INTERACTIVE MULTIPLE CHOICE QUESTIONS Test 2

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INTERACTIVE MULTIPLE CHOICE QUESTIONS Test 2 The answers are provided, but so also are explanations of why the alternatives are unsatisfactory

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Page 1: INTERACTIVE MULTIPLE        CHOICE QUESTIONS Test 2

INTERACTIVE MULTIPLE CHOICE QUESTIONS

Test 2

The answers are provided, but so also are explanations of why the alternatives are unsatisfactory

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Question 1

These multiple choice questions are similar to the ones set by the GCSE and IGCSE Examination Boards except that, in some cases, there may be more than one acceptable answer.

For this reason, even if you select a correct answer at your first attempt, it is worth looking at all the alternatives (a) to see if there is a better answer and (b) to see why some of the alternatives are unacceptable.

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Question 1

A male heterozygous black mouse (Bb) is mated with a female heterozygous black mouse (Bb) and the litter consists of 12 pups. B is the allele for the black colour. The allele for brown colour is b. The dominant allele is B . Which of these ratios is closest to the expected ratio for the distribution of colour among the offspring?

(d) 8 black and 4 brown

(c) 4 black and 8 brown

(b) 6 black and 6 brown

(a) all black

Question 2

X

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B

B b

b

BB Bb

Bb bb

gametes

From the Punnett square you can see that the expected ratio is 3 black (BB or Bb) to 1 brown (bb)

These are only the chance combinations. It would be possible to produce 12 black pups, since ‘black’ is the dominant allele but this is not close to the expected ratio

Not very close

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B b

b

BB Bb

Bb bb

gametes

B

From the Punnett square you can see that the expected ratio is 3 black (BB or Bb) to 1 brown (bb)

These are only the chance combinations. It would be possible to produce 6 black and 6 brown pups but this is not very close to the expected ratio of 9:3

Not very close

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B b

b

BB Bb

Bb bb

gametes

B

From the Punnett square you can see that the expected ratio is 3 black (BB or Bb) to 1 brown (bb)

These are only the chance combinations. A combination of 4 black to 8 brown is close to the expected ratio of 3:9 but since black is the dominant allele it seems to be the wrong way round

Close but ….

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B b

b

BB Bb

Bb bb

gametes

B

From the Punnett square you can see that the expected ratio is 3 black (BB or Bb) to 1 brown (bb)

These are only the chance combinations. A combination of 8 black to 4 brown is closest to the expected ratio of 9:3 so this would be the most likely outcome

The closest

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Question 2

Which of the following gases are the cause of acid rain?

(c) Nitrogen oxide

(b) Carbon monoxide

(d) Sulphur dioxide

(a) Carbon dioxide

Question 3

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Carbon dioxide does dissolve in rain to form a weak solution of carbonic acid (H2CO3) but this is normal and does not contribute to what is known as ‘acid rain’.

However it is thought to be making the ocean more acid and this is a cause for concern

No

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Carbon monoxide is a poisonous gas but does not contribute to acid rain

No

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Oxides of nitrogen dissolve in rain water to form nitric acid which is very harmful to lakes and land plants

Yes

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Sulphur dioxide dissolves in water to form, eventually, sulphuric acid. This damages lakes and land plants

Yes

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Question 3

Asexual reproduction in plants

(d) disperses the offspring widely

(c) produces variation in the offspring

(b) maintains the characteristics of the plant

(a) involves self-fertilisation

Question 4

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Self-fertilisation is one type of sexual reproduction

No

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Asexual reproduction does maintain the parental characteristics in all the offspring. This is particularly valuable in horticulture for retaining the desirable characteristics of a plant.

Yes

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Asexual reproduction does not result in variation among the offspring

No

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Asexual reproduction does not result in dispersal. Plants produced by asexual reproduction usually grow in clumps or colonies

No

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Question 4

A mother’s blood group is A. The father’s blood group is AB. Which of the following blood groups could appear in their children?

