Kerala Syllabus Class 9 Biology Model Question Paper Set 5 English Medium

Teachers recommend solving Kerala Syllabus 9th Standard Biology Question Paper Set 5 to improve time management during exams.

Kerala Syllabus Std 9 Biology Model Question Paper Set 5 English Medium

Time: 1½ Hours
Max Score: 40 Marks

Instructions:

• First 15 minutes is given as cool off time. This time is to be spend for reading and understanding the questions.
• Answer the questions according to the directions.
• Score and time to be considered while answering.

I. Answer any 4 from questions 1 to 5. Each carries 1 score (4 × 1 = 4)

Question 1.
Plants grow in water as well as on land. Who are the producers in the ocean and other water bodies?
Answer:
Aquatic plants include larger plants, or macrophytes, and microscopic algae, or phytoplankton. These are the primary producers in the ocean and other water bodies.

Question 2.
The small intestine involves mechanical processes, namely ……………….. and ………………… to help in
the movement of food and the blending of food with digestive fluids.
Answer:
Peristalsis and Segmentation

Question 3.
What is the function of the small intestine?
Answer:
The small intestine is responsible for the digestion and absorption of nutrients from food.

Question 4.
List the two major stages involved in cellular respiration.
Answer:

• Glycolysis
• Krebs cycle

Question 5.
Which are the two main categories of metabolic processes?
Answer:
The two main categories of metabolic processes are anabolism and catabolism.

II. Answer any 4 from questions 6 to 10. Each carries 2 score (4 × 2 = 8)

Question 6.
The exchange of oxygen from the air which has entered the alveolus into the blood, and the exchange of carbon dioxide into the alveolus from the blood is called the alveolar exchange of gases.’
a) What are the characteristic features of the walls of the alveolus and blood capillaries?
b) What is the importance of moisture in the wall of the alveolus?
Answer:
a) The walls of the alveoli are very thin, which makes it easier for oxygen and CO₂ to pass between the alveoli and very small blood vessels (capillaries). Both are made up of a single layer of cells.

b) Moisture is important for gas exchange because, in order for oxygen and carbon dioxide to effectively cross the alveoli membrane, they must dissolve in an aqueous-like solution. With the right amount of moisture, gas exchange occurs properly.

Question 7.
Your school health club is conducting an awareness class on the topic ‘Bad habits and Health of the heart’. Mention any four points that to be included in the awareness class.
Answer:
Points to be included in the awareness class,

• 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. (Any four)

Question 8.
a) Name the scientist who explained the reactions in the dark phase of photosynthesis,
b) Complete the illustration by including the reactants and products of photosynthesis.

Answer:
a) Melvin Calvin

Question 9.
“Stomata remain open in the day time and closed at night.” Give the reason.
Answer:
Photosynthesis occurs during the day and thus stomata are open to supply the carbon dioxide required for the process. The stomatal openings remain closed at night as photosynthesis is not conducted without sunlight. They are closed to prevent water loss via the stomatal pores.

Question 10.
Complete the illustration related to photosynthesis suitably.

Answer:
i) Light Phase
ii) Water

III. Answer any 4 from questions 11 to 15. Each carries 3 scores (4 × 3 = 12)

Question 11.
Observe the figure and answer the following questions.

a) Why is the dialyis fluid removed from the dialysis unit in due course of time?
b) When is kidney transplantation required?
Answer:
a) If the dialysis fluid is not removed properly, it can cause swelling in blood vessels and increase your blood pressure, which makes your heart work harder. Too much fluid can build up in the lungs, making breathing difficult. Hemodialysis removes fluid as the blood is filtered through the dialysis machine.

b) Kidney transplantation is done when a person whose kidneys no longer function properly.

Question 12.
Observe the figure and answer the questions.

a) Which is the cell organelle?
b) Identify and write the parts A and B.
c) Name the two steps in the process of food formation (photosynthesis) that take place in chloroplasts?
Answer:
a) Chloroplast
b) A – Grana,
B – Stroma lamellae
c) Light phase, Dark phase.

Question 13.
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.
b) Do all the nutrients absorbed from the small intestine have the same path? Explain.
Answer:
a) A – Portal vein, B – Hepatic vein, C – Venacava

b) No. Nutrients like amino acids and glucdse are absorbed into the blood capillaries of the villus and are transported to the liver through the portal vein. Then they are carried to vena cava through hepatic vein. Substances like fatty acid and glycerol are absorbed by the lacteal of villus. They are carried to vena cava by lymph vessels. Vena cava carries all these nutrients to the heart.

