User Forum

Kepler's third law states that square of period of revolution (T) of a planet around the sun is proportional to third power of average distance r between the sun and the planet i.e. T² = Kr³ (here K is constant). If the masses of sun and planet are M and m respectively then as per Newton's law of gravitation, force of attraction between them is F = GMm/r², here G is gravitational constant.
The relation between G and K is described as

A K = G
B K = 1/G
C GK = 4π²
D GMK = 4π²

Direction : Refer to the given dichotomous key regarding cell organelles and answer the questions 49 and 50.


AP can be ER and Q can be Golgi apparatus.
BR can be chloroplasts and S can be ribosomes.
CP can be nucleus and T can be ribosomes.
DR can be mitochondria and S can be lysosomes.

If four identical balls are dropped at the same time and from the same height, which ball will land first?


ABall 1
BBall 2
CBall 3
DBall 4

Ridhan classified animals in four groups on the basis of their feeding habits. In doing so, he wrongly placed one animal in one of the groups. Identify this group and select the correct option.

A Giraffe, rabbit, wildebeest and deer
B Crocodile, crow, snake and eagle
C Leech, mosquito, lice and bed bug
D Tiger, snow leopard, wolf and lion

The given figure shows a typical animal cell with its parts being labelled as 'a - j'. Identify the labelled parts and select the incorrect option regarding it.


A The organelles e, h, g and i are membrane-bound organelles which function in close coordination with one another.
B 'f' organelle is responsible for the synthesis of fats inside the cells and it stores Ca²⁺ for release during muscle contraction.
C a and b have selective permeability i.e., they allow only selected substances to pass inwardly.
D 'j' is the site for protein synthesis. It allows hereditary message from 'd' to get translated into proteins.

The given set-up shows the separation process of a mixture of water and materials X and Y. X and Y respectively could be_______.


AMud and salt
BSalt and sugar
CSugar and salt
DMud and clay

Refer to the given flow chart and select the incorrect statement regarding W, X, Y and Z.


A W could be abundant in RBCs whereas X could be absent in xylem parenchyma.
B Y provides energy during starvation whereas Z provides surface for synthesis of steroid hormones.
C W helps in synthesis of proteins whereas Y secretes enzymes which are used for breaking limiting membrane of eggs.
D X could provide intermediates for the synthesis of certain steroids and cytochromes whereas Z stores calcium for release during muscle contraction.

The hairy skin of the sheep has two types of fibres that form its fleece: (i) the coarse beard hair and (ii) the fine soft under hair close to the skin. Which of the hair provide the fibres for making wool?

A(i)
B(ii)
C(i) and (ii)
DNone of these

Select the option which would most closely resembles the mirror image of the given Fig. (X), if the mirror is placed along MR.


A
B
C
D

Which of the following groups of organisms live in marine habitats?

A Whales, Crocodile, Sea turtle
B Whales, Jelly fish, Sea weed
C Fish, Frog, Tortoise
D Crab, Oyster, Duckweed