1.
Which of the following is an example of disaccharide?
Correct Answer
D. Maltose
Explanation
Maltose is an example of a disaccharide because it is made up of two glucose molecules bonded together. Disaccharides are carbohydrates composed of two monosaccharide units joined by a glycosidic bond. Glucose, fructose, and galactose are all monosaccharides, meaning they consist of a single sugar unit. Maltose, on the other hand, is a disaccharide formed by the condensation of two glucose molecules.
2.
Which of the following carbohydrates is a triose?
Correct Answer
D. D) Glyceraldehyde
Explanation
Glyceraldehyde is a triose because it is a carbohydrate that contains three carbon atoms. Triose sugars are the simplest type of sugar and have a general formula of C3H6O3. Glucose, ribose, and ribulose are all sugars, but they have more than three carbon atoms, making them not trioses.
3.
Lactose is a disaccharide of which of the following sugar units?
Correct Answer
B. Glucose and galactose
Explanation
Lactose is a disaccharide composed of two sugar units: glucose and galactose. These two monosaccharides are bonded together through a glycosidic linkage. Lactose is commonly found in milk and dairy products and needs to be broken down by the enzyme lactase in order to be digested by individuals who are lactose intolerant.
4.
Which of the following enzyme catalyzes the first step of glycolysis?
Correct Answer
A. Hexokinase
Explanation
Hexokinase is the correct answer because it catalyzes the first step of glycolysis, which is the conversion of glucose to glucose-6-phosphate. This enzyme adds a phosphate group to glucose, trapping it within the cell and initiating the breakdown process. Pyruvate kinase catalyzes the last step of glycolysis, while glucokinase and phosphofructokinase-1 are enzymes involved in other steps of the pathway.
5.
What is the general term used for the anaerobic degradation of glucose to obtain energy?
Correct Answer
C. Fermentation
Explanation
Fermentation is the correct answer because it refers to the anaerobic degradation of glucose to obtain energy. During fermentation, glucose is broken down into simpler molecules, such as alcohol or lactic acid, in the absence of oxygen. This process is commonly used in the production of alcoholic beverages, bread making, and certain types of cheese.
6.
Whenever the cell’s ATP supply is depleted, which of the following enzyme’s activity is increased?
Correct Answer
D. pHospHofructokinase-1
Explanation
When the cell's ATP supply is depleted, the activity of Phosphofructokinase-1 is increased. This is because Phosphofructokinase-1 is an important enzyme in the glycolysis pathway, which is the main pathway for ATP production in cells. When ATP levels are low, the cell needs to produce more ATP to meet its energy demands. Phosphofructokinase-1 is responsible for catalyzing a key step in glycolysis, the conversion of fructose-6-phosphate to fructose-1,6-bisphosphate. By increasing the activity of Phosphofructokinase-1, the cell can enhance the rate of glycolysis and generate more ATP.
7.
Dihydroxyacetone phosphate is rapidly and reversibly converted to
Correct Answer
A. Glyceraldehyde 3-pHospHate
Explanation
Dihydroxyacetone phosphate is rapidly and reversibly converted to Glyceraldehyde 3-phosphate. This conversion occurs during the glycolysis pathway, specifically during the isomerization step catalyzed by the enzyme triose phosphate isomerase. Dihydroxyacetone phosphate is isomerized into Glyceraldehyde 3-phosphate, which is an important intermediate in the glycolysis pathway and can be further metabolized to produce ATP.
8.
Name the pathway for glucose synthesis by non-carbohydrate precursors?
Correct Answer
C. Gluconeogenesis
Explanation
Gluconeogenesis is the pathway for glucose synthesis by non-carbohydrate precursors. It is a metabolic pathway that occurs in the liver and kidneys, where glucose is produced from non-carbohydrate sources such as amino acids, lactate, and glycerol. This process is essential for maintaining blood glucose levels during periods of fasting or low carbohydrate intake. Glycogenesis, on the other hand, is the process of glycogen synthesis, while glycolysis is the breakdown of glucose for energy production. Glycogenolysis is the breakdown of glycogen into glucose.
9.
What is the site for gluconeogenesis?