(d) O

(c) AB

(b) B

(a) A

Question 5

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The mother’s genotype could be IaIa or IaIo

The father’s genotype can only be IaIb

Their child’s genome could therefore include IaIa, IaIo, IaIb or IbIo

The first two of these would be expressed as group A because Ia is dominant to Io

Yes

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The mother’s genotype could be IaIa or IaIo

The father’s genotype can only be IaIb

Their child’s genome could therefore include IaIa, IaIo, IaIb or IbIo

IbIo would be expressed as group B because Ib is dominant to Io

Yes

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Yes

The mother’s genotype could be IaIa or IaIo

The father’s genotype can only be IaIb

Their child’s genome could therefore include IaIa, IaIo, IaIb or IbIo

In the the combination IaIb the alleles are codominant and would be expressed as group AB

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No

The mother’s genotype could be IaIa or IaIo

The father’s genotype can only be IaIb

Their child’s genome could therefore include IaIa, IaIo, IaIb or IbIo

The combination IoIo could not arise

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Question 5

Ranunculus bulbosus is

(d) A family

(c) A class

(b) A species

(a) A genus

Question 6

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The genus is Ranunculus. This is the genus which includes the buttercups

No

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The use of the binomial name indicates that Ranunculus bulbosus is a species (the bulbous buttercup).

Yes

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The class would be flowering plants

No

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The family would be Ranunculaceae which includes clematis, anemone, water lily as well as buttercup.

No

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Question 6

Sunflower seedlings with straight shoots are placed on a window sill. After a period of several hours, the growing parts of the stems have turned through 30o and are now growing towards the window. This is an example of

(d) positive geotropism

(c) positive phototropism

(b) negative phototropism

(a) a response to a stimulus

Question 7

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This is certainly a response (growth movement) to a stimulus (light from one side) but it is possible to be more precise

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Negative phototropism implies a growth movement away from the light source

No

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This is an example of positive phototropism, a growth movement (response) towards the light source (the stimulus)

Yes

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Geotropism refers to a response to gravity acting on one side of the plant.

No

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Question 7

Question 8

Which of these processes increase the concentration of carbon dioxide in the atmosphere?

(a) Respiration

(b) Photosynthesis

(c) Combustion

(d) Decay

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Aerobic respiration involves the oxidation of carbohydrates with the production of carbon dioxide.

For example

C6H12O6 + 6O2 6CO2 + 6H2O

Anaerobic respiration involves the breakdown of carbohydrates with the production of carbon dioxide and products such as alcohol or pyruvic and lactic acids.

Yes

For example

C6H12O6 2CO2 + 2C2H5OHalcohol

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No

Photosynthesis removes carbon dioxide from the atmosphere.

6CO2 + 6H2O C6H12O6 + 6O2

glucose

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Yes

When carbon-containing substances burn, the carbon combines with oxygen to produce carbon dioxide

C + O2 CO2

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Yes

Organic compounds all contain carbon. When these decay, they release carbon dioxide. (In the absence of oxygen, decay may result in the production of methane).

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Question 8

In the growth of a plant cell, what causes the cell to increase in size?

(a) Expansion of the vacuole

(b) Division of the nucleus

(c) Formation of a new cell wall

(d) Increase in the amount of cytoplasm

Question 9

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Yes.

The vacuole absorbs water by osmosis and pushes the cell wall outwards while it is still plastic

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No

Division of the nucleus precedes cell division but does not increase the size of cells

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No

A new cell wall is formed before cell expansion takes place, but the cell wall remains plastic till expansion is complete

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No

In the course of cell division, new cytoplasm is formed but this precedes any cell enlargement.

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Question 9

Which of these alternatives is the correct sequence of events when we breathe in?

(a) The lungs fill with air and push down the diaphragm and expand the rib cage.

(b) Muscles pull the ribs upwards and outwards and cause the lungs to expand

(c) The diaphragm is lowered, the ribs are pulled downwards and air is drawn into the lungs

(d) The diaphragm is lowered, the rib cage is expanded and air is drawn into the lungs.

