31) Why do we feel drowsy after a heavy meal?
(A) The biological clock is upset
(B) The body muscles are fatigued
(C) The hypothalamus produces melatonin to induce sleep
(D) Brain receives less oxygen as blood rushes to supply oxygen and nutrition to the contracting stomach and intestines
32) Ready source of energy available for athletes is
(A) Carbohydrates
(B) Fats
(C) Proteins
(D) Vitamins
33) Chromosomes are
(A) Present only in the nucleus of a cell
(B) The biggest in number in human cells
(C) Made up of DNA as a main component
(D) Visible in all cells at every time
34) The part of the cell which is essential for protein synthesis is
(A) Chloroplast
(B) Ribosomes
(C) Golgi bodies
(D) Chromosomes
35) Short sightedness is due to:
(A) Shifting of the iris
(B) Weaker muscles
(C) Elongation of eyeballs
(D) Weakening of the retina
36) There are approximately ____ muscles in human body
(A) 200
(B) 350
(C) 500
(D) 700
37) The organ which destroys worn out RBCs in the body of a vertebrate is
(A) Pancreas
(B) Bone marrow
(C) Liver
(D) Spleen
38) The saliva helps in the digestion of
(A) Proteins
(B) Fats
(C) Fibres
(D) Starch
39) Biological death of a patient means death of tissues of the
(A) Kidney
(B) Heart
(C) Lungs
(D) Brain
40) Which of the following hormones contains iodine?
(A) Adrenaline
(B) Insulin
(C) Testosterone
(D) Thyroxine