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Digestive and Respiratory System Questions for Competitive Exams. We covered all the Digestive and Respiratory System Questions for Competitive Exams in this post for free so that you can practice well for the exam.
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Digestive and Respiratory System Questions for Competitive Exams
The enzyme that breaks down fats into fatty Acids and glycerol, known as steapsin, is released by
A) Stomach
B) Pancreas
C) Small intestine
D) Large intestine
Option b – Pancreas
Choose the enzyme that digests proteins
A) Lipase
B) Amylase
C) Collagen
D) Pepsin
Option d – Pepsin
Which statements about human enzymes are accurate? Statement A: Maltase is found in saliva and converts maltose into glucose. Statement B: Amylase is found in saliva and helps change starch into sugars.
A) Neither A nor B
B) Only A
C) Both A and B
D) Only B
Option d – Only B
Pick the correct sequence of the human Food canal from start to finish
A) Mouth cavity → Oesophagus → Stomach → Large intestine → Small intestine → Rectum → Anus
B) Mouth cavity → Oesophagus → Stomach → Small intestine → Large intestine → Anus → Rectum
C) Mouth cavity → Oesophagus → Stomach → Large intestine → Small intestine → Anus → Rectum
D) Mouth cavity → Oesophagus → Stomach → Small intestine → Large intestine → Rectum → Anus
Option d – Mouth cavity → Oesophagus → Stomach → Small intestine → Large intestine → Rectum → Anus
In boys, the enlarged larynx appears as a visible bump at the front of the throat called
A) Adrenaline
B) Kanthamani (Adam’s apple)
C) Corn
D) Gullet
Option b – Kanthamani (Adam’s apple)
The conversion of pyruvate to lactic Acid and energy in the absence of oxygen happens in
A) Bacteria
B) Mitochondria
C) Yeast
D) Human muscle cells
Option d – Human muscle cells
Which of these statements about breathing is true? I. Regular practice of breathing exercises (pranayama) can enhance lung capacity. II. During inhalation, the ribs move upward and outward while the diaphragm moves downward.
A) Both I and II
B) Only II
C) Only I
D) Neither I nor II
Option a – Both I and II
What percentage of carbon dioxide is present in exhaled air from human lungs?
A) 3.2%
B) 5.9%
C) 4.4%
D) 2.3%
Option c – 4.4%
The Network of air passages for gas exchange in insects is called
A) Gills
B) Diaphragm
C) Spiracles
D) Tracheae
Option d – Tracheae
Which organ lies between the two lungs?
A) Thymus
B) Pituitary
C) Pineal
D) Hypothalamus
Option a – Thymus
What causes the formation of dental plaque?
A) Clumps of bacteria and Food particles adhering to teeth
B) Saliva sticking to the pulp
C) Bacteria acting on sugars to produce Acids
D) Acids directly attaching to teeth
Option a – Clumps of bacteria and Food particles adhering to teeth
Which substance erodes the enamel of teeth?
A) Toothpaste
B) Acids generated by bacteria
C) Saliva
D) Soft toothbrush
Option b – Acids generated by bacteria
Which structure keeps the respiratory airway from collapsing?
A) Ribs
B) Cartilage rings
C) Spine
D) Trachea
Option b – Cartilage rings
During cellular Respiration, how many oxygen molecules react with a single glucose Molecule?
A) Five
B) Four
C) Six
D) Seven
Option c – Six
Some fish breathe by swallowing water. They do so
A) More times per minute than animals that breathe air
B) Faster when near the water surface
C) Fewer times per minute than animals that breathe air
D) More slowly when living in fast-flowing rivers
Option a – More times per minute than animals that breathe air
Besides lungs, frogs can also respire through their
A) Tracheae
B) Spiracles
C) Gills
D) Smooth, moist skin
Option d – Smooth, moist skin
All the following statements about human Respiration are correct except one. Pick the incorrect option.
A) The ribs move inward while the diaphragm rises.
B) The ribs lift upward and the diaphragm flattens.
C) The chest cavity expands.
