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📘 Study MCQs
Q1. The simplest form into which fats are broken down during digestion is called DEFINITION
• Glucose
• Amino acid
• Fatty acid
• Glycerol
Answer: Fatty acid
Fats are complex molecules that are not easily absorbed.
Digestion breaks fats down into their building blocks: fatty acids and glycerol.
These smaller molecules can then be absorbed through the villi in the small intestine.
Q2. Along with fatty acids, fats are broken down into another simple substance called DEFINITION
• Glucose
• Amino acid
• Fatty acid
• Glycerol
Answer: Glycerol
Glycerol is the backbone molecule of a fat.
When fats are digested by enzymes like lipase, they are split into glycerol and fatty acids.
Both substances are small enough to be absorbed into the bloodstream.
Q3. The bubble-like structure inside an amoeba where food is trapped and digested is called the DEFINITION
• Nucleus
• Pseudopodia
• Food vacuole
• Contractile vacuole
Answer: Food vacuole
When an amoeba engulfs food with its pseudopodia, it forms a food vacuole.
This vacuole is like a temporary stomach inside the single cell.
Digestive enzymes are released into the food vacuole to break down the food.
Q4. The small, sac-like organ that stores bile juice before it is released into the small intestine is called the DEFINITION
• Liver
• Pancreas
• Gall bladder
• Stomach
Answer: Gall bladder
The liver produces bile continuously, but it is not always needed for digestion.
The gall bladder stores this bile and releases it into the small intestine when food, especially fatty food, arrives.
It is a small, pear-shaped organ located beneath the liver.
Q5. The process of taking food into the body is technically called DEFINITION
• Digestion
• Absorption
• Ingestion
• Egestion
Answer: Ingestion
Ingestion is the very first step of nutrition.
It refers to the act of putting food into the mouth.
For example, a human eating an apple or a cow grazing on grass are both performing ingestion.
Q6. The largest gland in the human body that performs many functions, including secreting bile, is the FACT
• Pancreas
• Salivary gland
• Stomach
• Liver
Answer: Liver
The liver is the largest internal organ and gland in the human body.
It secretes bile, which is crucial for fat digestion.
It also performs other vital functions like storing nutrients and cleaning the blood.
Q7. The first set of teeth that grows in humans during infancy and begins to fall off by age six is called DEFINITION
• Permanent teeth
• Milk teeth
• Incisors
• Molars
Answer: Milk teeth
Milk teeth are also known as temporary or deciduous teeth.
A child has 20 milk teeth.
These teeth are eventually replaced by 32 permanent teeth as the child grows.
Q8. The final set of teeth that replaces milk teeth and lasts for a lifetime is called DEFINITION
• Milk teeth
• Temporary teeth
• Permanent teeth
• Deciduous teeth
Answer: Permanent teeth
Permanent teeth are the second and last set of teeth in humans.
They start appearing around age 6 and continue until about age 12-13.
An adult normally has 32 permanent teeth, including incisors, canines, premolars, and molars.
Q9. The flat, broad teeth at the very back of the mouth used for grinding and chewing food are called DEFINITION
• Incisors
• Canines
• Premolars
• Molars
Answer: Molars
Molars are the largest and strongest teeth.
They are located at the back of the mouth and have a broad, flat surface.
Their main function is to grind food into small particles, making it easier to swallow and digest.
Q10. The tube that connects the mouth (buccal cavity) to the stomach is also known as the food pipe, or scientifically as the DEFINITION
• Trachea
• Oesophagus
• Intestine
• Colon
Answer: Oesophagus
The oesophagus is a muscular tube about 25 centimeters long.
It carries food from the throat to the stomach.
The walls of the oesophagus contract in a wave-like motion called peristalsis to push the food down.
Q11. The long, flat gland located behind the stomach that secretes pancreatic juice into the small intestine is called the DEFINITION
• Liver
• Gall bladder
• Pancreas
• Spleen
Answer: Pancreas
The pancreas is a vital organ that serves both digestive and hormonal functions.
It produces pancreatic juice, which contains enzymes that digest all major food types: carbohydrates, proteins, and fats.
This juice is released into the small intestine.
