List of practice Questions

Which one of the following can be used as an acid-base indicator by a visually impaired (blind) student?

The hydrocarbons with general formula \( C_nH_{2n} \) represents:

When an element 'X' reacts with water, it starts floating. Identify the element 'X':

Which of the following is a poor conductor of electricity?

The natural sources of oxalic acid, lactic acid and methanoic acid respectively are:

Given below are certain situations. Analyse each and describe its possible impact:
(i) A population of bacteria living in temperate waters whose temperature increased by global warming.
(ii) The sperm encounters the egg when it reaches the oviduct in human females.
(iii) Self pollination does not occur in a flower that contains only pistil.
(iv) Egg does not get fertilised in a human female.
(v) When the seed is placed under appropriate condition of water and air in the soil?

Given below are certain situations. Analyse and describe what would happen when:
(i) Spores are liberated from blob-like structures of the bread mould?
(ii) Leaves of bryophyllum fall on wet soil?
(iii) A pollen from different species land on the stigma of totally unrelated species?
(iv) Copper-T is placed in the uterus of a human female?
(v) Spirogyra breaks into smaller fragments upon maturation?

The gases evolved on heating lead (II) nitrate crystals are :

(i) \( \text{AgNO}_3 + \text{NaCl} \rightarrow \text{NaNO}_3 + \text{AgCl} \)
(ii) \( \text{K}_2\text{SO}_4 + \text{BaCl}_2 \rightarrow \text{BaSO}_4 + 2\text{KCl} \)
Which of the following options clearly describes both the reactions?

(a) Why is bile juice considered to be very important for digestion, even though it doesn't contain any digestive enzymes?
(b) Name some substances present in initial filtrate and subsequently selectively reabsorbed in the tubules of nephron.

Draw a neat diagram to show germination of pollen on the female reproductive part of the flower. Name and label only the following parts:
(a) The part that receives the pollen grain.
(b) The structure that carries the male germ cell to reach the female germ cell.

State two differences between the act of chewing food and salivation on sight of food.

State two differences between pollination and fertilization.

Give differences between the following :
(a) Nephron and neuron
(b) Sensory nerve and motor nerve
(c) Consumers and decomposers

Given below is a pyramid showing various trophic levels in an ecosystem:

(a) From the organisms listed below, identify which one is to be placed at which trophic level:
Deer, Grass, Lion, Snake, Rabbit
(b) Discuss the reason why primary consumers will have more energy as compared to secondary consumers?
(c) Why is the base of the pyramid broad?

Study the given diagram of the heart, with blood vessels marked '1' and '2'.
From the following statements, establish the relationship between heart and/or the two blood vessels:
(i) Blood vessel 1 - It carries carbon dioxide rich blood to the lungs.
(ii) Blood vessel 2 - It carries oxygen rich blood from the lungs.
(iii) Blood vessel 2 - Left atrium relaxes as it receives blood from this blood vessel.
(iv) Blood vessel 1 - Right atrium has thick wall as it has to pump blood to this vessel.

The option with correct statements is:

Plants use variety of techniques to get rid of their waste materials. Some are mentioned below. Identify the incorrect one:

Assertion (A): Reflex actions do not involve thinking.
Reason (R): Most reflex actions are controlled by the spinal cord.

Assertion (A): Ozone at higher levels of atmosphere is a product of UV radiation acting on oxygen molecule.
Reason (R): The higher energy of UV splits apart some molecular \( O_2 \).

Which structure in a leaf is mainly responsible for gaseous exchange?

Pancreas secretes pancreatic juice which contain enzyme that helps in digestion of food. Choose the correct option from the following:

From the given situations, identify 'Chemotropic' and 'Geotropic' movements in parts of plants, respectively:
(i) Growth of pollen tube towards ovule.
(ii) Movement of sunflower towards sunlight.
(iii) Movement of root towards Earth/Gravity.
(iv) Movement of leaves due to breeze.

Which of the following group is not 'biodegradable'?

Identify the correct statement for spirogyra, leishmania and hydra