- (a) Sublingual
- (b) Lachrymal
- (c) Submaxillary
- (d) Parotid
Answer:
(b) Lachrymal
Lachrymal gland produces tears.
- (a) carbohydrates
- (b) proteins
- (c) fats
- (d) sucrose
Answer:
(b) proteins
- (a) Epiglottis
- (b) Glottis
- (c) Hard palate
- (d) Soft palate
Answer:
(a) Epiglottis
- (a) proteins
- (b) sugar
- (c) fats
- (d) carbohydrates
Answer:
(c) fats
- (a) villi
- (b) liver
- (c) nephron
- (d) ureter
Answer:
(c) nephron
- (a) Urea
- (b) Protein
- (c) Water
- (d) Salt
Answer:
(b) Protein
- (a) ureter
- (b) urethra
- (c) vas deferens
- (d) scrotum
Answer:
(b) urethra
Correction made:
Original answer incorrectly marked vas deferens.
- (a) Ovary
- (b) Uterus
- (c) Testes
- (d) Fallopian tube
Answer:
(c) Testes
- Opening of stomach into intestine is called pylorus.
- Organ helping in mixing food with saliva is tongue.
- Bile secreted by liver is stored in gall bladder.
- Longest part of alimentary canal is ileum.
- Normal human body temperature is about 37°C.
- Largest cell in female body is ovum.
If false, correct the statement.
Answer: False. Correct Statement: Hydrochloric acid in the stomach kills microorganisms. Hydrochloric acid is secreted by the parietal cells of the gastric glands in the stomach and creates an acidic environment with a pH of about 1.5 to 3.5. This highly acidic medium is lethal to most microorganisms that may enter the stomach with food, providing a protective function against bacterial and other microbial infections. Nitric acid is not present in the stomach.
Answer: True. Proteins are broken down into amino acids during digestion. Protein digestion begins in the stomach where the enzyme pepsin breaks proteins into smaller polypeptides in the acidic environment created by hydrochloric acid. The process continues in the small intestine where pancreatic proteases and intestinal peptidases further break down polypeptides into individual amino acids. These amino acids are then absorbed through the intestinal wall into the bloodstream for use in various metabolic processes and protein synthesis throughout the body.
Answer: False. Correct Statement: Hormones are not normally present in significant amounts in glomerular filtrate. The glomerular filtrate contains water, salts, glucose, amino acids, and urea, which are small molecules that can pass through the filtration barrier of the glomerulus. However, hormones are typically large protein molecules or are bound to proteins in the blood, so they cannot pass through the glomerular filter and are retained in the blood. Proteins and blood cells are also absent from the normal glomerular filtrate because they are too large to be filtered. The presence of proteins or hormones in the filtrate would indicate a problem with the filtration barrier.
| Organ | Elimination Product |
|---|---|
| Skin | Sweat |
| Lungs | Carbon dioxide |
| Intestine | Undigested food |
| Kidneys | Urine |
# (a) Excretion and Secretion
| Excretion | Secretion |
|---|---|
| Removal of metabolic wastes | Release of useful substances |
| Removes harmful substances | Helps body functions |
| Example: Urine | Example: Enzymes, hormones |
# (b) Absorption and Assimilation
| Absorption | Assimilation |
|---|---|
| Nutrients enter blood from intestine | Nutrients utilized by cells |
| Occurs in small intestine | Occurs in body tissues |
# (c) Ingestion and Egestion
| Ingestion | Egestion |
|---|---|
| Intake of food | Removal of undigested food |
| Beginning of digestion | End of digestion |
# (d) Diphyodont and Heterodont
| Diphyodont | Heterodont |
|---|---|
| Two sets of teeth | Different types of teeth |
| Milk teeth and permanent teeth | Incisors, canines, premolars, molars |
# (e) Incisors and Canines
| Incisors | Canines |
|---|---|
| Cutting and biting | Tearing and piercing |
| 8 in adults | 4 in adults |
Answer:
Ileum contains millions of finger-like villi.
Each villus contains:
- blood capillaries
- lacteals
These absorb digested nutrients efficiently.
Answer:
Sweat cools body by evaporation.
Sweat contains:
- water
- salts
- urea
Evaporation lowers body temperature.
Answer:
- Maintains water and salt balance
- Regulates pH of blood
- Removes nitrogenous wastes
- Maintains osmotic balance
Answer: Micturition is the process of expulsion of urine from the urinary bladder through the urethra. It is a reflex action that occurs when the bladder becomes full and stretches, triggering sensory receptors that send signals to the spinal cord. These signals then trigger motor neurons that cause the muscles of the bladder wall to contract and the sphincters to relax, allowing urine to be expelled. In adults, micturition is also under voluntary control through the cerebral cortex, allowing conscious regulation of the process.
| Teeth | Function |
|---|---|
| Incisors | Cutting |
| Canines | Tearing |
| Premolars | Crushing |
| Molars | Grinding |
Answer:
Nephron is structural and functional unit of kidney.
