fluid)
Their own circular DNA (mtDNA) and ribosomes.

18

Details on Glycosis

Location
Product
Reaction

Glycolysis occurs in the cytosol
Glycolysis yields 2 ATP.
Glucose is converted into two pyruvate molecules.

19

Details on Krebs cycle

Location
Product
Reaction

Occurs in the matrix of the mitochondria
Yields 2 ATP.
Pyruvate is broken down into carbon dioxide.

20

Details on electron transport chain

Location
Product
Reaction

Occurs in the cristae of the mitochondria
Yields 26–28 ATP.
Oxygen accepts the hydrogen ions that are used to generate a large amount of energy

21

Product of anaerobic respiration in animals?

Lactic Acid

22

Product of anaerobic respiration in yeast?

Ethanol and Carbon Dioxide

23

Eficiency of Aerobic vs Anaerobic respiration?

ATP of Aerobic vs Anaerobic

Aerobic respiration yields 30–32 ATP per glucose molecule
Anaerobic respiration yields 2 ATP per glucose molecule

24

What is the effect of temperature on cellular respiration?

When the temperature is above or below the optimum range, the rate of cellular respiration is slower.
Below optimum: insufficient energy to activate
Above optimum: protiens start to denature

25

What is the effect of glucose concentration on cellular respiration?

Glucose is a substrate of glycolysis, therefore an increase in glucose availability will increase the rate of cellular respiration.

26

What is the effect of oxygen concentration on cellular respiration?

Oxygen is a substrate of the electron transport chain, therefore an increase in oxygen concentration will increase the rate of aerobic cellular respiration.