VCE Unit 3 & 4 biology



PHOTOSYNTHESIS

Question 1

A plant wilted but later recovered. During the time the leaves were wilted the rate of photosynthesis decreased because:

a) Enzymes in the leaf cells were denatured

b) Chlorophyll in the wilting leaves was broken down

c) The amount of light reaching the plant was reduced

d) The amount of carbon dioxide entering the leaf decreased

Question 2

Chloroplasts:

a) Contain glycogen

b) Are found in all plant cells

c) Are found in some bacterial cells

d) Contain layers of internal membranes

Question 3

The production of organic molecules in a crop is reduced when leaves begin to wilt because:

a) Stomata close preventing the entry of carbon dioxide

b) The chlorophyll of wilting leaves decomposes

c) Flaccid mesophyll cells of a leaf are not capable of photosynthesis

d) Accumulation of carbon dioxide in the leaf inhibits the enzymes required for photosynthesis

Question 4

The chloroplast is the organelle responsible for photosynthesis. In chloroplasts:

a) The light independent reactions require water as the initial reactant.

b) The light independent reactions occur in the inner membrane area

c) The final product of the light depdendent reaction is glucose

d) The light reactions occur in the grana

Question 5

Consider the following diagram that is a summary of an important biochemical process.

[pic]

The product X in this biochemical process is:

a) ADP

b) A polymer

c) An amino acid

d) A monosaccharide

Question 6

A student was asked to identify differences between the overall processes of photosynthesis and aerobic respiration in eukaryotic cells. The student prepared the table below to outline the differences. The only correct comparison is:

| |Photosynthesis |Aerobic respiration |

|A |Exergonic |Endergonic |

|B |All stages occur within chloroplasts |All stages occur within mitochondria |

|C |Electron transport not involved |Electron transport involved |

|D |Uses water as a reactant in the first stage |Forms water as a product in the final stage |

Question 7

The following image shows a portion of an electron photomicrograph of a chloroplast. Light dependent reactions occur in region P and the Calvin cycle reactions occur in region Q.

[pic]

Considering events that occur in a chloroplast during photosynthesis it is reasonable to claim that:

a) Oxygen is an input to the reactions at P

b) Carbon dioxide is an input to reactions at Q

c) Chlorophyll is essential for the reactions that occur at Q

d) ADP produced during the events at P is used by events at Q

Question 8

The oxygen gas produced during photosynthesis is derived from the splitting of:

a) Carbon dioxide

b) Water

c) Light sensitive pigments

d) Chlorophyll A

e) Chlorophyll A, B or a carotenoid pigment

Question 9

Consider an experiment in which wheat plants are exposed to carbon dioxide containing the carbon-14 isotope for 1 hour in the presence of light. Which of the following compounds would you expect to contain the highest amount of carbon-14 after the 1 hour exposure?

a) Proteins

b) Sugars

c) Salts

d) Lipids

e) Nucleic acids

Question 10

Which of the following is not a requirement for photosynthesis?

a) Sunlight

b) Oxygen

c) Carbon dioxide

d) Water

e) Chlorophyll

Question 11

In dry conditions plants close the stomata in their leaves to minimise water loss. This results in a significant decrease in the rate of photosynthesis. What is the primary reason for this reduction in photosynthetic rate?

a) Carbon dioxide, a substrate used in photosynthesis, becomes limiting

b) The enzymes that catalyse the photosynthesis reactions become denatured

c) Light is not able to reach the chlorophyll molecules

d) Glucose builds up to dangerous levels within the leaves

e) No oxygen is able to reach the cells that normally perform photosynthesis

Question 12

Which of the following gases are produced in various parts of plants under normal metabolic conditions?

I Carbon dioxide

II Oxygen

III Hydrogen

a) I only

b) II only

c) III only

d) I and II only

e) I, II and III

SHORT ANSWER QUESTIONS

Question 1

A group of students designed a series of experiments to investigate factors affecting the rate of photosynthesis. The plants were enclosed in clear plastic boxes and kept in the dark for ten minutes. The plants in their boxes were then exposed to light for 10 minutes. The students measured the oxygen concentration in the air surrounding the plants. The results are shown in the graph below.

[pic]

a) Write a balanced chemical equation for the process of photosynthesis

__________________________________________________________________________________

b) By referring to your balanced equation explain why the oxygen concentration in the air surrounding the plants can be used as a measure of the rate of photosynthesis.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

c) Explain why the oxygen concentration in the air surrounding the plants decreased during the first 10 minutes of the experiment.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

Question 2

a) Coral growth is assisted by photosynthesis carried out by the algae living insides its cells. Explain how the products of photosynthesis would benefit the coral.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

b) Many of the coral species that contain algae have large flat surfaces or form tall rod like branches. Explain how these coral shapes would assist photosynthesis

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

Question 3

Photosynthesis and cellular respiration are two biochemical processes that are crucial for the maintenance of life on earth. Photosynthesis takes place in 2 phases – a light dependent phase and a light independent phase. One of the products of the reactions of the light dependent phase takes no further part in the overall process and is sometimes referred to as a waste product. What is this waste product?

__________________________________________________________________________________

b) During the light independent phase of photosynthesis sugars are formed which are later used in respiration. Name the high energy compound produced during cellular respiration of glucose.

__________________________________________________________________________________

Question 4

Although photosynthesis is often summarised by a single equation, in fact the process occurs in two distinct phases; the light phase and another phase called the carbon fixation phase or the light independent phase. These 2 phases can be summarised in diagrammatic form as follows:

[pic]

The diagram shows outputs X and Y.

What is output X and how is it produced?

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

Question 5

The birds nest fern Alocasia marcrohizza usually grows in deeply shaded rainforests and has dark green fronds. Sometimes it is found in open sunny location by roadsides where it tends to have lighter coloured fronds. Two birds nest ferns, one from each of the two habitats described above were examined. A sample of cells from a frond of each of the ferns was collected. The cells were examined under an electron microscope and a typical chloroplast from each habitat was drawn. These drawings are shown below.

[pic]

a) Which of the labelled parts, X, Y or Z absorb light energy? Name the part.

__________________________________________________________________________________

b) Which drawing A or B shows a chloroplast from the rainforest habitat? Explain the reason for your choice in terms of the relationship between structure and function.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

c) Name the process by which the chemical reactants for the light dependent reactions enter a chloroplast.

__________________________________________________________________________________

d) Chloroplasts contain large numbers of ribosomes. Explain the importance of their presence.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

The simplified diagram below summarises the light independent reactions of photosynthesis

[pic]

e) Name reactant Q

__________________________________________________________________________________

f) You will note that during the light independent reactions many energy carrier molecules of NADPH and ATP are used. What is the source of these energy carriers?

__________________________________________________________________________________

g) What is compound P?

_________________________________________________________________________________

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download