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Flashcards in Life Processes Deck (50)
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1
Q

Define photosynthesis

A

Photosynthesis is the process by which plants use sunlight to produce glucose for cellular respiration

2
Q

What is the equation for photosynthesis

A

carbon dioxide + water + sunglight –> oxygen + glucose

3
Q

Where does the light-dependent reaction take place

A

Thylakoid membrane within the chloroplast

4
Q

Where does the light-independent reaction take place

A

Stroma of the chloroplast

5
Q

How is light energy absorbed

A

Light energy is absorbed by the pigment chlorophyll in the chloroplasts. This light energy splits the water molecule into hydrogen & oxygen

6
Q

Where is carbon dioxide absorbed

A

Stomata

7
Q

Where is water absorbed

A

Plant roots

8
Q

Do shade plants have bigger chloroplasts, if so why or why not?

A

Shade plants have bigger chloroplasts, so they can photosynthesis sufficiently due to increased surface area

9
Q

Do non-shaded plants have bigger chloroplasts, if so why or why not?

A

Non-shaded plants do not need bigger chloroplasts as they already have enough light energy

10
Q

Describe & explain the effect if enough water is not provided

A

Water is required for photosynthesis, so if enough water is not provided, the reaction slows down & does not have enough energy needed for other life processes such as cellular respiration. The plant will not be able to perform the reaction & will wilt & die

11
Q

Describe & explain the effect if the amount of water is increased

A

If there is an increased amount of water, the reaction will increase to a certain limit, after a further increase will no longer affect the rate. Due to an increase, the limiting factors would also need to increase to bring a further increase in the rate

12
Q

Describe & explain how different intensities of light provide different amounts of energy

A

If there is low light, the chloroplasts will move in order to get more light, ensuring that the maximum surface area faces the light.
If there is too much light, it can damage the chloroplast, so the chloroplasts will move to reduce this light exposure

13
Q

Describe & explain the effect temperature has

A

If the temperature is surrounding the plant is warm, the enzymes will collide with more substrates, increasing the frequency of collisions and a faster rate of photosynthesis
However, if the temperature is too hot, the enzymes will denature, resulting in the active site changing its shape, in which case the reaction would stop

14
Q

Define cell respiration

A

Cell respiration is the process by which organisms obtain energy from organic molecules such as fat, sugar & protein needed for cellular life processes

15
Q

What is the purpose of cell respiration

A

The purpose of cell respiration is to the provide cells with enough energy needed to function

16
Q

What is the equation for cell respiration

A

glucose + oxygen –> carbon dioxide + water + energy

17
Q

Where does aerobic respiration occur

A

Mitochondria

18
Q

Define aerobic respiration

A

Respiration using oxygen to break down food molecules

19
Q

Define anaerobic respiration

A

Respiration without using oxygen to break down food molecules

20
Q

Where does anaerobic respiration occur

A

cytoplasm of an animal cell

21
Q

Is anaerobic respiration more efficient or aerobic respiration

A

Aerobic respiration

22
Q

Why is aerobic respiration more efficient

A

Aerobic respiration is more efficient as it produces more ATP energy, due to the oxygen present. However, ATP energy is produced more slowly as it uses oxygen.

23
Q

Why is anaerobic respiration less efficient

A

Anaerobic respiration is less efficient as it produces less ATP energy, due to lack of oxygen. However, ATP energy is produced more quickly as it does not require oxygen.

24
Q

List an advantage of aerobic respiration

A

Lactic acid which is a toxic is not produced

25
Q

List an advantage of anaerobic respiration

A

If the oxygen levels are low, the cells are still able to receive the energy needed to continue functioning, do the body does not shut down

26
Q

List a disadvantage of anerobic respiration

A

Lactic acid is produced which causes cramps & stops muscles from working, it can become toxic if not removed from the body

27
Q

List the similarities between photosynthesis & cell respiration

A

They are opposite reaction of each other, so they use the same molecules of glucose, carbon dioxide, oxygen & water
They both require enzymes

28
Q

List the differences between photosynthesis & cell respiration

A

Cell respiration does not require sunlight
Photosynthesis only occurs in the presence of sunlight
Carbon dioxide & water are absorbed in cell respiration but released in photosynthesis
Photosynthesis requires chlorophyll so can only occur in plants & cell respiration only occurs in animals

29
Q

Define active transport

A

Active transport is the movement of substances across a membrane against a concentration gradient from low concentration to high concentration

30
Q

Does active transport require energy

A

Yes

31
Q

Where does active transport occur

A

through the proteins in the cell membrane

32
Q

Define osmosis

A

Osmosis is the diffusion of water across a semi-permeable membrane from an area of high concentration to low concentration

33
Q

Does osmosis require energy

A

No

34
Q

Give an example of osmosis

A

The water in the soil which has a high concentration is absorbed by tiny root hairs & moves to the root cell semi-permeable membrane and into the root cell which has a low concentration of water

35
Q

Define diffusion

A

Diffusion is the movement of a substance from high concentration to low concentration. A concentration gradient exists until the diffused substance is evenly distributed

36
Q

Does diffusion require energy

A

No

37
Q

Where does diffusion occur

A

Cell membrane; which controls the entry and exit of materials into and out of the cell

38
Q

Discuss the effect of diffusion in regards to the surface area

A

As the cell grows large, SA : V decreases
Due to the decrease in surface area, it would decrease the movement of materials into & out of the cell
If the cell volume grows too large, the transport of substances within the cell will be inefficient, do the cell divides to keep high SA : V

39
Q

What is the purpose of mitosis

A

For growth & repair

40
Q

Discuss the process of mitosis

A

DNA & chromosomes replicate, where the replicated chromosomes condense & move to the equator of the cell where spindle fibres attach to the centromere. One cell then splits to form two identical daughter cells.

41
Q

Why does the cell divide in mitosis

A

To maintain large SA : V ratio

42
Q

Where does mitosis occur

A

Somatic cells

43
Q

Define DNA replication

A

To replicate cells DNA in preparation for cell division

44
Q

What happens to the replicated DNA

A

Replicated DNA is passed on to the daughter cells, ensuring that each daughter cell carries out the same function as the parent cell

45
Q

Discuss the role of enzymes in DNA replication

A

Enzymes are catalysts that speed up reactions by lowering the activation energy. It has an active site, which joins of breaks substrate. DNA replication is dependent on the factors affecting enzyme activity.

46
Q

Discuss how the temperature effects DNA rate of reaction

A

If there is a low temperature, the enzyme action slows down, which means the enzyme collision decreases, which slows the rate of mitosis/cell respiration/meiosis
If there is a very high temperature, the enzyme denatures becoming inactive and decreasing the rate of mitosis/cell respiration/meiosis

47
Q

Discuss how the enzyme/substrate concentration affects the rate of reaction

A

If there is an increase in the substrate concentration, it increases the rate of reaction as more substrates can combine with the enzymes active site

48
Q

Discuss how the pH range affects the rate of reaction

A

If it is outside its optimum pH range, it can cause the enzyme’s active site to denature, preventing the substrate from binding

49
Q

Discuss how the co-enzyme affects the rate of reaction

A

A co-enzyme alters the shape of an active site so it can effectively combine with the substrate
Decreasing the co-enzymes will reduce the rate of reaction or stop the enzyme altogether

50
Q

Define inhibitiors

A

Inhibitors are posions that alter or block the active site, preventing the subtrate from binding