D) Air enters the lungs.
Option a – The ribs move inward while the diaphragm rises.
In which part of the digestive system are villi found?
A) Pancreas
B) Oesophagus
C) Small intestine
D) Stomach
Option c – Small intestine
Which of these is not a product of glucose breakdown during Respiration?
A) Ethanol
B) Lactic Acid
C) Water
D) Methanol
Option d – Methanol
In humans, urea is chiefly produced from the metabolism of which nutrient?
A) Fatty Acids
B) Vitamins
C) Amino Acids
D) Glucose
Option c – Amino Acids
Urea formation occurs during the breakdown of
A) Proteins
B) Carbohydrates
C) Lipids
D) Both proteins and carbohydrates
Option a – Proteins
Which pair of enzymes does not function in an acidic Environment?
A) Chymotrypsin and Pepsin
B) Trypsin and Pepsin
C) Pepsin and Amylase
D) Trypsin and Amylase
Option d – Trypsin and Amylase
The longest section of the human alimentary canal is the
A) Small intestine
B) Stomach
C) Large intestine
D) Rectum
Option a – Small intestine
Identify the incorrect statement about bile secretion from the liver.
A) Bile contains enzymes that break down fats.
B) Bile aids in fat emulsification.
C) Bile neutralizes acidic Food entering from the stomach.
D) Bile makes Food alkaline to assist pancreatic enzymes.
Option a – Bile contains enzymes that break down fats.
The antibacterial substance found in saliva and tears is
A) Ribozyme
B) Lipase
C) Lysozyme
D) Isomerase
Option c – Lysozyme
Which of the following is not a characteristic of xerophytes?
A) Small leaves
B) Numerous stomata
C) Waxy cuticle
D) Sunken stomata
Option b – Numerous stomata
Animal fats primarily consist of
A) Unsaturated fatty Acids
B) Saturated fatty Acids
C) Unsaturated long-chain Alcohols
D) Lipids
Option b – Saturated fatty acids
Proteins are made of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur and phosphorus. The building blocks of proteins are
A) Amino acids
B) Nucleic acids
C) Cellulose
D) Glucose
Option a – Amino acids
The enzyme secreted by the stomach wall to digest proteins is
A) Amylase
B) Chitinase
C) Pepsin
D) Trypsin
Option c – Pepsin
Fat Digestion in the human intestine involves
A) Bile and lipase
B) Bile and pepsin
C) Bile and amylase
D) Trypsin
Option a – Bile and lipase
Glucose breakdown in the cytoplasm results in
A) Pyruvate and energy
B) Pyruvate and carbon dioxide
C) Pyruvate and oxygen
D) Pyruvate and nitrogen
Option a – Pyruvate and energy
Under oxygen-deficient conditions, fermentation in yeast produces
A) ATP + O₂ + Pyruvate
B) ATP + CO₂ + Ethanol
C) ATP + CO₂ + Lactic Acid
D) ATP + O₂ + Acetaldehyde
Option b – ATP + CO₂ + Ethanol
What is the main role of the pancreas in Digestion?
A) Releases surfactants to break lipids into droplets.
B) Stores and releases bile.
C) Secretes lipase, amylase, and protease.
D) Neutralizes stomach acids.
Option c – Secretes lipase, amylase, and protease.
In which part of the human body is cartilage absent?
A) Nose
B) Trachea
C) Bronchiole
D) Knee joint
Option c – Bronchiole
During exercise, muscles produce lactic Acid to
A) Provide extra energy from fats
B) Supply additional oxygen from the lungs
C) Generate extra energy from glucose
D) Provide extra energy from vitamins
Option c – Generate extra energy from glucose
Lactose is made of
A) Glucose only
B) Glucose and Fructose
C) Glucose and Galactose
D) Glucose and Sucrose
Option c – Glucose and Galactose
How many carbon atoms are present in one Molecule of pyruvate?
A) 2
B) 3
C) 4
D) 5
Option b – 3
Which of the following helps repopulate the digestive tract with beneficial microbes that counteract harmful ones?
