Organism In The Environment

Question 1

What does mesophyll tissue do?

Answer 1

Where most of the photosynthesis in a plant occurs.

Question 2

What do xylem and phloem do?

Answer 2

Transport things like water, mineral ions and sucrose around the plant.

Question 3

What does the epidermal tissue do?

Answer 3

Covers the whole plant.

Question 4

What is the equation for photosynthesis?

Answer 4

Carbon dioxide + water -> glucose + oxygen

Question 5

What do chloroplast contain?

Answer 5

Chlorophyll.

Question 6

Where does photosynthesis occur?

Answer 6

In the chloroplast.

Question 7

What does the chlorophyll do?

Answer 7

Absorbs sunlight and uses its energy to convert CO2 and water into glucose.

Question 8

Where does photosynthesis occur?

Answer 8

In the leaves of all green plants.

Question 9

How are the leaves of a plant adapted?

Answer 9

Broad, giving them a large surface area for light to fall on. They contain chlorophyll in the chloroplast to absorb the light energy. They have air spaces that allow CO2 to get into the cells, and oxygen to leave by diffusion. They have veins which bring plenty of water to the cells of the leaf.

Question 10

How does algae absorb CO2?

Answer 10

They absorb CO2 dissolved in the water around them.

Question 11

What are the three limiting factors?

Answer 11

Light, CO2 and temperature.

Question 12

When is light a limiting factor?

Answer 12

At night.

Question 13

What happens if the temperature gets too high?

Answer 13

The enzymes in plant get destroyed and so therefore the rate of photosynthesis will fall.

Question 14

When else is temperature a limiting factor?

Answer 14

In the winter.

Question 15

Why would CO2 be a limiting factor?

Answer 15

The air is only made up of 0.04% CO2.

Question 16

Why at night is there more CO2?

Answer 16

Because plants don’t photosynthesise they only respire.

Question 17

How do greenhouses create the ideal temperatures?

Answer 17

They trap the sunlight, and so make sure temperature does become a limiting factor. In winter a heater is used. They uses shades and ventilation to cool things down. Light is always needed so artificial lights may be used at night.

Question 18

How do greenhouses stop CO2 becoming limiting?

Answer 18

The level of CO2 can be increased by the use of a paraffin heater. As it burns it releases CO2 as a by-product.

Question 19

How is glucose used for respiration?

Answer 19

They release energy which enables them to convert the rest of the glucose into various other useful substances, which they can use to build new cells and grow.

Question 20

How is glucose used for the cell wall?

Answer 20

Glucose is converted into cellulose for making strong cell walls.

Question 21

How is glucose used in making proteins?

Answer 21

It is combined with nitrate ions to make amino acids, which are then made into proteins.

Question 22

How is glucose stored in seeds?

Answer 22

Glucose is turned into lipids for storing in seeds.

Question 23

What is glucose turned into for storage?

Answer 23

Starch.

Question 24

Where is starch stored?

Answer 24

The roots, stems and leaves.

Question 25

Why is starch better for storing than glucose?

Answer 25

It is insoluble and cell of glucose would cause the plant to swell as it would draw in lots of water.

Question 26

Why is it important that starch is insoluble?

Answer 26

Doesn't affect the water balance of the plant.

Question 27

What factors affect the distribution of living organisms?

Answer 27

Temperature, nutrients, amount of light, availability of water, availability of oxygen and CO2.

Question 28

How does temperature effect the distribution of organisms?

Answer 28

It is a limiting factor therefore plants will be reduced in number, therefore the number of herbivores will be reduced.

Question 29

How does the level of nutrients effect the distribution of organisms?

Answer 29

It has a big impact as carnivorous plants thrive where nitrate levels are low because the can trap and digest animal prey. The nitrates they need are provided when they break down the animal protein.

Question 30

How does light effect the distribution of organisms?

Answer 30

It is a limiting factor. Some plants may survive as they have more chlorophyll and bigger leaves. Moreover the breeding cycles of many animal and plant species are linked to the day length. They can only breed in regions where day length and light intensity are right for them.

Question 31

How does water effect the distribution of organisms?

Answer 31

Distribution changes after it rains. A large number of plants grow, flower and set seeds very quickly where water is available. They are then eaten by animals that move into the area to take advantage of them.

Question 32

How does CO2 and O2 levels effect the distribution of organisms?

Answer 32

Some invertebrates can survive in areas of low oxygen however some fish need high levels of O2. This factor more affects water not the land as there is plenty CO2 and O2 in the air.

Question 33

What are quadrats used to measure?

Answer 33

The size of population of plants.

Question 34

What is the first thing to do when taking a quadrat?

Answer 34

Place it on the ground at a random point in the first sample area. E.g. divide the area into a grid and use a random number generator to pick coordinates.

Question 35

What is the second step of taking a quadrat?

Answer 35

Count all the organisms within the quadrat, then repeat the first step and work out the mean number of organisms in the first area.

Question 36

What is the last step when taking a quadrat?

Answer 36

Repeat the first steps but take the readings in the second area. Then compare the to means of the areas.

Question 37

What must you ensure you do when taking a quadrat?

Answer 37

Use the same sample size, makes your results valid.

Question 38

What does a transect show?

Answer 38

How the distribution of organisms changes along a line.

Question 39

What are the steps for finding the transect result?

Answer 39

Mark out a line in the area you want to study using a tape measure, then collect data along the line, you can do this by counting the organisms, or you can use quadrats placed at intervals.

Question 40

How can you increase the reliability of the quadrat and transect results?

Answer 40

Use a larger sample size as it is more representative of the whole population.

Question 41

What else could you use a transect to measure?

Answer 41

Physical factors such as light levels and soil pH.