Parts of Nephron
- Bowman’s capsule
- Glomerulus
- Proximal convoluted tubule
- Loop of Henle
- Distal convoluted tubule
- Collecting duct
Blood Supply
- Afferent arteriole enters glomerulus
- Efferent arteriole leaves glomerulus
# Parts of Alimentary Canal
- Mouth
- Buccal cavity
- Pharynx
- Oesophagus
- Stomach
- Small intestine
- Large intestine
- Rectum
- Anus
# Mouth and Buccal Cavity
- Teeth chew food
- Tongue mixes saliva
# Teeth
Humans are:
- Diphyodont
- Thecodont
- Heterodont
Dental Formula
# Salivary Glands
- Parotid
- Sublingual
- Submandibular
# Oesophagus
Food moves by:
Peristalsis
# Stomach
- J-shaped muscular organ
- Digests proteins
- Contains gastric juice and HCl
# Small Intestine
Parts:
- Duodenum
- Jejunum
- Ileum
Main site for:
- digestion
- absorption
# Liver
Largest gland.
Produces bile.
# Pancreas
Produces digestive enzymes and hormones.
# Large Intestine
Absorbs water and forms faeces.
Parts:
- Caecum
- Colon
- Rectum
# Structure of Kidney
- Bean-shaped organs
- Located on either side of vertebral column
- Right kidney slightly lower
Internal Structure
Cortex
Outer region
Medulla
Inner region
Contains renal pyramids.
Hilum
Entry point for:
- blood vessels
- nerves
- ureter
# Steps in Urine Formation
# (i) Glomerular Filtration
Blood filtered in glomerulus.
Filtrate enters Bowman’s capsule.
# (ii) Tubular Reabsorption
Useful substances reabsorbed:
- glucose
- amino acids
- water
- salts
# (iii) Tubular Secretion
Waste ions secreted into tubule.
Final urine formed.
# Path of Urine
Assertion: Urea is excreted through kidneys. Reason: Urea is toxic. Answer: (a) Both are true and reason correctly explains assertion. Urea is a nitrogenous waste product formed during protein metabolism in the liver. It is toxic to the body and must be removed to prevent harmful accumulation. The kidneys filter urea from the blood and excrete it in urine, making them the primary organs responsible for urea elimination. This process is essential for maintaining the body's internal environment and preventing the toxic effects of nitrogenous waste.
Assertion: Gonads perform dual functions. Reason: Gonads are primary sex organs. Answer: (b) Both are true, but reason does not correctly explain assertion. Gonads are the primary sex organs that perform two distinct and equally important functions. First, they produce gametes, which are sex cells—sperm in males and eggs in females—necessary for sexual reproduction. Second, gonads secrete sex hormones such as testosterone in males and estrogen and progesterone in females, which regulate secondary sexual characteristics and reproductive processes. The reason that gonads are primary sex organs is true but does not fully explain why they perform dual functions; rather, the dual functions arise from their specialized cellular composition containing both germ cells for gamete production and endocrine cells for hormone secretion.
Answer: Protein digestion in the stomach will be affected. Pepsin breaks down proteins into peptides in the stomach; without pepsin, proteins will not be efficiently cleaved into peptides there, impairing protein digestion and subsequent absorption.
| Vessel | Function |
|---|---|
| Afferent arteriole | Enters glomerulus |
| Efferent arteriole | Leaves glomerulus |
Answer:
Helps diagnose:
- Diabetes
- Kidney disorders
- Liver diseases
- Urinary infections
Answer:
Water helps:
- Maintain hydration
- Regulate body temperature
- Kidney function
- Remove wastes
Answer:
They help:
- improve grip
- prevent slipping
- respond to emotional stress
| Label | Part |
|---|---|
| 1 | Fallopian tube |
| 2 | Ovary |
| 3 | Cervix |
| 4 | Uterus |
| 5 | Vagina |
Teeth and Food Habits
# Carnivores (Lion)
Teeth Features
- Sharp canines
- Sharp molars
- Used for tearing flesh
# Herbivores (Buffalo)
Teeth Features
- Broad molars
- Used for grinding plants
# Important Summary
Digestion
Breakdown of food into simple substances.
Absorption
Occurs in ileum through villi.
Excretion
Removal of nitrogenous wastes.
Kidney
Main excretory organ.
Nephron
Structural and functional unit of kidney.
Micturition
Expulsion of urine.
Human Teeth
- Diphyodont
- Thecodont
- Heterodont
Salivary Glands
- Parotid
- Sublingual
- Submandibular
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