Question 10

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No

Air cannot enter the lungs unless they are first made to expand

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Partly right

The movement of the rib cage does draw air into the lungs but this is not the main force responsible

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No.

If the ribs are pulled downwards, this will reduce the volume of the thorax and counteract the effect of the diaphragm

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Yes

These two movements increase the volume of the thorax and cause air to be drawn into the lungs.

The rib movements do not usually come into play except for deep breathing as in taking exercise.

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Question 10

In the process of active transport, substances move into a cell

(a) by osmosis

(b) by simple diffusion

(d) down a diffusion gradient

(c) against a diffusion gradient

Question 11

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No

Osmosis refers only to the diffusion of water

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No.

Substances can enter the cell by diffusion but this is not active transport

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Yes

Active transport enables a cell to take up substances against a diffusion gradient. This requires the expenditure of energy.

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No

Substances could enter a cell by diffusion down a diffusion gradient but this is not active transport

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Question 11

Tooth decay is caused principally by

(a) plaque

(d) sugar

(c) bacterial activity

(b) failure to brush the teeth regularly

Question 12

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Plaque is a coating which forms round the teeth. It contains bacteria but the plaque itself is not responsible for tooth decay

No

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Regular brushing does help to remove plaque and the bacteria it contains, but failure to brush regularly is not itself a cause of decay.

The principal value of brushing is the prevention of gum disease.

No

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Yes.

The bacteria flourishing in the plaque release acids which cause the cavities in the teeth

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The bacteria on the tooth surface metabolise sugar and produce the acids which cause cavities, but sugar itself is not a cause of decay.

No

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Question 12

The cell labelled A is best described as

Section through a leaf

A1mm

(d) an epidermal cell

(c) a palisade cell

(b) a mesophyll cell

(a) a leaf cell

Question 13

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Cell A is certainly a leaf cell but this is not a precise enough description

No

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Cell A is a mesophyll cell but so are all the cells enclosed by the upper and lower epidermis (except for the vascular tissue). This is not a precise enough description

Yes but ….

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Yes

Cell A is a palisade cell, or better still, a ‘palisade mesophyll cell’. Most of the photosynthesis in the leaf takes place in these cells.

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No

The epidermal cells form the outer layers of the leaf

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Question 13

Acute shortage of oxygen in lakes and rivers is caused by

(d) excessive growth of algae

(c) excess nitrate and phosphate

(b) the oxygen demand by the excess of decaying plant material

(a) eutrophication

Question 14

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Eutrophication refers to a high level of nutrients in a body of water. It may cause excessive algal growth but is not a direct cause of oxygen depletion

No

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Yes

The oxygen demand of an excess of decomposing plant material, e.g. algae, is the immediate cause of the reduction in the oxygen content of the water in lakes and rivers.

The excess of plant material is the result of eutrophication

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Eutrophication results from high levels of nitrate and phosphate in the water. But although this encourages excessive algal growth it does not inevitably lead to oxygen depletion.

No

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The excessive growth of algae is not itself a cause of oxygen depletion.

No

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Question 14

Which of the following statements are correct? In moving through each trophic level in a food chain e.g. producers 1st order consumers 2nd order consumers etc

(a) the number of organisms increases

(b) energy is lost

(c) the number of organisms is reduced

(d) plants are eaten by animals

Question 15

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No

In many cases the number of organisms at each level decreases

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Yes

At each trophic level, the organisms lose energy as a result of their living processes. This means that less energy is available to the next trophic level

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Partly correct

The number of organisms at each trophic level usually decreases but there are exceptions. For example a single oak tree may support a population of hundreds of caterpillars.

It is the total biomass which decreases.

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No

At the first trophic level plants may be eaten by animals but at succesive levels it is a case of animals eating animals, e.g. barn owls eating voles.

