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Flashcards in B8 Photosynthesis Deck (40)
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1
Q

Is photosynthesis an endothermic or exothermic reaction?

A

Endothermic

2
Q

What is Photosynthesis?

A

Photosynthesis is a chemical reaction that takes place inside a plant, producing food for the plant to survive.

3
Q

What is needed for Photosynthesis?

A

Carbon dioxide, water and light are all needed for photosynthesis to take place.

4
Q

What is the word equation for photosynthesis?

A

Carbon Dioxide + Water + (light over the arrow) -> glucose +oxygen

5
Q

What is the symbol equation for Photosynthesis?

A

6CO2 + 6H20 +(light over the arrow)-> C6H12O6 + 6O2

6
Q

How can you see oxygen being produced when a plant is photosynthesising?

A

If you use Water plants such as Pom weed or Elodea you can see and collect the bubbles of gas they give of when photosynthesising.

7
Q

How are leaves of plants adapted for photosynthesising?

A
  • Most leaves have a big surface area for light to fall on.
  • Most leaves are thin so diffusion distance for the gases are short
  • Contain chlorophyll in the chloroplasts to absorb light
  • They have veins , which bring plenty of water in the xylem to the cells of the leaves and remove products of photosynthesis in the pholem.
  • Air spaces that allow Carbon dioxide to get to the cells, and oxygen to leave by diffusion
  • They have guard cells that open and close the stomata to regulate gas exchange.
8
Q

What happens during photosynthesis?

A

_During photosynthesis energy is transferred from the environment to the chloroplast by light.

  • It is used to convert carbon dioxide and water into sugar (glucose).
  • Oxygen is also formed and released as by product
9
Q

What are the limiting factors for photosynthesis?

A
  • Temperature
  • Light
  • Carbon dioxide concentration
  • Chlorophyll levels in the leaf
10
Q

How is temperature a limiting factor for photosynthesis?

A

As temperature rises, the rate of photosynthesis increases as the reaction speeds up. However enzymes are denatured once the temperature rises around 40-50°C.

11
Q

What happens to the rate of photosynthesis if the temperature gets too high?

A

if the temperature gets to high , the enzymes controlling photosynthesis are denatured and the rate of photosynthesis will fall.

12
Q

How is light a limiting factor for photosynthesis?

A

If there is plenty of light , lots of photosynthesis can take place. If there is little or no light , photosynthesis will stop.

13
Q

What is the correlation for light and photosynthesis?

A

For most plants, the brighter the light, the faster the rate of photosynthesis.

14
Q

how is Carbon Dioxide limiting factors for photosynthesis?

A

At lower carbon dioxide concentrations carbon dioxide is the limiting factor because an increase in carbon dioxide causes an increase in photosynthesis.

15
Q

What is the correlation for Carbon Dioxide and photosynthesis?

A

As carbon dioxide concentrations increase, so too does the rate of photosynthesis until a certain point where the graph levels off

16
Q

How is chlorophyll levels in the leaf a limiting factor for photosynthesis?

A

If the amount of chlorophyll in a leaf is limited in any way less photosynthesis will take place

17
Q

What are the control variables the light intensity and rate of photosynthesis practical

A

The control variables are:

  • the same Piece of pondweed
  • temperature using beaker of water
18
Q

What are the safety considerations for the light intensity and rate of photosynthesis practical?

A
  • Keep electrical equipment dry
  • Heat from lamp
  • Careful with glass
19
Q

What is light intensity and the inverse square law?

A

The light energy at twice the distance away is spread over four times the area. The light energy at three times the distance away and is spread over nine times the area and so on. The light intensity is inversely proportional to the square of the distance this is the inverse square law.

20
Q

What is the equation for Light intensity?

A

Light intensity (inverse symbol) 1/d^2

21
Q

How do plants use glucose?

A

The glucose is broken down using oxygen to provide energy for the cells.

  • For cell walls
  • To be stored
22
Q

What are the waste products of photosynthesis?

A

Carbon dioxide and Water

23
Q

Why do plants build up glucose?

A

Plant build up glucose into complex carbohydrates such as cellulose. they use this strengthens the cell walls.

24
Q

What happens if glucose was stored in plant cells?

A

If it was stored in plant cells it could affect the way water moves into and out of the cells by osmosis.

25
Q

Is Glucose soluble or insoluble in water?

A

Glucose is soluble in water. Lots of glucose is stored in plant cells could affect the water balance of the whole plant.

26
Q

Is Starch insoluble or soluble in water?

A

Starch is insoluble in water. It has no effect on the water balance of the plant so plants can store large amount of starch in their cell walls.

27
Q

Why is starch stored in the cells of the leaves?

A

Starch is stored in the cells of the leaves.It provides an energy store for when it is dark or when Light levels are low.

28
Q

Where else is starch stored?

A

Starch is also kept in special storage areas of the a plant.
For example many plants produce tubers and bulbs that are full of stored starch to help them survive for the winter

29
Q

How are amino acids made and used

A

Glucose is used to make amino acids to build up proteins to be used in plant cells in many ways including enzymes. the energy is used for respiration

30
Q

How are lipids made and used?

A

Glucose is used to make lipids to use as energy stores.

  • energy is used for respiration
  • used in cells to make stronger
  • and seeds are created to provide new food for new plants
31
Q

How do you plant and algal cells use glucose?

A

Plant and Agal cells use the Glucose produced during photosynthesis respiration to:

  • convert into insoluble starch for storage
  • to produce fat or oils for storage
  • to produce cellulose to strengthen cell walls
  • and to produce Amino acid for protein synthesis
32
Q

Why do plants and algal cells need nitrate ions?

A

Plants and alcohol cells also need nitrate ions absorbed from the soil or water to make the amino acids used to make proteins

33
Q

Why are limiting factors important in greenhouses?

A

Limiting factors are important in the economics of enhancing the conditions in the greenhouses to gain the maximum rate of photosynthesis whilst still maintaining profit.

34
Q

Why is a greenhouse a good storage facility to increase light intensity for crops?

A

Maximising the light transmission which can speed up the rate of photosynthesis

35
Q

What process do the fungi do to increase the concentration of carbon dioxide in the greenhouse?

A

Fungi respire and release carbon dioxide into the environment

36
Q

In what layer of the leaf does photosynthesis take place?

A

Palisade layer

37
Q

Which organelle in plant cells produce chlorophyll?

A

Chloroplasts

38
Q

In what layer of the leaf does most photosynthesis take place?

A

Palisade mesophyll layer

39
Q

How are water levels controlled in the plant?

A

By the guard cells that open and close the stomata

40
Q

Why are there air spaces in the spongy mesophyll layer?

A

For faster exchange of gases