11. Which among the following nitrogenous wastes requires the least water for its excretion?
[A] Ammonia
[B] Urea
[C] Nitrites
[D] Uric Acid
Show Answer
Correct Answer: D [ Uric Acid]
Notes:
Uric acid is not soluble in water and is excreted as a dry crystal by the animal’s digestive system. Ammonia is the most toxic nitrogenous waste and must be excreted in large volumes of water.
12. In context with diabetes, many often we hear about Type1 and Type2 diabetes. What exactly are these?
[A] Body does not produce Insulin in Type1, does not respond properly in Type 2
[B] Body does not respond to Insulin properly in Type 1 , does not produce in Type 2
[C] Body produces too little Insulin in Type 1 , produces too much insulin in Type 2
[D] Body produces too much insulin in Type 1, produces too little insulin in Type 1
Show Answer
Correct Answer: A [Body does not produce Insulin in Type1, does not respond properly in Type 2]
Notes:
Diabetes mellitus occurs when the body does not produce insulin (type I) or when the body does not respond properly to insulin (type II). This results in elevated blood glucose. In either type, overtreatment, or failure to eat properly while on treatment, can lead to hypoglycemia. Most diabetics recognize their symptoms when “low” and know to go eat something before it progresses to a dangerous point. Symptoms of high blood sugar are much different – thirst, increased urination, sleepiness.
13. Which among the following carries impure blood to human heart?
[A] Pulmonary vein
[B] Vena Cava
[C] Aorta
[D] Pulmonary arteries
Show Answer
Correct Answer: D [Pulmonary arteries]
Notes:
The pulmonary artery carries impure blood to the right and left lungs. The left half of the heart collects and pumps pure (oxygenated) blood from the lungs to all parts of the body.
14. Which of the following is the function of the liver? (UPSC Prelims 1979).
[A] Promote digestion of food
[B] Promote respiration
[C] Store glucose as glucogen
[D] None of these
Show Answer
Correct Answer: C [Store glucose as glucogen]
Notes:
The liver’s main job is to filter the blood coming from the digestive tract, before passing it to the rest of the body. The primary functions of the liver are:
• Bile production and excretion
• Excretion of bilirubin, cholesterol, hormones, and drugs
• Metabolism of fats, proteins, and carbohydrates
• Enzyme activation
• Storage of glycogen, vitamins, and minerals
• Synthesis of plasma proteins, such as albumin, and clotting factors
15. Which of the following facts is true regarding Colour blindness?
[A] More common among women
[B] Very rare in women
[C] Very rare in men
[D] Found to the same extent in both the sexes
Show Answer
Correct Answer: B [Very rare in women]
Notes:
Color blindness occurs when light-sensitive cells in the retina fail to respond appropriately to variations in wavelengths of light that enable people to see an array of colors. Photoreceptors in the retina are called rods and cones. It is very rare in women.
16. Which of the following correctly define Amniocentesis? (UPSC Prelims 1988)
[A] Determination of foetal sex
[B] Separation of amino acids
[C] Determination of the sequence of amino acids in a protein
[D] Inducing abortion
Show Answer
Correct Answer: A [Determination of foetal sex]
Notes:
Amniocentesis is a medical procedure used primarily in prenatal diagnosis of chromosomal abnormalities and foetal infections, as well as for sex determination.
17. Why man cannot digest cellulose whereas cows can do so? (UPSC Prelims 1992)
[A] Their gut contains certain bacteria capable of digesting cellulose
[B] They have a many-chambered stomach
[C] They have efficient grinding molars
[D] They produce enzyme cellulose which can digest cellulose
Show Answer
Correct Answer: A [Their gut contains certain bacteria capable of digesting cellulose]
Notes:
Unlike cows for example don’t have the necessary bacteria in their intestines that make the enzymes necessary to breakdown the 1-4 beta glucose bonds. So we cannot break down cellulose into its constituent glucose molecules as we do with starch.
18. Which of the following contain a protein named Alpha-keratin? (UPSC Prelims 1997)
[A] Blood
[B] skin
[C] wool
[D] eggs
Show Answer
Correct Answer: B [skin]
Notes:
Alpha-keratin, or α-keratin, is a type of keratin found in vertebrates. This protein is the primary component in hair, horns, mammalian claws, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure.
19. Which of the following branch of biology deals with the study and rearing of grasses?
[A] Agrostology
[B] Agronomy
[C] Dendrology
[D] Phenology
Show Answer
Correct Answer: A [Agrostology]
Notes:
Agrostology, the branch of botany concerned with the study of grasses, especially their taxonomy.
20. Which branch of biology is known for the study of plant fossils?
[A] Paleobotany
[B] Morphology
[C] Lichenology
[D] Agronomy
Show Answer
Correct Answer: A [Paleobotany]
Notes:
Paleobotany is the scientific study of ancient plants using plant fossils found in sedimentary rocks.
