Which of the following processes requires energy? 

(a) Movement of calcium into a cell. 

(b) Secretion of mucus by a cell 

(c) Entry of oxygen into a cell. 

(d) Water absorption by a cell.

Which process of cell ingestion is shown in diagram below?

(a) Exocytosis 

(b) Pinocytosis 

(c) Phagocytosis 

(d) Macrophage engulfing an infectious agent

A biologist was given two animal cell populations, X and Y. When he subjected them to culturing under similar conditions of availability of nutrients, growth factors and substratum he found the growth of sample X stopped after the available substratum was covered while the growth of sample Y continued so that multilayered mass was formed. The cells in sample X and Y respectively, are most likely to be: 

(a) epithelial cells and leucocytes 

(b) germinal cells and muscle cells 

(c) normal cells and cancer cells 

(d) diploid cells and polyploid cells

Deep sea sponges have silicate spicules because: 

(a) precipitation of calcium carbonate is hindered by the depth. 

(b) at greater depth sequestration of silica is easier. 

(c) only silicious spicules make circulation of water through body efficient. 

(d) availability of calcium is relatively less at depth.

A littoral gastropod will have thickest shell when it is located at the 

(a) high tide marks on a rock beach. 

(b) greatest depth in a sand beach. 

(c) low tide marks on a mud beach. 

(d) bottom of a rock pool

Which of the following statements about human disorders caused by different organelles is true? 

(a) Peroxisomal disorders are due to mutations in nuclear genes. 

(b) Mitochondrial disorders are always due to mutations in maternally inherited mitochondrial genes. 

(c) Person can suffer from lysosomal storage diseases even if lysosomal hydrolases are synthesized in sufficient quantities. 

(d) Inefficient recycling of long chain fatty acids is likely to be a result of mitochondrial disorder.

Observe the given diagram and select the possible reason for the movement of water through the Semipermeable membrane (SM) separating sides A and B:

(a) Addition of solute reduces the water potential in side A hence water moves from A to B: 

(b) Withdrawal of piston in side, B increases water potential hence water move from A to B. 

(c) Due to atmospheric pressure in side A, water potential becomes 0 and hence water moves from A to B. 

(d) Withdrawal of piston in side B decreases the water potential and hence water moves from A to B.

 If blood of healthy human is tested after high protein meal, which of the following will not be observed? 

(a) Considerable increase in plasma glucose level. 

(b) Raised insulin level. 

(c) High plasma glucagon level. 

(d) Increased amino acids level.

The extend of tilt in the earth’s rotation has no influence on : 

(a) patterns of global climate 

(b) different seasons 

(c) periods of glacial expansion/retreat. 

(d) atmospheric concentrations of gases.

If a quantitative character is influenced by an additive effect of four genes, how many phenotypic categories are expected in the progeny of a tetrahybrid cross? 

(a) 5 

(b) 7 

(c) 9 

(d) 11