Topic 3.8: Photosynthesis

Question 1

What does all life need?

Answer 1

energy

Question 2

How do heterotrophs get and use their energy?

Answer 2

get their energy from “eating others”; consumers or other organisms; consume organic molecules; making energy & organic molecules from ingesting organic molecules; glucose+oxygen yields carbon dioxide+water+energy; C₆H₁₂O₆+6O₂ yields 6CO₂+6H₂O+ATP

Question 3

How do autotrops get and use their energy?(6)

Answer 3

get their energy from “self”; get their energy form sunlight or chemicals; use light energy to synthesize organic molecules; making energy & organic molecules from light energy; carbon dioxide+water+energy yields glucose+oxygen; 6CO₂+6H₂O+light energy yields C₆H₁₂O₆ + 6O₂

Question 4

What is the purpose of the leaves?

Answer 4

to collect sunlight

Question 5

What is the purpose of the stomates?

Answer 5

to collect carbon dioxide for gas exchange

Question 6

What is the purpose of the roots?(2)

Answer 6

uptake of water; uptake of nutrients

Question 7

What are the parts of the chloroplast?(4)

Answer 7

double membrane; stroma; thylakoid sacs; grana stacks

Question 8

What is the importance of chlorophyll and the electron transport chain in the thylakoid membrane?

Answer 8

There is a build up of H_⁺ (proton) gradient within the thylakoid sac

Question 9

What are th best and worst wavelengths for chlorophyll a?(2)

Answer 9

absorbs red and blue light the best; reflects green so it is least absorbant

Question 10

What do galvometers measure?

Answer 10

galvometers measure light transmittance

Question 11

What does the light reactions do?

Answer 11

convert solar energy to chemical energy(ATP)

Question 12

What does the calvin cycle/light independent reaction do?

Answer 12

uses chemical energy (NADPH & ATP) to reduce CO₂ to build C₆H₁₂O₆ (sugars)

Question 13

What is light intensity?

Answer 13

varies inversely with the square of the distance (farther away, less intense)