Q12. The teeth located between the canines and the molars, used for crushing and grinding food, are called DEFINITION
• Incisors
• Canines
• Premolars
• Molars
Answer: Premolars
Premolars are teeth that have a flat biting surface.
They are situated between the pointed canines and the large molars.
Their function is to tear and crush food, acting as a transition between the tearing canines and grinding molars.
Q13. The temporary, finger-like projections of an amoeba’s cell membrane that help it capture food are called DEFINITION
• Villi
• Cilia
• Flagella
• Pseudopodia
Answer: Pseudopodia
Pseudopodia, meaning “false feet,” are not permanent structures.
An amoeba extends its cell membrane to form these projections to flow around and engulf food particles.
They are also used for movement.
Q14. The first and largest chamber of a ruminant’s stomach where food first enters and is stored is the DEFINITION
• Reticulum
• Omasum
• Abomasum
• Rumen
Answer: Rumen
The rumen is a large, muscular sac.
It acts as a fermentation chamber where billions of bacteria begin breaking down cellulose.
The partially digested food in the rumen is called the cud.
Q15. An animal that has a four-chambered stomach and chews the cud, like a cow, is called a DEFINITION
• Carnivore
• Omnivore
• Ruminant
• Herbivore
Answer: Ruminant
A ruminant is a specific type of herbivore.
While all ruminants are herbivores, not all herbivores are ruminants.
The key feature of ruminants is their four-chambered stomach and the process of rumination (chewing the cud).
Q16. The entire process of chewing the cud, which involves bringing back partially digested food from the rumen to the mouth for re-chewing, is called DEFINITION
• Digestion
• Regurgitation
• Rumination
• Absorption
Answer: Rumination
Rumination is a unique digestive process in animals like cows and buffaloes.
It allows them to quickly swallow grass in the field and then later, in a safe place, bring it back up to chew it thoroughly.
This helps in the mechanical breakdown of tough plant fibers.
Q17. The glands present in the mouth that secrete saliva, which contains the enzyme salivary amylase, are called DEFINITION
• Gastric glands
• Pancreas
• Salivary glands
• Liver
Answer: Salivary glands
Salivary glands are located in and around the mouth.
There are three pairs of major salivary glands.
They secrete saliva, which moistens food and begins the chemical digestion of starch.
Q18. The finger-like projections present on the inner wall of the small intestine that greatly increase the surface area for absorption are called DEFINITION
• Pseudopodia
• Cilia
• Villi
• Rugae
Answer: Villi
Villi are tiny, finger-like structures that line the small intestine.
They make the inner surface of the intestine look like velvet.
Each villus contains blood vessels that absorb the digested food and carry it to all parts of the body.
Q19. The watery fluid secreted in the mouth that contains the enzyme salivary amylase is called DEFINITION
• Mucus
• Bile
• Gastric juice
• Saliva
Answer: Saliva
Saliva is the first digestive juice that comes into contact with food.
It is about 99% water, but contains important enzymes and mucus.
It helps in moistening the food and starting the digestion of starch.
Q20. The front teeth that are chisel-shaped and used for cutting and biting food are the DEFINITION
• Canines
• Premolars
• Molars
• Incisors
Answer: Incisors
Incisors are the eight teeth at the very front of the mouth (four on top, four on bottom).
They have a sharp, flat edge perfect for biting into food like an apple or cutting a piece of sandwich.
They are the first teeth to appear in babies.
Q21. A fatty acid is to fat as an amino acid is to a REASONING
• Carbohydrate
• Vitamin
• Protein
• Mineral
Answer: Protein
This is an analogy question about the building blocks of nutrients.
Fats are made up of smaller units called fatty acids and glycerol.
Similarly, proteins are made up of smaller units called amino acids.
Q22. In amoeba, if the food vacuole is the stomach, then the pseudopodia are like the REASONING
• Teeth
• Hands
• Intestine
• Blood
Answer: Hands
The pseudopodia in amoeba are used to capture and engulf food.
In humans, we use our hands to bring food to our mouth.
Therefore, pseudopodia perform a function similar to hands in the process of ingestion.
