Which one of the following elements must be available in sufficient quantity in the water of a pond in at tadpoles are growing?

• Oxygen

• Iodine

• Nitrogen

• Chlorine

The common characteristic properties of plastics are

• durable, good conductor of electricity, non-reactive

• durable, good conductor of heat, non-reactive

• good conductor of heat, light in weight, a good conductor of electricity

• durable, light in weight, non-reactive

Consider the following terms related to cells.

1. Chromosome
2. Gene
3. Nucleolus
4. Ribosome

Out of these, the parts of the nucleus of a cell are

• C and D

• B and C

• A, B, and C

• A and C

Consider the following edible plants

1. Banana
2. Brinjal
3. Lady's finger
4. Pumpkin

Select from these a pair of plants that has two or more than two edible parts.

• C and D

• B and C

• A and D

• A and B

Tartaric acid is found in

1. Lemons
2. Amla
3. Unripe mangoes
4. Grapes

• A and B

• B and C

• C and D

• A and C

Study the following statements about villi (singular villus).

1. They have very thin walls.
2. They are finger-like projections.
3. They have a network of thin and small blood vessels close to the surface.
4. They have small pores through which food can easily pass.

Identify the statements which give the characteristics that enable the villi to absorb the digested food.

• C and D

• B and D

• A, B, and C

• A and B

Select from the following a set of ruminants

• Buffalo, cow, deer

• Cat, buffalo, deer

• Buffalo, cow, dog

• Cow, deer, dog

Consider the following statements about biodiversity.

1. It refers to the total number of individuals of a particular species living in an area.
2. It refers to only the flora and fauna of a particular species in a given area.
3. It refers to the various (variety of) species of flora and fauna present in an area.
4. It is an artificially protected area for animals.

The true statement(s) about biodiversity is/are

• A, B, and C

• Only C

• A, C, and D

• A and B

In human beings, the correct sequence of the events during reproduction is

• zygote, gamete formation, fertilisation, embryo

• gamete formation, fertilisation, zygote, embryo

• gamete formation, zygote, fertilisation, embryo

• gamete formation, fertilisation, embryo, zygote

An object of mass 6 kg is sliding on a frictionless horizontal surface with a uniform speed of 3 m/s. The force required to keep the object moving at the same speed along the same straight line is

• 27 newton

• 18 newton

• 54 newton

• zero newton