User Forum

Given below is a list of few harmful effects on humans.
(i) Cancer
(ii) Cataract in eyes
(iii) Lowering of body's resistance to diseases
(iv) Increased mortality of developing embryo
Which of these are caused due to ozone depletion?

A(i) and (iii) only
B(ii) and (iv) only
C(iii) and (iv) only
D(i), (ii), (iii) and (iv)

A boy of mass 50 kg runs up a flight of 120 stairs, each measuring a height of 25 cm, in one minute and 40 seconds. If g = 10 m s^-2, the power of the boy is

A 150 W
B 750 W
C 500 W
D 250 W

Refer to the given figures showing seeds/fruits ofthree different plants.

Select the option which contains plants that can replace X, Y and Z, respectively based on the mode of dispersal of their seeds.

AX - Lotus; Y - Beans; Z - Calotropis
BX - Castor; Y - Coconut; Z - Acer
CX - Hiptage; Y - Balsam; Z - Cocklebur
DX - Mango; Y - Cotton; Z - Maize

The given figure shows the movement of food through the oesophagus. This movement is aided by the muscles of the oesophagus in a wave-like action called


A Diapedesis
B Peristalsis
C Rumination
D Muscularisation.

The given list shows the five steps needed to do a starch test but in a random order.
(i) Pluck a leaf from the plant.
(ii) Leave a potted plant out in the Sun for a few hours.
(iii) Boil the leaf in alcohol.
(iv) Put the leaf in boiling water for 2 minutes.
(v) Wash the leaf and then add a few drops of iodine solution over it.
Select the option with correct order of these steps.

A (i), (ii), (iii), (iv), (v)
B (i), (ii), (iv), (iii), (v)
C (ii), (i), (v), (iv), (iii)
D (ii), (i), (iv), (iii), (v)

A student performed the first set of experiments with four test tubes containing solutions and metal pieces as indicated in the figure. In the second set of experiments, the metal pieces are interchanged between test tubes P and Q and also between test tubes R and S.

In which test tube(s), no reaction will occur in both sets of experiments?

A P and Q
B R
C S
D R and S.

I am a part of the leaf that carries water to it. I give rise to many thinner branches. I am a ___________.

A Leaf blade
B Lamina
C Mid vein
D None of these

Sheep are the major source of wool. During the production of wool from a sheep, it passes through several steps, such as scouring (P), drying (Q), dyeing (R), spinning (S), shearing (T) and carding (U).Which of the following options shows the correct sequence of these steps?

AT → P → Q → U → R → S
BP → T → Q → R → U → S
CU → P → R → Q → T → S
DR → P → Q → T → S → U

Ravi in his dream saw a strange animal which had six legs, orange hair on skin and one eye on the forehead. It was feeding its young one milk. If really existed, it would have belonged to the same group as _____.

A Guppy fish
B Butterfly
C Crocodile
D Cow

Which of the following joints is present between thigh bone and shin bone?

AHinge joint
BPivot joint
CFixed joint
DBall and socket joint