Correct Answer
A. Liver
Explanation
The correct answer is liver. Gluconeogenesis is the process of synthesizing glucose from non-carbohydrate sources, such as amino acids and glycerol. The liver is the primary site for gluconeogenesis in the body. It has the necessary enzymes and metabolic pathways to convert these non-carbohydrate molecules into glucose. The liver then releases the glucose into the bloodstream to maintain blood sugar levels and provide energy to other tissues and organs.
10.
Name the enzyme which is responsible for the conversion of pyruvate to phosphoenolpyruvate (PEP)?
Correct Answer
B. Pyruvate carboxykinase
Explanation
Pyruvate carboxykinase is the correct answer because it is the enzyme responsible for the conversion of pyruvate to phosphoenolpyruvate (PEP). Pyruvate carboxykinase catalyzes the decarboxylation of pyruvate and the transfer of a phosphate group to produce PEP. This enzyme plays a crucial role in gluconeogenesis, the process by which glucose is synthesized from non-carbohydrate precursors.
11.
Name the most active organs in the animal body which have the ability to synthesize triacylglycerol?
Correct Answer
C. Liver and intestines
Explanation
The liver and intestines are the most active organs in the animal body that have the ability to synthesize triacylglycerol. Triacylglycerol, also known as triglyceride, is a type of fat molecule that is important for energy storage in the body. The liver is responsible for synthesizing and storing triacylglycerol, while the intestines play a role in absorbing dietary fats and converting them into triacylglycerol for storage. Adipose tissues, although involved in fat storage, do not have the ability to synthesize triacylglycerol themselves.
12.
What is lipolysis?
Correct Answer
A. Hydrolysis of triacylglycerol
Explanation
Lipolysis refers to the process of hydrolyzing or breaking down triacylglycerol molecules. Triacylglycerol is a type of lipid that consists of three fatty acid chains attached to a glycerol molecule. During lipolysis, enzymes called lipases break the ester bonds between the fatty acids and the glycerol, resulting in the release of free fatty acids and glycerol. This process typically occurs in adipose tissue and is important for the mobilization and utilization of stored fat as an energy source.
13.
Mark the INCORRECT statement about the bile salt.
Correct Answer
C. It is hydropHobic in nature
Explanation
Bile salts are hydrophilic in nature, not hydrophobic. They have a hydrophilic (water-loving) region and a hydrophobic (water-repelling) region, which allows them to emulsify fats in the digestive system. This property enables them to break down larger fat droplets into smaller ones, increasing the surface area for enzymes to act upon and aiding in the digestion and absorption of fats.
14.
What is the outcome of the accumulation of acetyl-CoA in the mitochondria of the liver?
Correct Answer
D. It forms ketone bodies
Explanation
When there is an accumulation of acetyl-CoA in the mitochondria of the liver, it can lead to the formation of ketone bodies. Ketone bodies are produced as an alternative energy source when glucose is not readily available, such as during periods of fasting or low carbohydrate intake. The liver converts acetyl-CoA into ketone bodies, which can then be used as fuel by other tissues in the body, including the brain. This process is known as ketogenesis and is an important metabolic pathway in maintaining energy balance during times of limited glucose availability.
15.
Name the energy source of the brain during starvation?
Correct Answer
B. Ketone bodies
Explanation
During starvation, when the body does not have enough glucose for energy, it starts breaking down fats stored in adipose tissue. This process generates ketone bodies as an alternative source of energy for the brain. Ketone bodies, such as acetoacetate and beta-hydroxybutyrate, are produced in the liver and can cross the blood-brain barrier to provide fuel to the brain cells. Therefore, ketone bodies are the energy source for the brain during starvation.
16.
What is the biosynthetic source of all steroid hormones?
Correct Answer
A. Cholesterol
Explanation
Cholesterol is the biosynthetic source of all steroid hormones. Steroid hormones are derived from cholesterol through a series of enzymatic reactions. Cholesterol serves as the precursor molecule for the synthesis of hormones such as cortisol, aldosterone, estrogen, and testosterone. These hormones play crucial roles in various physiological processes, including metabolism, reproduction, and stress response. Therefore, cholesterol is the correct answer as it is the starting point for the biosynthesis of all steroid hormones.
17.
