A thorough understanding of Kerala Syllabus 9th Standard Biology Textbook Solutions Chapter 2 Digestion and Transport of Nutrients Notes Questions and Answers English Medium can improve academic performance.
SCERT Class 9 Biology Chapter 2 Notes Questions and Answers Digestion and Transport of Nutrients
Std 9 Biology Chapter 2 Notes Pdf Kerala Syllabus English Medium Solutions Questions and Answers
Class 9 Biology Chapter 2 Let Us Assess Answers Digestion and Transport of Nutrients
Question 1.
Which one of the following is related to the digestion of Fat?
a) Protease
b) Lipase
c) Amylase
d) Carbohydrase
Answer:
b) Lipase
Question 2.
An illustration related to the circulatory system of human beings is given below. Analyse it and answer the questions.
a) Which letter indicates Pulmonary artery?
Answer: A
b) Which blood vessel is indicated by the letter D?
Answer: Aorta
c) Does the blood that has entered the ventricles return to the atria? Why?
Answer:
No, the blood do not flow back to the atria. Because, tricuspid valve and bicuspid valve prevents the back flow of blood from ventricles to atria.
d) What is the importance of double circulation in human?
Answer:
The same amount of blood passes through the heart twice. This type of circulation is called double circulation. It includes pulmonary circulation and systemic circulation. Double circulation helps to maintain the level of oxygen.
Question 3.
A flowchart on the path of nutrients is given below. Observe it and answer the questions.
a) Name the blood vessels indicated by the letters A, B and C. A, B,C
Answer:
A – Portal vein
B – Hepatic vein
C – Venacava
b) Do all the nutrients absorbed from the small intestine have the same path? Explain.
Answer:
Nutrients like amino acids and glucose are absorbed into the blood capillaries of the villus and are transported to liver through portal vein. Then they are carried to venacava through hepatic vein. Substances like fatty acid and glycerol are absorbed by lacteal of villus. They are carried to venacava by lymph vessel. Venacava carries all these nutrients to the heart.
Question 4.
Which among the following processes takes place by utilising energy?
a) Entry of water into the root cells.
b) Entry of sucrose into the sieve tube.
c) Loss of water from leaves through transpiration.
d) Conduction of water molecules through xylem tubes.
Answer:
b) Entry of sucrose into the sieve tube
Question 5.
Redraw the figure given below, name and label the parts based on the indicators.
a) Part where odontoblast cells are seen
Answer: Pulp cavity
b) Tissue that holds the tooth in the gum.
Answer: Cementum
c) The living tissue by which tooth is made.
Answer: Dentine
Extended Activities
Question 1.
Conduct an awareness class on the topic ‘Bad habits and health of the heart’.
Answer:
Main Points
- Heart disease is the leading cause of death globally.
- While some risk factors are uncontrollable (age, genetics), many lifestyle habits significantly influence heart health:
- Excessive saturated and trans fats raise bad cholesterol, clogging arteries.
- High sodium intake increases blood pressure, putting strain on the heart.
- A sedentary lifestyle increases the risk of obesity, diabetes, and heart disease
- Smoking increases the risk of blood clots and heart attacks.
- Limit saturated and trans fats, processed foods, and added sugars
- Regular exercise strengthens your heart muscle and improves blood flow.
- Ensure adequate sleep for better overall health and stress management.
Question 2.
Organize a nutritious food fest under the auspices of the school health club using locally available food items.
Answer:
Digestion and Transport of Nutrients Class 9 Notes Questions and Answers Kerala Syllabus
Question 1.
Which are the different stages of nutrition?
Answer:
- Ingestion
- Mechanical Digestion
- Chemical Digestion
- Absorption
- Transport
- Egestion of digestive waste
Question 2.
Compare the nutritional processes of amoeba, a unicellular organism and hydra, a multicellular organism and complete the table.
| Hints | Amoeba | Hydra |
| Body structure | Unicellular | |
| Means to help ingestion | ||
| Part where digestion takes place | Inside the cell | |
| Egestion of digestive wastes |
Answer:
| Hints | Amoeba | Hydra |
| Body structure | Unicellular | Multicellular |
| Means to help ingestion | Pseudopodia | Mouth |
| Part where digestion takes place | Inside the cell | Outside the cell |
| Egestion of digestive wastes | Through the cell surface | Through the mouth |
Question 3.
Which are the parts where mechanical digestion takes place?
Answer:
- Mouth
- Stomach
- Small intestine
Question 4.
How does mechanical digestion take place in these parts? prepare a note based on the indicators.
Indicators:
- Structure of tooth.
- Mechanical digestion in mouth, stomach and small intestine.
Answer:
Teeth facilitate the process of breaking down food into smaller pieces and grinding it during chewing. Enamel is the hardest substance in the human body, serving as the non-living outer covering of the tooth. Beneath the enamel is dentine, a living tissue that forms the bulk of the tooth. The innermost part of the tooth is the pulp cavity, which contains soft connective tissue called pulp, along with blood vessels, nerves, and odontoblast cells. The tooth is anchored in the gum socket by cementum, a calcium-containing connective tissue.