Q23. A cow is a ruminant, but a human is not. The main reason is that a cow has REASONING
• A longer small intestine.
• A four-chambered stomach.
• Incisors in the lower jaw only.
• A large liver.
Answer: A four-chambered stomach.
The defining characteristic of a ruminant is its specialized digestive system.
The four-chambered stomach (rumen, reticulum, omasum, abomasum) allows them to digest cellulose.
Humans have a single-chambered stomach and cannot digest cellulose efficiently.
Q24. Bile is produced in the liver but is stored in the FACT
• Pancreas
• Stomach
• Small intestine
• Gall bladder
Answer: Gall bladder
The liver constantly produces bile, but it is only needed when food enters the small intestine.
The gall bladder acts as a reservoir, storing and concentrating the bile until it is required.
When we eat a fatty meal, the gall bladder contracts and releases bile.
Q25. The function of the gall bladder is most similar to which of the following in a house? REASONING
• The kitchen where food is cooked.
• The water tank on the roof that stores water.
• The drainpipe that removes waste.
• The dining table where food is eaten.
Answer: The water tank on the roof that stores water.
The liver produces bile continuously, just as a water supply system provides water.
The gall bladder stores this bile until it is needed, similar to how a water tank stores water for later use.
When needed (digestion), it releases the bile.
Q26. The process of digestion in ruminants begins in the FACT
• Mouth
• Rumen
• Abomasum
• Small intestine
Answer: Rumen
While ruminants do chew grass initially, the major chemical digestion, especially of cellulose, begins in the rumen.
The rumen contains bacteria that produce the enzyme cellulase.
This is different from humans, where digestion begins in the mouth.
Q27. Which of the following teeth is most likely to be used for tearing a piece of meat? EXAMPLE BASED
• Incisor
• Canine
• Premolar
• Molar
Answer: Canine
Canines are the sharp, pointed teeth.
They are designed for piercing and tearing food.
In carnivores like lions and dogs, canines are very long and prominent for tearing flesh. In humans, they are smaller but still serve this purpose.
Q28. The enzyme present in saliva that begins the digestion of starch is called FACT
• Pepsin
• Trypsin
• Salivary amylase
• Lipase
Answer: Salivary amylase
Saliva contains an enzyme called salivary amylase, also known as ptyalin.
It acts on cooked starch, breaking it down into simpler sugars like maltose.
This is why a piece of bread starts tasting sweet if you chew it for a while.
Q29. Which of the following is NOT a part of the ruminant’s four-chambered stomach? FACT
• Rumen
• Reticulum
• Omasum
• Pancreas
Answer: Pancreas
The four chambers of a ruminant’s stomach are the rumen, reticulum, omasum, and abomasum.
The pancreas is a separate gland that lies near the stomach and secretes digestive juices into the small intestine. It is not a chamber of the stomach.
Q30. The process of taking food into the body (ingestion) in humans involves the mouth, but in amoeba, it involves the FACT
• Food vacuole
• Pseudopodia
• Nucleus
• Cell wall
Answer: Pseudopodia
Ingestion is the common first step, but the method differs based on the organism’s complexity.
Humans use complex organs like the mouth and teeth.
Amoeba, being unicellular, uses its temporary finger-like projections, the pseudopodia, to engulf food.
Q31. After a meal, the absorbed fatty acids and glycerol are transported from the small intestine to the rest of the body. This process is called DEFINITION
• Digestion
• Absorption
• Assimilation
• Egestion
Answer: Absorption
While digestion breaks down fats into fatty acids and glycerol, they still need to enter the body.
Absorption is the specific process where these simple molecules pass through the walls of the small intestine.
They then enter the lymphatic system or bloodstream to be transported.
Q32. The inner wall of the small intestine has numerous finger-like projections. If these projections were damaged and flattened, what would be the most likely consequence? REASONING
• Food would move too quickly through the intestine.
• Digestion of proteins would stop completely.
• The surface area for absorption would decrease, leading to less nutrient uptake.
• More bile would be produced.
Answer: The surface area for absorption would decrease, leading to less nutrient uptake.
Villi exist to increase the surface area of the small intestine.
A large surface area allows for maximum absorption of nutrients.