A) Prosthetics
B) Antibiotics
C) Probiotics
D) Prosythetics
Option c – Probiotics
Which section of the digestive system receives secretions from both the liver and pancreas?
A) Stomach
B) Large intestine
C) Small intestine
D) Gall bladder
Option c – Small intestine
What is the primary role of lipase in the digestive process?
A) Breaking down roughage
B) Digesting emulsified fats
C) Releasing intestinal fluids
D) Breaking down proteins
Option b – Digesting emulsified fats
Which non-digestible dietary component is vital for maintaining digestive Health?
A) Roughage
B) Fats
C) Proteins
D) Carbohydrates
Option a – Roughage
Which substance stored in the gall bladder assists in fat Digestion?
A) Acetic Acid
B) Saliva
C) Bile
D) Mucus
Option c – Bile
The process of absorbing nutrients from digested Food into the bloodstream is called
A) Assimilation
B) Transmission
C) Integration
D) Transfusion
Option a – Assimilation
The pouch located at the meeting point of the small and large intestines is called
A) Condyle
B) Caecum
C) Coccyx
D) Axilla
Option b – Caecum
Which of the following statements about the liver is false?
A) It lies in the upper left portion of the abdomen.
B) It secretes bile stored in the gall bladder.
C) It is the largest gland in the body.
D) It is a reddish-brown organ.
Option a – It lies in the upper left portion of the abdomen.
Which type of Food requires a longer small intestine for proper Digestion?
A) Lamb
B) Eggs
C) Grass
D) Chicken
Option c – Grass
In humans, the Digestion of carbohydrates begins in the
A) Rectum
B) Small intestine
C) Oesophagus
D) Buccal cavity
Option d – Buccal cavity
In ruminant animals like cattle, cellulose is broken down by bacteria in the
A) Rumen
B) Oesophagus
C) Small intestine
D) Large intestine
Option a – Rumen
Which pancreatic enzyme is a medium-sized globular protein functioning as a serine protease?
A) Amylase
B) Trypsin
C) Lipase
D) Pepsin
Option b – Trypsin
Which muscle controls the movement of Food from the stomach to the small intestine?
A) Pectoralis
B) Rectus
C) Gastrocnemius
D) Sphincter
Option d – Sphincter
Which of these is NOT a role of calcium in the human body?
A) Aids in blood clotting
B) Supports Digestion
C) Maintains healthy bones and teeth
D) Assists in muscle contraction
Option b – Supports Digestion
The human small intestine, which is coiled, measures about
A) 1 to 1.5 metres
B) 3 to 3.5 metres
C) 2 to 2.5 metres
D) 7 to 7.5 metres
Option d – 7 to 7.5 metres
Which carbohydrate cannot be digested, does not provide energy, but helps eliminate waste and supports intestinal Health?
A) Starch
B) Fibre
C) Glycogen
D) Sugar
Option b – Fibre
Which large muscular sheet forms the floor of the chest cavity?
A) Diaphragm
B) Larynx
C) Alveoli
D) Duodenum
Option a – Diaphragm
Which organ releases hydrochloric Acid to kill harmful bacteria?
A) Heart
B) Brain
C) Stomach
D) Kidney
Option c – Stomach
Which substance makes acidic Food from the stomach alkaline?
A) Gastric juice
B) Pepsin
C) Hydrochloric Acid
D) Bile juice
Option d – Bile juice
The inner surface of the small intestine contains finger-like projections known as
A) Villi
B) Lumps
C) Myomas
D) Benign
Option a – Villi
Which enzyme is necessary for the Digestion of fats?
A) Lipase
B) Trypsin
C) Zymase
D) Invertase
Option a – Lipase
Food travels through which organ before entering the intestines?
A) Mouth → Rectum
B) Windpipe → Food pipe
C) Stomach → Rectum
D) Oesophagus → Stomach
Option c – Oesophagus → Stomach
We covered all the Digestive and Respiratory System Questions for Competitive Exams above in this post for free so that you can practice well for the exam.
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