Option “3” is correct. Skin cancer is caused due to presence of excess arsenic in water.
153. Animals living in the tree trunks are known as –
1. Arboreal
2. Volant
3. Amphibious
4. Aquatics
Option “1” is correct. Arboreal is defined as something having the evolutionary characteristics of animals which allow them to live or maneuver through trees. An example of an arboreal part of the chimpanzee’s anatomy is its long arms.
154. Which of the following is correct about cold-blooded animals?
1. Their blood remains cold all the time
2. Their body temperature changes in accordance with atmosphere
3. Their body temperature remains constant all the time
4. They kill all the animals they came across.
Option “2” is correct. Cold-blooded creatures take on the temperature of their surroundings. They are hot when their environment is hot and cold when their environment is cold. In hot environments, cold-blooded animals can have blood that is much warmer than warm-blooded animals so thier body temperature changes in accordance to temperature of atmosphere.
155. Which of the following animals has the longest life span?
1. Elephant
2. Crocodile
3. Dog
4. Tortoise
Option “4” is correct. Tortoise has longest span of life.
156. The branch of biology dealing with the study of cells is known as –
Option “1” is correct. Cytology is a branch deals with study of cells.
157. Which is the anti-coagulant substance in blood?
1. Fibrinogen
2. Heparin
3. Thrombin
4. Globin
Option “2” is correct. Heparin is also known as unfractionated heparin, is medication which is used as an anticoagulant.
158. How many chromosomes are there in humans?
1. 36
2. 46
3. 56
4. 26
Option “2” is correct. In humans, each cell normally contains 23 pairs of chromosomes, a total of 46.
159. The strongest muscle in human body is found in-
1. Jaws
2. Thighs
3. Neck
4. Hands
Option “1” is correct. The strongest muscle based on its weight is the masseter. With all muscles of the jaw working together, it can close the teeth with a force as great as 55 pounds (25 kilograms) on the incisors or 200 pounds (90.7 kilograms) on the molars.
160. Which of the following is not a symptom of a heart attack?
1. Chest pain
2. Nausea and sweating
3. Numbness and aching of arms
4. Pain in legs
Option “4” is correct. A heart attack-medically was known as a myocardial infarction. The symptoms of heart attack include; pain or discomfort in one or both arms, back, neck, jaws or stomach. Shortness of breath with or without chest discomfort other signs such as breaking out in a cold sweat, nausea of lightheadedness. As with men and women’s most common heart attack symptom is chest pain or discomfort.