If the villi were damaged, the surface area would be drastically reduced, meaning fewer nutrients could be absorbed, even if digestion occurred normally.
Q33. The oesophagus connects the buccal cavity to the FACT
• Small intestine
• Large intestine
• Stomach
• Liver
Answer: Stomach
The oesophagus, or food pipe, is the muscular tube that forms the passage between the throat (pharynx) and the stomach.
Its sole function is to transport swallowed food and liquids to the stomach for further digestion.
Q34. Which of the following is NOT correctly matched? REASONING
• Incisor – Cutting
• Canine – Tearing
• Premolar – Grinding
• Molar – Biting
Answer: Molar – Biting
Molars are located at the back of the mouth and are used for grinding and chewing food into a fine paste.
Biting is the primary function of the incisors, which are the front teeth.
Therefore, the pair “Molar – Biting” is incorrect.
Q35. Saliva is secreted by the salivary glands. The enzyme in saliva, salivary amylase, helps in the digestion of FACT
• Proteins
• Fats
• Starch
• Cellulose
Answer: Starch
Salivary amylase is a specific enzyme that targets starch, a type of carbohydrate.
It begins the chemical breakdown of starch in the mouth itself.
Proteins are digested by enzymes like pepsin in the stomach, and fats by lipase with the help of bile.
Q36. The rumen of a ruminant contains billions of bacteria. These bacteria help the animal by digesting cellulose. In return, the bacteria get a home and food. This relationship is called DEFINITION
• Parasitism
• Predation
• Symbiosis
• Competition
Answer: Symbiosis
Symbiosis is a close, long-term interaction between two different organisms.
In the rumen, the bacteria (symbionts) get a protected environment and a constant supply of food.
The ruminant gets the ability to digest cellulose, which it cannot do on its own. This is a mutually beneficial (symbiotic) relationship.
Q37. A young child has 20 teeth. After the age of six, these teeth start falling out and are replaced by a new set. This new set is called FACT
• Milk teeth
• Temporary teeth
• Permanent teeth
• Deciduous teeth
Answer: Permanent teeth
The first set of teeth that fall out are the milk teeth.
The teeth that grow in their place are designed to last for the rest of a person’s life, hence they are called permanent teeth.
An adult has 32 permanent teeth.
Q38. The pancreas secretes its juices into the FACT
• Stomach
• Oesophagus
• Small intestine
• Large intestine
Answer: Small intestine
The pancreas is connected to the small intestine by a duct.
It releases pancreatic juice directly into the small intestine, not into the stomach.
This juice neutralizes the acidic chyme coming from the stomach and provides enzymes for digesting all types of food.
Q39. The acid present in our stomach kills many germs. What would likely happen if the stomach did not produce enough acid? REASONING
• Digestion of fats would stop.
• The person would get hungry more often.
• The person would have a higher chance of getting food poisoning or infections.
• The food would not be able to enter the small intestine.
Answer: The person would have a higher chance of getting food poisoning or infections.
Hydrochloric acid in the stomach creates an acidic environment that kills many harmful bacteria and microorganisms that enter with food.
If acid production is low, these germs may survive and pass into the intestines, potentially causing infections or food poisoning.
Q40. The teeth marked ‘P’ in a dental formula are called DEFINITION
• Incisors
• Canines
• Premolars
• Molars
Answer: Premolars
In dental formulas, different letters are used to denote different types of teeth.
‘I’ stands for Incisors, ‘C’ for Canines, ‘P’ for Premolars, and ‘M’ for Molars.
Therefore, ‘P’ in a dental formula represents the premolars.
Q41. Which chamber of a ruminant’s stomach is most similar in function to the human stomach? REASONING
• Rumen
• Reticulum
• Omasum
• Abomasum
Answer: Abomasum
The first three chambers of a ruminant’s stomach (rumen, reticulum, omasum) are mainly for storing, softening, and fermenting plant material with the help of bacteria.
The abomasum is the “true stomach” where digestive juices (gastric juices) are secreted to break down food chemically, just like in the human stomach.
