Teachers recommend solving Kerala Syllabus 9th Standard Biology Question Paper Set 3 to improve time management during exams.
Kerala Syllabus Std 9 Biology Model Question Paper Set 3 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.
What are some examples of molecules that can easily pass through plasma membrane?
Answer:
Water, oxygen, and carbon dioxide
Question 2
……………….. is a calcium containing connective tissue that holds the tooth in the socket of the gum.
Answer:
Cementum
Question 3.
The double-layered membrane that surrounds and protects the heart.
Answer:
Pericardium
Question 4.
Complete the illustration suitably.
Answer:
Lactic acid.
Question 5.
Name the pores present at the tip of the grass leaves to eliminate excess water.
Answer:
Hydathodes.
II. Answer any 4 from questions 6 to 10. Each carries 2 score (4 × 2 = 8)
Question 6.
Differentiate between alveolar exchange and systemic exchange of gases.
Answer:
Alveolar exchange is the exchange of oxygen from the air which has entered the alveolus, into the blood and carbon dioxide into the alveolus from the blood.
Systemic gas exchange is the movement of respiratory gases between blood in systemic capillaries and systemic cells.
Question 7.
Anaerobic respiration takes place in human muscles under certain circumstances.
a. Give reason for this.
b. Name the product of this process.
Answer:
a) When oxygen availability decreases due to strenuous exercise or work, anaerobic respiration takes place in muscle cells.
b) Lactic acid.
Question 8.
Complete the flow chart related to metabolism.
Answer:
Question 9.
“A substantial amount of oxygen in the atmosphere is released by producers in the ocean. Pollution is the most serious threat the marine ecosystem faces.”
Write any two steps to be taken to prevent ocean pollution.
Answer:
Reduce plastic production & waste, Improve wastewater systems, Use eco-friendly products, Reduce chemical pollution (Any two)
Question 10.
Observe the figure and answer the following questions.
a) What is lymph?
b) What is the role of the lymphatic system in digestion?
Answer:
a) Lymph is a fluid derived from tissue fluid that enters specialized vessels called lymph capillaries.
It differs from blood in that it lacks red blood cells and large protein molecules.
b) The lymphatic system plays a vital role in transporting certain products of fat digestion and fat soluble vitamins absorbed from the small intestine. These are transported through lymph vessels instead of directly entering the bloodstream.
III. Answer any 4 from questions 11 to 15. Each carries 3 scores (4 × 3 = 12)
Question 11.
Arrange the given steps of blood circulation in the correct order, starting from Right atrium.
• Blood from different parts of the body reaches the right atrium.
• Blood passes through the pulmonary artery to the lungs.
• Right ventricle contracts.
• Blood reaches the left atrium through the pulmonary veins.
• Right ventricle receives blood through the tricuspid valve.
• Left ventricle receives blood through the bicuspid valve.
Answer:
• Blood from different parts of the body reaches the right atrium.
• Right ventricle receives blood through the tricuspid valve.
• Right ventricle contracts.
• Blood pass through the pulmonary artery to lungs.
• Blood reaches the left atrium through the pulmonary veins.
• Left ventricle receives blood through the bicuspid valve
Question 12.
Complete the flowchart using the hints.
Hints:
• Portal vein
• Lacteal of villus
• Amino acids
• Glycerol
• Hepatic vein
• Lymph vessel
Answer:
Question 13.
Give reasons for the following.
a) Plasma membrane is known as a selectively permeable membrane.
b) When raisins are placed in freshwater, they will bulge.
c) Plants store glucose in the form of starch in leaves.
Answer:
a) The plasma membrane is called a selectively permeable membrane, because, it allows only
certain molecules to pass through it.
b) When raisins are placed in fresh water, they will bulge, because a high amount of water enters into it. This is because of the movement of water molecules from higher concentration to lower concentration.
c) Since glucose is readily soluble in water, it can not be stored. Hence it is converted into insoluble starch in plants.
Question 14.
Observe the figure related to breathing and answer the questions.
a) Identify the step of breathing.
b) Name the parts indicated as X and Y.
c) How does the combined action of X and Y help in this process?
