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Fungus, moss and fern reproduce by a common method of asexual reproduction. Name the method.

Spore formation The method of asexual reproduction found in fungus, moss and fern is spore formation. The parent plant releases spores into the... View Article

Pollination refers to the (a) transfer of pollen from the anther to the ovary. (b) transfer of male gametes from the anther to stigma. (c) transfer of pollen from the anther to stigma. (d) transfer of pollen from the anther to the ovule.

(c) transfer of pollen from anther to stigma. Pollination is a method where pollen grains are picked from an anther, which is the male part of... View Article

Which of the following statements is/are true for sexual reproduction in plants? (i) Plants are obtained from seeds. (ii) Two plants are always essential. (iii) Fertilisation can occur only after pollination. (iv) Only insects are agents of pollination. Choose from the options given below. (a) (i) and (iii) (b) (i) only (c) (ii) and (iii) (d) (i) and (iv)

a) (i) and (iii) In sexual reproduction, new plants are produced from seeds.Two plants are not always necessary for sexual reproduction. In... View Article

The ovaries of different flowers may contain (a) only one ovule (b) many ovules (c) one to many ovules (d) only two ovules

(c) one to many ovules It is the ductless reproductive gland that holds a lot of ovules. It is the part of the plant where the seed formation... View Article

The ‘eye’ of the potato plant is what (a) the root is to any plant. (b) the bud is to a flower. (c) the bud is to Bryophyllum leaf. (d) the anther is to stamen

c) The bud is to Bryophyllum leaf. The leaves of a Bryophyllum plant have special buds in their margins which may get detached from the leaves,... View Article

Seeds of drumstick and maple are carried to long distances by wind because they possess (a) winged seeds (b) large and hairy seeds (c) long and ridged fruits (d) spiny seeds

a) Winged seeds Seeds of maple and drumstick have wings. The winged seeds help them to travel long distances by wind. Seeds of drumstick and... View Article

Lila observed that a pond with clear water was covered up with green algae within a week. By which method of reproduction did the algae spread so rapidly? (a) Budding (b) Sexual reproduction (c) Fragmentation (d) Pollination

c) Fragmentation An alga breaks up into two or more fragments. These fragments or pieces grow into new individuals. This process continues and... View Article

Which of the following parts of a plant take part in sexual reproduction? (i) Flower (ii) Seed (iii) Fruit (iv) Branch Choose the correct answer from below. (a) (i) and (ii) (b) (i), (ii) and (iii) (c) (iii) and (iv) (d) (ii), (iii) and (iv)

b) (i), (ii) and (iii) Flowers take part in sexual reproduction in plants. Seed forms as a result of the sexual reproduction process. Fruits... View Article

While learning to ride a bicycle Boojho lost his balance and fell. He got bruises on his knees and it started bleeding. However, the bleeding stopped after some time. (a) Why did the bleeding stop? (b) What would be the colour of the wounded area and why? (c) Which type of blood cells is responsible for clotting of blood?

a) Bleeding stopped due to formation of blood clots. b) Dark red due to clotting of blood. c) Platelets are responsible for clotting of blood.... View Article

Fill in the blanks of the following paragraph using just two words – arteries and veins. _(a)_ carry oxygen-rich blood from the heart to all parts of the body and _ (b)_ carry carbon dioxide-rich blood from all parts of the body back to the heart. _ (c)_ have thin walls and (d)_ have thick elastic walls. Blood flows at high pressure in _ (e). Valves are present in (f) _ which allow blood to flow only towards the heart. (g)_ divide into smaller vessels. These vessels further divide into extremely thin tubes called capillaries. The capillaries join up to form (h)___.

Arteries and Veins are two different types of blood vessels in the circulatory system and are mainly involved in circulating blood throughout the... View Article

Read the following terms given below. (Root hairs xylem urethra arteries kidneys veins atria capillaries heart ureter phloem urinary bladder) Group the terms on the basis of the categories given below. (a) The circulatory system of animals. (b) Excretory system in human. (c) Transport of substances in plants.

The terms on the basis of the categories are: a) Arteries, atria, capillaries, veins, heart are the circulatory systems of animals. The human... View Article

Paheli noticed water being pulled up by a motor-pump to an overhead tank of a five-storeyed building. She wondered how water moves up to great heights in the tall trees standing next to the building. Can you tell why?

Roots absorb minerals and water from the soil constantly. The suction force is created by evaporation of water from leaves. It helps water to... View Article

Name the process and the organ which helps in removing the following wastes from the body. (a) Carbon dioxide (b) Undigested food (c) Urine (d) Sweat

Waste Process Organ Carbon dioxide Exhalation Lungs Undigested food Egestion Anus and large intestine Urine Excretion Kidney Sweat... View Article

Boojho’s uncle was hospitalised and put on dialysis after a severe infection in both of his kidneys. (a) What is dialysis? (b) When does it become necessary to take such a treatment?

a) The periodical filtering of blood through artificial kidney is termed as 'Dialysis'. A kidney can filter 100-150 quarts of blood every day. If... View Article

(a) Name the only artery that carries carbon dioxide-rich blood. (b) Why is it called an artery if it does not carry oxygen-rich blood?

(a) The pulmonary artery is the only artery that carries carbon dioxide-rich blood. A pulmonary artery is a set of blood vessels that are related... View Article

Paheli uprooted a rose plant from the soil. Most of the root tips, with root hairs, got left behind in the soil. She planted it in a pot with new soil and watered it regularly. Will the plant grow or die? Give a reason for your answer.

The possible situations could be a) The plant will die because without the root hairs, the root will not able to absorb nutrients and water.... View Article

Arrange the following statements in the correct order in which they occur during the formation and removal of urine in human beings. (a) Ureters carry urine to the urinary bladder. (b) Wastes dissolved in water is filtered out as urine in the kidneys. (c) Urine stored in the urinary bladder is passed out through the urinary opening at the end of the urethra. (d) Blood containing useful and harmful substances reaches the kidneys for filtration. (e) Useful substances are absorbed back into the blood.

The arranged statements are: a) Blood containing useful and harmful substances reaches the kidneys for filtration. b) Useful substances are... View Article

Name the organ which is located in the chest cavity with its lower tip slightly tilted towards the left.

Heart The heart is a blood-pumping organ of the human circulatory system.The human heart is one of the most important organs responsible for... View Article

What is the special feature present in a human heart which does not allow mixing of blood when oxygen-rich and carbon dioxide-rich blood reach the heart?

A septum is a diving wall which is present between the the left side and the right side of the heart, which does not allow mixing of blood when... View Article

Veins have valves which allow blood to flow only in one direction. Arteries do not have valves. Yet the blood flows in one direction only. Can you explain why?

The artery have thick elastic walls and arteries receives blood in high pressure directly from the left ventricle. Because of the high pressure... View Article

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