Q42. Villi are to the small intestine as pseudopodia are to the REASONING
• Stomach
• Liver
• Amoeba
• Rumen
Answer: Amoeba
This is an analogy question. Villi are specialized structures present in the small intestine of humans.
Similarly, pseudopodia are specialized structures present in the cell of an amoeba.
Both structures help their respective organisms in the process of nutrition (villi for absorption, pseudopodia for ingestion).
Q43. The muscular contractions that push food through the oesophagus are known as DEFINITION
• Digestion
• Absorption
• Peristalsis
• Rumination
Answer: Peristalsis
Peristalsis is the involuntary constriction and relaxation of the muscles of the intestine or another canal, creating wave-like movements that push the contents forward.
It occurs not only in the oesophagus but throughout the digestive tract.
This movement ensures that food moves in one direction, even if you are lying down or standing on your head.
Q44. A person had their gall bladder removed surgically. Which of the following dietary changes would be most advisable? REASONING
• Eat more starchy foods like potatoes.
• Eat more protein-rich foods like meat.
• Avoid eating very fatty or oily foods.
• Drink more water with every meal.
Answer: Avoid eating very fatty or oily foods.
The gall bladder stores and concentrates bile, which is essential for digesting fats.
Without a gall bladder, bile is still produced but drips continuously into the intestine in small amounts.
The body cannot release a large amount of bile at once to handle a very fatty meal, so such meals might be difficult to digest, leading to discomfort.
Q45. The building blocks of proteins, which are absorbed by the villi, are called DEFINITION
• Fatty acids
• Glucose
• Amino acids
• Glycerol
Answer: Amino acids
Proteins are long chains of amino acids.
During digestion, these chains are broken down into individual amino acids.
These amino acids are small enough to be absorbed by the villi in the small intestine and then used by the body to build its own proteins.
Q46. The fluid in the mouth that contains an enzyme to digest starch is called DEFINITION
• Mucus
• Bile
• Saliva
• Gastric juice
Answer: Saliva
Saliva is the watery substance produced in the mouths of many animals.
In humans, it is secreted by the salivary glands.
It contains the enzyme salivary amylase, which begins the digestion of starch.
Q47. Which of the following is a function of the liver in digestion? FACT
• Storing food
• Secreting pancreatic juice
• Producing bile
• Chewing the cud
Answer: Producing bile
The liver has a direct role in digestion, which is the production of bile.
Bile is stored in the gall bladder and then released into the small intestine to aid in the digestion of fats.
The other options are functions of the stomach (storing food), pancreas (pancreatic juice), and mouth (chewing).
Q48. In an amoeba, the waste material after digestion is removed when the food vacuole fuses with the FACT
• Nucleus
• Pseudopodia
• Cell membrane
• Cytoplasm
Answer: Cell membrane
Egestion in amoeba is a simple process.
The food vacuole containing the undigested waste moves to the surface of the cell.
It then fuses with the cell membrane and opens up to release the waste material outside the body.
Q49. Milk teeth are also called temporary teeth. They begin to fall out around the age of six because REASONING
• They are not strong enough.
• The jaw grows bigger and needs larger, stronger permanent teeth.
• They get infected by bacteria.
• Children stop drinking milk.
Answer: The jaw grows bigger and needs larger, stronger permanent teeth.
As a child grows, their jawbone also grows in size.
The 20 milk teeth are the right size for a child’s small jaw.
To fit the larger jaw and to provide stronger teeth for an adult diet, the milk teeth are replaced by 32 larger permanent teeth.
Q50. A cow chews grass quickly and swallows it. The grass first goes into the rumen. From the rumen, it is sent back to the mouth in small lumps as cud. The path of the cud from the mouth back to the stomach for final digestion goes FACT
• Directly to the abomasum.
• Through the oesophagus to the reticulum, omasum, and then abomasum.
• Back to the rumen for more storage.
• Directly to the small intestine.
Answer: Through the oesophagus to the reticulum, omasum, and then abomasum.
When the cow chews the cud and swallows it again, it does not go straight to the abomasum.
The swallowed cud goes down the oesophagus and enters the reticulum first.
From there, it passes through the omasum and finally reaches the abomasum (the true stomach) for chemical digestion.