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Question 15

A student sets up this experiment to investigate whether germinating seeds take up oxygen. The experiment is inadequately designed because

germinating seeds

soda-lime

(d) the volume of O2 taken up will be the same as the volume of CO2 given out

(c) there is no temperature control

(b) there are not enough seeds

(a) there is no control experiment

Question 16

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This is a serious fault in the design. There should be an identical experiment with dead seedlings to establish that any oxygen uptake is the result of a living process in the seedlings

Yes

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The student might get quicker results if there were more seedlings but this is not a fault in the experimental design

No

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Without a any form of temperature control the apparatus will behave like an air thermometer. Any change in the temperature will cause the air in the flask to expand or contract and affect the level of the liquid in the delivery tube

If the flask was in a container of water, temperature fluctuations would be very much reduced

Yes

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The volume of carbon dioxide given off will be the same as the volume of oxygen taken up but the soda lime absorbs the carbon dioxide.

No

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Question 16

The composition of blood leaving the kidney will differ from that entering the kidney by having

(d) less oxygen, more carbon dioxide, more glucose, less salt and urea

(c) more oxygen, less carbon dioxide, less salt and urea

(b) less oxygen, more carbon dioxide, less salt and urea

(a) less oxygen, more carbon dioxide, more salt and urea

Question 17

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No

Respiration in the kidneys will use oxygen and produce carbon dioxide but urea and salt are removed by the kidneys

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Yes

Respiration in the kidneys uses oxygen and produces carbon dioxide. The energy released is used to remove urea and excess salt

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No

Respiration in the kidneys reduces the oxygen concentration in the blood and increases the carbon dioxide concentration

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No

This is mainly correct but the glucose concentration will not be increased in blood leaving the kidney. In fact it is likely to be reduced as a result of respiration

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Question 17

For photosynthesis to take place, a green plant needs

(d) Carbon dioxide, chlorophyll and water

(b) Carbon dioxide, water, chlorophyll and minerals

(a) Carbon dioxide, water, chlorophyll and sunlight

(c) Carbon dioxide, oxygen, chlorophyll and water

Question 18

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Yes

All these are needed for photosynthesis to take place

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No

Sunlight is needed for photosynthesis.

Minerals are not needed for photosynthesis itself but are used to help convert the glucose into other products

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Oxygen is not needed for photosynthesis. Photosynthesis produces oxygen

Sunlight, however, is needed

No

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Sunlight is needed for photosynthesis to take place

No

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Question 18

Which of the following compounds would you classify as an enzyme?

(d) Calciferol

(c) Adenine

(b) Sucrase

(a) Sucrose

Question 19

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No

The –ose ending tells you that the compound is a sugar

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Yes

The –ase ending indicates that the compound is an enzyme.

This enzyme. sucrase, acts on sucrose and converts it to glucose and fructose

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No

Adenine is an organic base. It occurs in DNA and RNA and a number of other compounds. It is not an enzyme

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No

Calciferol is Vitamin D. It is not an enzyme

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Question 19

Which of the following are good sources of protein?

(d) Potato

(c) Baked beans

(b) Banana

(a) Herring

Question 20

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Yes.

Herring are an excellent source of protein having 16g protein per 100 g fish.

They are also a valuable source of unsaturated fats and vitamin E

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No

Bananas have only 1g protein per 100g fruit. They provide mainly carbohydrate

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Yes

Though not as good as herring, baked beans in tomato sauce provide 6g protein per 100g beans

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No

Potatoes provide mainly carbohydrate in the form of starch. They contain only 1.4g protein per 100g potato

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Question 20

In the nitrogen cycle, the bacteria which can convert nitrogen in the air into nitrates are called

(d) nitrogen-fixing bacteria

(c) nitrite bacteria

(b) denitrifying bacteria

(a) nitrate bacteria

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No

Nitrate bacteria convert nitrites in the soil to nitrates

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No

Denitrifying bacteria break down nitrates in the soil and release atmospheric nitrogen

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Nitrite bacteria convert ammonium compounds to nitrites

No

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Yes

Nitrogen-fixing bacteria can use nitrogen in the air to produce nitrates. These bacteria are found mostly in the root nodules of plants of the pea and bean family (leguminous plants)

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