Question 14.
a) Mention the role of haemoglobin in respiration.
b) Write any two healthy habits that can be followed to prevent anaemia.
Answer:
a) Haemoglobin is an iron-containing proteinaceous pigment which imparts red colour to the red blood cells (RBCs). Structurally haemoglobin can bind with respiratory gases like O₂ and CO₂ and it helps in the transportation of these gases to and from the cells.

b)

• Eat foods rich in iron and B vitamins.
• Eat fruits and vegetables high in vitamin C, which helps your body absorb iron.

Question 15.
The kidneys filter unwanted substances from the blood and produce urine to excrete them. There are three main steps for urine formation and these processes ensure that only waste and excess water are removed from the body.
a) What are the three main steps for urine formation?
b) Name the diseases that may caused due to abnormal amounts of glucose and calcium oxalate crystals in urine.
c) What are the major components of urine?
Answer:
a) Steps for urine formation,

• Glomerular filtration (Ultrafiltration)
• Reabsorption
• Secretion

b) Abnormal amount of glucose – Diabetes Abnormal amount of Calcium oxalate crystals – Kidney stone

c) Water, urea, sodium chloride, potassium chloride, calcium salts, phosphate, uric acid, creatinine, etc. are’the components of urine.

IV. Answer any 4 from questions 16 to 20. Each carries 4 scores (4 × 4 = 16)

Question 16.
Prepare a short note on how hemodialysis is done.
Answer:
Hemodialysis is a process of filtering the blood of a person whose kidneys are not working normally. Hemodialysis helps control blood pressure and balance important minerals, such as potassium, sodium, and calcium, in your blood.

In this process, blood with a high quantity of waste materials is passed to the dialysis unit after adding heparin to prevent coagulation. When blood flows through the dialysis unit the waste materials in the blood diffuse into the dialysis fluid. This fluid is removed in due course. Antiheparin is added to the purified blood and is returned to the body.

Question 17.
One cardiac cycle is known as one heartbeat.
a) Which are the phases included in a cardiac cycle?
b) Why SA node is known as the pacemaker?
c) Expand ECG.
d) Define pulse.
Answer:
a)

• Atrial systole
• Ventricular systole
• Joint diastole

b) It is the SA node in the wall of the right atrium that sends out the electrical signals that make the heart chambers contract. So, they are known as the Pacemaker.

c) Electrocardiogram (ECG)

d) The wave-like movement formed due to the contraction and relaxation of the heart is felt throughout the walls of the arteries is pulse.

Question 18.
Write the role of each of the following in the exchange of gases.
a) Plasma
b) RBC
c) Haemoglobin
d) Tissue fluid
Answer:
a) Plasma: The cells need oxygen for metabolism, which creates carbon dioxide as a waste product. The carbon dioxide is absorbed from the cells by the blood plasma (some of it binds to hemoglobin too) and is transported back to the lungs in the bloodstream.

b) RBC: Oxygen molecules attach to red blood cells, which travel back to the heart. At the same time, the carbon dioxide molecules in the alveoli are blown out of the body the next time a person exhales.

c) Haemoglobin: Haemoglobin is a molecule that is responsible for carrying almost all of the oxygen in the blood. It is composed of four subunits, each with a heme group and a globin chain. A single haemoglobin molecule can carry four 02 molecules along with the blood.

d) Tissue fluid: It is also called lymph or interstitial fluid helps to bring oxygen and nutrients to cells and to remove waste products from them.

Question 19.
Mangrove forests help in controlling Tsunamis to some extent.
a) Who is the Keralite environmental activist who made us aware of the ecological importance of mangrove forests?
b) What is the ecological importance of mangrove forests?
c) Mention any value-added product of the given economically important plant. Coconut tree –
d) List the economically important plants.
Answer:
a) Kallen Pokudan

b)

• They are a repository of biodiversity.
• They are a source of fish wealth.

c) Coconut tree – Coconut oil.

d)

• Coconut
• Rubber
• Coffee plant
• Tea plant

Question 20.
a) How does the food we swallowed enter the oesophagus properly without entering the trachea? Explain?
b) What do you mean by peristalsis?
c) What are the nutrients we get from food?
Answer:
a) The Tongue compresses the food into balls with the help of the palate. That time, Uvula closes the nasal cavity that opens to the pharynx and the trachea tilts up and it is closed by the epiglottis.

b) Peristalsis is the wave like movement of the oesophagus, stomach and intestines, that facilitates the movement of food through the digestive tract and helps to mix the food with digestive juices.

c) Carbohydrate, Protein, fat, Minerals, vitamins & water.