Answer:
a) Inspiration
b) X – Intercostal muscles, Y – Diaphragm
c) During inspiration, air enters the lungs by the contraction of both the intercostal muscles and the diaphragm.
Question 15.
Complete the following table related to cellular respiration suitably.
| Indicator | Glycolysis | Kreb’s cycle |
| Location | (i) …………………….. | (ii) …………………….. |
| Need of oxygen | (iii) …………………….. | (iv) …………………….. |
| Process | (v) ……………………..is converted into Pyruvic acid | Pyruvic acid is converted to (vi) …………………….. |
Answer:
(i) Cytoplasm
(ii) Mitochondria
(iii) No need of Oxygen
(iv) Oxygen required
(v) Glucose
(vi) Carbon dioxide, water and 28 ATP.
IV. Answer any 4 from questions 16 to 20. Each carries 4 scores (4 × 4 = 16)
Question 16.
Classify the given items under two suitable headings in the given table below.
Calcitonin, Sucrase, Progesterone, Salivary amylase, Testosterone, Lipase, Pepsin, Thymosine, Thyroxine
| …………………….. | …………………………. |
Answer:
| Enzymes | Hormones |
| 1. Salivary amylase in saliva | 1. Sex hormone – Testosterone, Estrogen, Progesteron |
| 2. Pepsin in the gastric juice | 2. Thyroxine |
| 3. Sucrase | 3. Calcitonin |
| 4. Lipase | 4. Thymosin |
Question 17.
“Nature and humans are receiving countless services from plants. Most plant parts have economic importance in one way or the other.”
a) Mention the economic importance of plants.
b) List any three services provided by plants to the biosphere.
Answer:
a) Besides food and medicines, plants and trees play an essential role in industries. Many raw
materials are obtained from plants and giant trees, and used to produce various industrial products, including paper, spices, cosmetics, pencils, rubber, furniture, and other household products.
b)
- Provide food
- Provide oxygen
- Decrease the level of global warming by the absorption of CO2.
- Mitigate natural calamities
- Act as the storehouse of biodiversity
- Provide economically important resources (Any three).
Question 18.
Transport in plants takes place through two types of complex tissues in plants, namely Xylem and Phloem.
a) What are the main forces that drive water movement through the xylem?
b) How does water loss from leaves through transpiration contribute to water movement?
Answer:
a) The main forces responsible for water movement through thexylem are cohesion and adhesion:
Cohesion: The attraction between water molecules due to hydrogen bonding. This allows water molecules to form a continuous chain that pulls water upwards.
Adhesion: The attraction of water molecules to the walls of the xylem tubes. This helps create a continuous water column that resists breaking.
b) Transpiration is the loss of water vapor from leaves through tiny pores called stomata. As water evaporates from leaves, it creates a suction force that pulls water upwards through the xylem from the roots. This “pull” is aided by the cohesive and adhesive properties of water.
Question 19.
Observe the figure and answer the questions.
i) Which is the method of treatment indicated in the figure?
ii) When is this treatment needed?
iii) Write the stages of this treatment in correct order.
Answer:
i) Haemodialysis
ii) Haemodialysis is the process proposed by modern medicine for the removal of wastes from the blood when both kidneys become non-functional
iii) a) Blood which contains wastes from the artery is pumped into the dialysis unit. Heparin is
added to prevent coagulation.
b) Wastes from the blood are diffused into the dialysing fluid when it flows through the cellophane tube.
c) Purified blood is pumped back to the veins through another tube.
Question 20.
Redraw the diagram, label the parts, and write their functions.
Answer:
a) Kidney: They remove waste products from the blood and produce urine. Kidneys control the levels of many substances in the blood. Kidneys help to control our blood pressure.
b) Ureters: The ureters are the part of the urinary system, The ureter’s role in the process is to carry urine from the kidneys to the bladder. Contractions in the ureter, force urine away from the kidneys and into the bladder.
c) Urinary bladder: A hollow organ that stores urine from the kidneys before disposal by urination.
Urethra: The urethra acts as a passage to expel urine from the urinary bladder to the outside of the body.