STD 12 - 4. principal of inheritance and variation — NEET STD 11 Science — Question

Doctors use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when

Medulla oblongata controls

The chromosome maps are not accurate maps because

The common Indian bull frog is

The immune system which works against self is

Match the Column-I with Column-II:

Column I	Column II
(a) P-wave	(i) Depolarisation of ventricles
(b) QRS complex	(ii) Repolarisation of ventricles
(c) T-wave	(iii) Coronary ischemia
(d) Reduction in the size of T-wave	(iv) Depolarisation of atria
	(v) Repolarisation of atria

Which one of the following is a living fossil

Which one of the following phenomena supports Darwin’s concept of natural selection in organic evolution

Fill in the blanks and choose the correct option given below.
(i) The sequence of periods in geological time sequence: Silurian Devonian Carboniferous A Triassic B Cretaceous C Quaternary.
(ii) Around 200 mya, some of land reptiles e.g. D went back into water to evolve into fish like reptiles.
(iii) The biggest dinosaur was E which was about 20 feet in height and had huge fearsome dagger like teeth.
(iv) Due to F pouched mammals of Australia survived because of lack of competition from any other mammals.
(v) About 15 mya, primates called G (which was more ape-like) and H (which was more man- like) were existing.
(vi) Around 2 mya, primates called I lived in East African grasslands, ate fruit and hunted with stone weapon.
(vii) The first human-like being the hominid was called J, whose brain capacity was K cc.
(viii) The L with brain size of 1400cc lived in near East and Central Asia between 1,00,000 - 40,000 years back. They used hides to protect their body and buried their dead.
(ix) Homo sapiens arose in M and moved across continents and developed into distinct races.
(x) Agriculture came around N years back and human settlements started.

Which of the following statements are not correct for disorders of circulatory system ?
(i) If repeated checks of blood pressure of an individual is 140/90 (140 over 90) or higher, it shows hypertension.
(ii) High blood pressure leads to heart diseases and also affects vital organs like brain and kidney.
(iii) Coronary artery disease, often referred to as atherosclerosis, affects the vessels that supply blood to the heart muscle.
(iv) Atherosclerosis is caused by deposits of calcium, fat, cholesterol and fibrous tissues, which makes the lumen of arteries narrower.
(v) Angina or angina pectoris is acute chest pain which appears when no enough oxygen is ching the heart muscle.
(vi) Angina can occur in men and women of any age but it is more common among the middle-aged and elderly.
(vii) Heart failure is same as cardiac arrest or a heart attack.