406: After sowing seeds, the fertilisers used are:
(a) Phosphates
(b) Nitrates
(c) Green manures
(d) All of these
407: Match List I (Drugs / Chemicals) with List II (Their uses) and select the correct answer using the codes given below the Lists :
List I---------------List II
I. Atropine---------(A) Local anaesthesia
II. Ether------------(B) Heart trouble
III. Nitroglycerine---(C) Dilation of pupil
IV. Pyrethrin--------(D) Mosquito control
Codes:
(a) I-A, II-C, III-B, IV-D
(b) I-A, II-C, III-D, IV-B
(c) I-C, II-A, III-D, IV-B
(d) I-C, II-A, III-B, IV-D
408: Which one of the following is caused by the expression of a recessive gene present on sex chromosome ?
(a) Rheumatism
(b) Nervous shock
(c) Muscular dystrophy
(d) Cerebral hemorrhage
409: Dehydration in the human body results due to loss of:
(a) Salts
(b) Water
(c) Vitamins
(d) Hormones
410: With reference to 'stem cells', frequently in the news, which of the following statements is/are correct?
1. Stem cells can be derived from mammals only.
2. Stem cells can be used for screening new drugs.
3. Stem cells can be used for medical therapies.
Select the correct answer using the codes given below :
(a) 1 and 2 only
(b) 2 and 3 only
(c) 3 only
(d) 1, 2 and 3
Explanation:
Stem cells are biological cells found in all multicellular organisms, that can divide (through mitosis) and differentiate into diverse specialized cell types and can self-renew to produce more stem cells. In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. Hence option 1 is not correct.
Medical researchers believe that stem cell therapy has the potential to dramatically change the treatment of human disease. A number of adult stem cell therpies already exist, particularly bone marrow transplants that are used to treat leukemia. In the future, medical reserachers anticipate being able to use technologies derived from stem cell research to treat a wider variety of diseases including cancer, Parkinson's disease, spinal cord injuries, Amyotrophic lateral scleosis, multiple sclerosis, and muscle damage, amongst a number of other impairments and conditions. Hence option 2 and 3 are both correct.