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Amoeba is a ___________ celled organism. It reproduces by ___________ reproduction. The process of reproduction begins by the division of its ___________ into two. This is followed by the division of its ___________ into two. This type of reproduction is called ___________ fission. Fill up the blanks with the terms: (body. asexual, binary, single, nucleus)

Amoeba is a single celled organism. It reproduces by asexual reproduction. The process of reproduction begins by the division of... View Article

Given below are events that lead to pregnancy and development of the embryo. i) Fertilization of egg ii) Maturation of egg iii) Release of egg iv) Embedding of the embryo in the thickened uterine wall. Which of the following options gives the correct order of sequence in which they occur? (a) i, ii, iii, iv, (b) ii, i, iii, iv (c) i, iv, ii, iii (d) ii, iii, i, iv

d) ii, iii, i, iv The sequence of events is as follows: 1. Maturation of egg after puberty. 2. Release of the egg cell. 3. Fertilization of the... View Article

Read the statements given below. (i) Seeds require moisture for germination. (ii) Plants can absorb nutrients mostly in dissolved form. (iii) Irrigation protects crops from both frost and hot air currents. (iv) Irrigation improves soil texture. Choose the combination of statements which indicate the need to irrigate crops. (a) i and ii (b) i, ii, iii (c) i, ii, iii, iv (d) i and iii

(a) i and ii Irrigation is necessary because water is required for germination of seeds. It is the supply of water to crops at regular intervals,... View Article

Which of the following statements are true about the brain? (i) The main thinking part of the brain is the hindbrain (ii) Centres of hearing, smell, memory, sight etc are located in forebrain. (iii) Involuntary actions like salivation, vomiting, blood pressure are controlled by the medulla in the hindbrain (iv) Cerebellum does not control the posture and balance of the body (a) (i) and (ii) (b) (i), (ii) and (iii) (c) (ii) and (iii) (d) (iii) and (iv)

c) (ii) and (iii) On average, an adult brain weighs between 1.0 kg – 1.5 kg. It is mainly composed of neurons – the fundamental... View Article

After observing Fig. answer the following. a) Read the following statements and label them in the figure: i) The part which produces female gametes. ii) The part where the development of the baby takes place. iii) The part through which the developing embryo passes to reach the uterus. b) Explain the future development of the embryo that would take place after it gets embedded in the uterus.

Solution: Ovary Uterus Oviduct The developing embryo gets embedded in the wall of the uterus for further development. The embryo continues to... View Article

Figure shows the two crop fields [Plots A and B] have been treated by manures and chemical fertilizers respectively, keeping other environmental factors same. Observe the graph and answer the following questions. (i) Why does plot B show sudden increase and then gradual decrease in yield? (ii) Why is the highest peak in plot A graph slightly delayed? (iii) What is the reason for the different pattern of the two graphs?

i) With addition of chemical fertilizer there is sudden increase in yield due to release of nutrients N,P,K etc in high quantity. The gradual... View Article