Biology

321. Colour of urine is of light yellow colour due to the presence of –

1. Urobilin
2. Creatine
3. Alleles
4. Ammonia

Option “1” is correct
Urine color generally ranges from a pale-yellow color to deep amber. This coloring is primarily caused by the pigment urochrome, also known as urobilin.
322. When a person becomes older, his blood pressure generally —

1. Decreases
2. Increases
3. Remains the same
4. Varies widely

Option “2” is correct
The causes of high blood pressure are not known, but several factors and conditions may play a role in its development, including : Smoking, being overweight or obese, lack of physical activity, too much salt in the diet, too much alcohol consumption, Stress, older age, genetics, family history of high blood pressure, chronic kidney disease, adrenal and thyroid disorders.
323. Average blood pressure of a human is –

1. 60/100
2. 20/80
3. 60/140
4. 120/80

Option “4” is correct
Ideally, a normal human must have a blood pressure (120/80). This means that systolic pressure around 120 mm Hg and diastolic pressure should be around 80 mm Hg.
324. Assertion (A): People with AB blood groups are universal recipients.
Reason (R): Red blood cell of blood group AB has no antigen and so agglutination does not occur with any other blood group.
Code:1. Both (A) and (R) are individually true, and (R) is the correct explanation of (A).
2. Both (A) and (R) are individually true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is true, but (R) is true.
Option “3” is correct
Blood group AB individuals have both A and B antigens on the surface of their RBCs and their blood plasma does not contain any antibodies. Therefore an individual with type AB blood can receive blood from any group , but cannot donate blood to any group other than AB. They are known as universal recipients.
325. The part of brain which controls emotional reactions in our body is –

1. Hypothalamus
2. Cerebrum
3. Meninges
4. Thalamus

Option “1” is correct
The brain’s limbic system controls emotional expression through the hypothalamus, which has control over the body’s emotional responses systems. The hypothalamus is responsible for regulating hunger, thirst, response to pain, levels of pleasure, sexual satisfaction, anger and aggressive behavior, etc.
326. Carrot is orange in colour because –

1. it grows in the soil
2. it is not exposed to sunlight
3. it contains carotene
4. the entire plant is orange in colour

Option “3” is correct
The carrot gets its characteristic and bright orange colour from the pigment called carotene.
327. Water in plants is transported by –

1. Cambium
2. Phloem
3. Epidermis
4. Xylem

Option “4” is correct
Water in plants is transported by Xylem.
328. The disease caused by swelling of the membrane over spinal cord and brain is-

1. Leukaemia
2. Paralysis
3. Sclerosis
4. Meningitis

Option “4” is correct
Meningitis is a disease caused by the inflammation of the protective membranes covering the brain and spinal cord known as meninges.
329. One out of every 200 babies born in India, dies of diarrhea caused by:

1. Bacteria
2. Rotavirus
3. Amoeba
4. Fungus

Option “2” is correct
The rotavirus is a group of RNA viruses, some of which cause acute enteritis in humans. Rotavirus is the most common cause of severe diarrhea among infants and young children. It is a genus of double-stranded RNA virus in the family Reoviridae.
330. The disease hysteria is classed in-

1. Women
2. Men
3. Boy
4. None of these

Option “1” is correct
Hysteria disease is mainly classed in women. It is a genital disease in which the symptoms of anxiety, discomfort and faintness are found.