The strong peristalsis occurring in the stomach transforms food into a paste form. The circular muscles of the stomach maintain food within the stomach for a sufficient duration. The small intestine involves mechanical processes, namely peristalsis and segmentation, to help in the movement of food and the blending of food with digestive fluids.
Question 5.
What are the things to be taken care for proper dental care? Conduct an interview with a doctor, prepare a poster and exhibit it.
Answer:
Interview
Interviewer: What are the most important things people can do to maintain a good oral health?
Doctor:
- Brush your teeth twice a day
- Flossing once a day removes plaque and food particles from between the teeth, where a brush can’t reach
- Schedule dental checkups and cleanings at least once a year.
Interviewer: Are there any additional tips you recommend for optimal dental health?
Doctor:
- Limit sugary drinks and foods
- Don’t use tobacco products
- Drink plenty of water
- Consider using mouthwash
Poster
Question 6.
Why doesn’t food enter trachea while swallowing it?
Answer:
Tongue compresses the food into balls with the help of palate. Uvula closes the nasal cavity that opens to the pharynx. Posterior part of the tongue allows food to move over the epiglottis into the oesophagus. Trachea rises up and is closed by the epiglottis.
Question 7.
What is the reason for saying that one should not talk while eating food? Find out.
Answer:
Talking while eating can cause food to enter the trachea instead of oesophagus. This will trigger coughing or choking.
Question 8.
How far is the structure of villus suitable for the absorption process? Prepare note according to the indicators.
Indicators:
- Villus and surface area of absorption.
- Lacteal and absorption.
- Blood capillaries and absorption.
Answer:
Villi increase the surface area of absorption of nutrients to a great extent within the small intestine. Absorption of simple nutrients and 90 percent of water takes place through villi. Villi are lined with single-layered epithelial cells, which are the primary surface for nutrient absorption.
Blood capillaries within the villus, formed from an arterial branch, absorb glucose, fructose, galactose, and amino acids, and then unite to form veins that exit the villus. Additionally, the lacteal, a branch of the lymph vessel, absorbs fatty acids and glycerol into the lymph.
Question 9.
Complete the illustration related to the blood components.
Answer:
Question 10.
Find out the functions of different proteins in plasma.
Answer:
Albumin – Regulates blood pressure
Globulin – Helps in defence
Fibrinogen – Plays a major role in the coagulation of blood
Question 11.
How is the quantity of tissue fluid regulated in the space between cells? Find out.
Answer:
Along with the formation of tissue fluid, it absorbs into the lymph capillaries. So there is no increase of pressure in the intercellular space.
Question 12.
Complete the flowchart using the hints.
Hints:
- Portal vein
- Lacteal of villus
- Amino acids
- Glycerol
- Hepatic vein
- Lymph vessel
Answer:
Question 13.
Which are the phases included in a cardiac cycle?
Answer:
- Atrial systole
- Ventricular systole
- Joint diastole
Question 14.
How the function of heart is maintained in people with a functionless pacemaker. Find out.
Answer:
In people with functionless pacemaker, artificial pacemaker is implanted for the functioning.
Question 15.
Apart from the wrist, which are the other parts of the body where we can feel pulse? Find out.
Answer:
Neck, Groin, Foot
Question 16.
Complete the chart
| SI . No | Name of Children | Rate of heart beat | Pulse rate | ||
| At rest | After doing exercise | At rest | After doing exercise | ||
| 1 | |||||
| 2 | |||||
Answer:
| SI No | Name of Children | Rate of heart heat | Pulse rate | ||
| At rest | After doing exercise | At rest | After doing exercise | ||
| 1. | Megha | 72/m in | 120/min | 72/min | 120/min |
| 2. | Nikhil | 74/min | 125/min | 74/min | 125/min |
Question 17.
What is the reason for variations of blood pressure? How does it affect the body? Find out.
Answer:
The normal rate of blood pressure is 120/80 mmHg. The disease condition in which the blood pressure increases above the normal rate is called hypertension. This happens due to many reasons. Unhealthy habits such as excess use of salt and fat, smoking, lack of exercise etc. The condition in which the blood pressure rate goes below the prescribed rate is called hypotension. These hypotension and hypertension may lead to stroke or heart attack.
Question 18.
How does the body utilise each nutrient? Find out.
Answer:
Carbohydrates are broken down into simple sugars in the digestive system. Glucose enters the bloodstream and is transported to cells, where it’s used for immediate energy production or stored for later use as glycogen in the liver and muscles.
Proteins are broken down into amino acids during digestion. Amino acids are then absorbed into the bloodstream and used to build, repair, and maintain various body structures and functions.
Fats are broken down into fatty acids and glycerol during digestion. Fatty acids are then transported to cells for energy storage or used to build cell membranes and signaling molecules.
Vitamins are absorbed in small amounts from food and transported throughout the body. They work in conjunction with enzymes to regulate numerous metabolic processes.