Respiration & Movement of Water through the plant

Question 1

Describe cellular respiration?

Answer 1

Respiration is the process by which living things release energy from stored sugars.
In the presence of oxygen respiration is aerobic.
In the absence of oxygen respiration is anaerobic.
Anaerobic respiration allows a plant to survive low oxygen situations such as waterlogged.
Respiration takes place in all living cells. Whereas photosynthesis only takes place in certain tissues.
The equation for respiration is the opposite of photosynthesis.
During photosynthesis plants make their own food using energy from the sun.
During respiration they break down this food to release energy to enable growth and other chemical processes.

Question 2

Definition of aerobic respiration?

Answer 2

The process by which sugars are broken down in the presence of oxygen to release chemical energy for biological processes. Water & Co2 are bi-products.

Question 3

What is the main type of respiration?

Answer 3

Aerobic respiration.

Question 4

What type of respiration occurs when there is no oxygen to the cell?

Answer 4

Anaerobic respiration.

Question 5

Equation for aerobic respiration.

Answer 5

Glucose + Oxygen = Carbon Dioxide + Water + Energy (high yield)

Question 6

Equation for anaerobic respiration.

Answer 6

Glucose = Ethanol + Carbon Dioxide + Energy (low yield)

Question 7

Which type of respiration produces the most energy?

Answer 7

Aerobic respiration

Question 8

Where does respiration happen?

Answer 8

In all cells. All of the time.

Question 9

Where does aerobic respiration occur?

Answer 9

In the mitochondria

Question 10

Where does anaerobic respiration occur?

Answer 10

in the cytoplasm of the cell.

Question 11

What are the 5 differences between respiration and photosynthesis processes?

Answer 11

Photosynthesis
Happens in the chloroplasts
Only happens in cells containing chloroplasts - mainly in the mesophyll cells..
Happens in the day when light is available.
Uses light energy to create sugars.
Co2 and Water are used in the process
O2 and sugars are products of the process

Respiration
Happens in the mitochondria
Happens in all cells all the time.
Breaks downs sugars to create energy.
O2 and sugars are used in the process
Co2 and energy are products of the process

Question 12

How does oxygen reach the plant cells? 4 ways!

Answer 12

1. Across the surface of all plant parts by diffusion
2. Via stomata in the leaves via diffusion
3. Via lenticels in the stem via diffusion.
4. Produced within the plant as a product of photosynthesis. So plant will use some of it’s own homemade oxygen!

Question 13

Where might rapid aerobic respiration occur?

Answer 13

Companion cells of phloem
Meristematic tissue
Growth of seedling
Young tissue

Question 14

Where might anaerobic respiration occur?

Answer 14

Waterlogged soil
Compacted soil
Early stages of seed germination before the seed coat has split and the seed is swollen with water.
The centre of a large fruit in storage.

Question 15

What factors can affect respiration?

Answer 15

Temperature
Water
Oxygen availability
Carbon dioxide levels.

Question 16

How does temperature affect respiration?

Answer 16

Affects enzymes. Rate of respiration generally increases with temperature up to about 25 degrees and decreases as temperature drops.
Temperature can be increased or decreased in greenhouse to help control rate of respiration. (heater/damping down/shade/open vents)

Question 17

How does Oxygen affect respiration?

Answer 17

It is an oxidising agent. As oxygen rate increases the rate of respiration increased up to a certain point.
Insufficient oxygen and anaerobic respiration takes over. Ethanol can build up.
Ventilation & good soil structure, drainage and aeration in soil to ensure oxygen availability for roots. Cultivate, add grit/sand/perlite.
Open cuttings compost for stem cuttings so that rapidly dividing root cells have plenty of oxygen.

Question 18

How does water affect respiration?

Answer 18

Most biological processes take place in water. Many substances dissolved in water.
Affects activity of enzymes and so areas of very low water eg. seeds have very low respiration rate. If plant is water stressed then stomata close and oxygen does not enter and reduces respiration.
Water logged plants anaerobic respiration takes over. Ethanol can build up and become toxic.
Seeds stored in air tight dry containers so that water uptake and therefore respiration rate is low. Ie. they remain viable for longer.
If soil is regularly waterlogged - plant water loving plants which are adapted to tolerate these conditions.

Question 19

How does carbon dioxide affect rate of respiration?

Answer 19

As carbon dioxide levels increase rate of respiration decreases.
A product of respiration.
Vacuum packed seeds have less O2 and more CO2