By4

Front 1

Where does photosynthesis occur and in what cells are these structures present?

Back 1

Chloroplasts located in mesophyll and guard cells.

Front 2

What are examples of chlorophylls and which regions of the spectrum do they absorb?

Back 2

Chlorophyll A and B, they absorb light in the red and blue/violet region.

Front 3

Examples of carotenoids and region of the spectrum they absorb.

Back 3

Carotene and xanthophyll, only blue/violet region.

Front 4

What does the absorption spectrum indicate?

Back 4

Amount of light absorbed at each particular wavelength.

Front 5

What does the action spectrum indicate?

Back 5

The amount of photosynthesis happening at each particular wavelength.

Front 6

Why is it on advantage for a plant to have more than 1 type of pigment?

Back 6

As each pigment absorbs light at different wavelengths, with more pigment, more of the natural light can be utilized,more photosynthesis can take place and the plant will be more efficient.

Front 7

What is the function of the antenna complex?

Back 7

To trap light energy then channel it down to the reaction centre. It contains the carotenoids.

Front 8

What makes up the reaction centre?

Back 8

Chlorophyll A

Front 9

What is the structure of a photo system?

Back 9

Front 10

How do you calculate the Rf value?

Back 10

Front 11

Where does the light stage take place?

Back 11

On the inner thylakoid membrane

Front 12

What happens during the light stage?

Back 12

Light energy is trapped in photosystem II and boosts electrons from the reaction centre to a higher energy level where the electrons are accepted by an electron acceptor on the thylakoid membrane. The electrons are then passed by a series of carriers to photosystem I, the energy lost in this process is captured and converts ADP into ATP. This means light energy has been converted into electrical energy. Light energy is absorbed by photosystem I and this boosts electrons to an even higher energy level where they are accepted by another electron acceptor. The electrons previously lost from the chlorophyll are replaced by electrons from the splitting of water. The protons from the splitting of water combine with NADP to make NADPH which is used in the dark stage. Some of the electrons from the 2nd electron acceptor can pass back to the chlorophyll and this gives ATP only and is called cyclic photo phosphorylation.

Front 13

Define the term immigration

Back 13

Movement of individuals into a population.

Front 14

Define the term emmigration.

Back 14

Permanent movement of individuals out of a population.

Front 15

What is migration?

Back 15

Periodic seasonal movement

Front 16

What are density dependent factors which affect population size?

Back 16

Accumulation of waste, disease, parasitism and possibly food supply.

Front 17

What are density independent factors which affect population size?

Back 17

Usually due to a sudden or extreme change in an abiotic factor such as a fire, flood or freezing.

Front 18

What is a population fluctuation?

Back 18

The numbers of a species lie near an equilibrium point known as a set point which is the specific point that an environment can support. If a population rises above this point, a density dependent factor increases mortality or reduces breeding so population decreases. If it falls below this point, environmental resistance is temporarily relieved so the population rises again.

Front 19

What do plants compete for?

Back 19

Light, space, water and nutrients

Front 20

What do animals compete for?

Back 20

Food, shelter, space and reproductive partners.

Front 21

What is intraspecific competition?

Back 21

Competition between individuals of the same species.

Front 22

What is interspecific competition?

Back 22

Competition between individuals of different species. In the long term, 2 species cannot occupy the same niche in a specific habitat.

Front 23

What is a pest?

Back 23

Something that feeds on crops and animals, competes with crops for resources, causes disease in crops, make infection by pathogens more likely and can spoil food when stored or transported.

Front 24

What is chemical control?

Back 24

The use of poisonous chemicals to control organisms considered harmful to agriculture or organisms involved in disease transmission. e.g. herbicides, fungicides and insecticides.

Front 25

What are the advantages of chemical control?

Back 25

effective, eradicate pests relatively quickly and cheaply, can be applied on a small scale and application does not require high levels of ...

Front 26

What are the disadvantages of chemical control?

Back 26

Not specific so can eradicate beneficial insects such as bees or biological control agents, pests may become resistant, some pesticides may kill mammals, birds, fish by contaminating their food and long term exposure can harm humans.

Front 27

What is biological control?

Back 27

The exploitation of predator-prey relationships by humans.

Front 28

Why is it not wise to eradicate the pest completely with biological control?

Back 28

There would be no food for the predator which would die out, then pest may reemerge later with no predators.

Front 29

What is the most successful form of biological control and why?

Back 29

When native predators or parasites have been used because sometimes non-native predators have become a pest themselves.

Front 30

What are the advantages of biological control?

Back 30

Usually specific to one pest, long term control if population equilibrium established, in the long term inexpensive, there is no environmental contamination and can be used in glass houses.