B2.2 Organisms In The Environment

Question 1

What four things do plants need to grow?

Answer 1

Carbon dioxide
Water
Nutrients
Light

Question 2

What’s the equation for photosynthesis?

Answer 2

Carbon dioxide + water -(light energy)-> oxygen + glucose

Question 3

In words what actually happens during photosynthesis?

Answer 3

Light enemy is absorbed by the chlorophyll, a substance found in the chloroplasts. This energy is then used to convert carbon dioxide from the air and water from the soil into a simple sugar called glucose. Oxygen is also produced and released as a gas.

Question 4

How do you test a leaf for starch?

Answer 4

Put a leaf in boiling water for a minute to soften it
Place a leaf into a test tube half full of ethanol
Place the test tube in hot water for 10 mins
Return the leaf to the hot water for a min
Spread the leaf out on a tile and cover it in iodine solution.
The iodine turns black in the presence of starch

Question 5

What happens to photosynthesis as you increase the concentration of carbon dioxide?

Answer 5

The rate of photosynthesis increases until it levels off when co2 is no longer a limiting factor.

Question 6

What happens to photosynthesis as you increase the temperature?

Answer 6

The higher the temperature, the quicker the rate of photosynthesis until the enzymes start to denature and the rate of photosynthesis decreases

Question 7

What happens to photosynthesis as light intensity increases?

Answer 7

The more light intensity the quicker the rate of photosynthesis until there is no more light to be emitted.

Question 8

What would you measure to determine how much photosynthesis is happening when light intensity is increased?

Answer 8

Amount of bubbles

More bubble more light intensity

Question 9

What do plants do with the glucose they produce?

Answer 9

Used to provide energy for chemical processes in the cell (by respiration)
Turned into sucrose and transported to other parts of the plant
Turned into starch and stored in the cell as starch grains
In darkness the starch is changed back into glucose and transported out of the cell

Question 10

What is glucose?

Answer 10

Small soluble molecule

Question 11

What is starch?

Answer 11

Long chain of glucose, insoluble (doesn’t dissolve in water)

Ideal for storage

Question 12

How do plants store food?

Answer 12

They turn the glucose into an insoluble starch which makes it ideal and easy to store

Question 13

What other materials do plants and algae need to make protein?

Answer 13

Nitrates
Phosphates
Potassium (helps the enzymes)

Question 14

What happens to a monomer when polymerisation happens? Give an example.

Answer 14

Turns to a polymer

Glucose is a monomer and then it turns to starch which is a polymer

Question 15

Where’s cellulose found?

Answer 15

Plant cell walls

Question 16

What physical factors affect organisms?

Answer 16

Temperature
Light intensity
Amount of CO2 and O2
Water
Nutrients

Question 17

Give one way leaves are adapted for photosynthesis?

Answer 17

Leaves are thin for diffusion

Question 18

What are transects?

Answer 18

They’re tape measures put across a habitat. You then use quadrants at different points on the transects. It allows you to measure how the the habitat is changing along a period

Question 19

Where would you throw a quadrat?

Answer 19

Have an area of land behind you and randomly throw it behind you so you don’t get bias results ( you might biasedly pick an area with lots of flowers)