Which of the following membrane is responsible for the protection of the heart?
Correct Answer
A. Epicardium
Explanation
The epicardium is the outermost layer of the heart and is responsible for providing protection to the heart. It is a thin membrane that covers the surface of the heart and helps prevent damage from external forces. The epicardium also contains blood vessels and nerves that supply the heart with oxygen and nutrients. Additionally, it produces a lubricating fluid that reduces friction as the heart beats.
18.
ECG records electrical changes in which of the following layers of the heart, mark the correct option.
Correct Answer
D. Myocardium
Explanation
The myocardium is the correct answer because it is the layer of the heart that is responsible for the contraction and pumping action. It is composed of cardiac muscle cells and is the thickest layer of the heart. ECG (electrocardiogram) records the electrical activity of the heart, including the depolarization and repolarization of the myocardium during each heartbeat. By analyzing the electrical changes in the myocardium, doctors can diagnose various heart conditions and abnormalities.
19.
In the adult truncus arteriosus forms the following structures
Correct Answer
Aorta Pulmonary trunk
Explanation
The adult truncus arteriosus forms two major structures: the aorta and the pulmonary trunk. The aorta is responsible for carrying oxygenated blood from the heart to the rest of the body, while the pulmonary trunk carries deoxygenated blood from the heart to the lungs for oxygenation. These two structures are essential for the proper functioning of the circulatory system, ensuring that oxygen is delivered to the body's tissues and carbon dioxide is removed.
20.
Bulbus cordis forms
Correct Answer
C. Smooth portion of both ventricles
Explanation
The bulbus cordis forms the smooth portion of both ventricles. The bulbus cordis is a part of the embryonic heart tube that gives rise to the outflow tracts of the ventricles. It undergoes extensive remodeling during development to form the smooth-walled portions of both the right and left ventricles. These smooth portions of the ventricles are important for the efficient ejection of blood from the heart.
21.
Aortic arch 3 forms the following structures
Correct Answer
Common carotid artery and internal carotid artery
Explanation
Aortic arch 3 is responsible for the formation of the common carotid artery and internal carotid artery. These arteries are important for the supply of blood to the head and neck region. The common carotid artery branches into the external carotid artery, which supplies blood to the face and scalp, and the internal carotid artery, which supplies blood to the brain. The internal carotid artery is a major supplier of blood to the brain, making it a crucial structure for maintaining proper brain function.
22.
Aortic arch 6 forms
Correct Answer
pulmonary artery and ductus arteriosus
Explanation
During embryonic development, the aortic arches are a series of blood vessels that form in the pharyngeal arches. Aortic arch 6 specifically gives rise to the pulmonary artery and the ductus arteriosus. The pulmonary artery carries deoxygenated blood from the heart to the lungs, while the ductus arteriosus is a temporary blood vessel that connects the pulmonary artery to the aorta, allowing blood to bypass the non-functioning lungs in the fetus.
23.
What muscles attach on the sternum?
Correct Answer
Pectoralis major, Transversus thoracis,
Explanation
The pectoralis major and transversus thoracis muscles attach to the sternum. The pectoralis major is a large muscle located in the chest that helps to move and stabilize the shoulder joint. It originates from the clavicle, sternum, and ribs and inserts into the humerus. The transversus thoracis is a thin muscle that lies deep to the pectoralis major and helps to depress the ribs during exhalation. It originates from the lower sternum and inserts into the ribs.
24.
Abbreviate SCALP
Correct Answer
Skin connective tissue Aponeurosis loose connective tissue Periosteum
Explanation
The correct answer is SCALP, which stands for Skin, Connective tissue, Aponeurosis, Loose connective tissue, and Periosteum. The scalp is composed of these layers, starting from the outermost layer (skin) and progressing inward. The skin provides protection and acts as a barrier, while the connective tissue provides support and structure. The aponeurosis is a broad, flat tendon that connects muscles to bones, and in the scalp, it helps to anchor the scalp to the skull. The loose connective tissue provides cushioning and flexibility, and the periosteum is a membrane that covers the bones of the skull.
25.
How many pairs of spinal nerves are
there
Correct Answer
31
Explanation
There are 31 pairs of spinal nerves.