CLASS 9 BIOLOGY
Questions 1 to 6. Answer any five only. 1 score each. (5×1=5)
- Complete the table.
|Organism||Mechanism of locomotion|
- Select the correct answer.
Which of the following is not a peculiarity of erythrocytes (RBCs).
(A) Colourless (B) Disc -shaped
(C) Nucleus is absent
(D) Transport of respiratory gases.
- Find the missing item in the second pair on the basis of the relationship between the items in the first pair. Write the relationship between the items also.
Lungs: Expels carbon dioxide.
- What is hydrotropism?
- Complete the statement.
……………. carries blood from the heart to the lungs.
- Find the odd one in the group. Write the peculiarity of the others.
Stem grows towards light, Root grows towards gravity, Pollen tube grows to the ovary, Flower buds open.
- What is meant by interphase? What are the changes that occur in interphase?
- Given below are the symptoms of a kidney disease.
Anaemia Loss of weight Dizziness, Suffocation Diarrhoea.
(a) Identify the disease.
(b) How does it occur?
- Identify the correct pairs.
(a) Inspiration- Diaphragm bends.
(b) Expiration- Volume of thoracic cavity increases.
(c) Inspiration- Ribs rise
(d) Expiration- The pressure in the thoracic cavity rises above the atmospheric pressure.
- Ravi’s arm ached after writing notes for two hours continuously. He rested for some time, and he got relieved of the pain. Explain the phenomenon.
- Skin: Expels excess water and salts through sweat.
Excretory organs and their functions.
- Roots grow in the direction of water.
- This is positive hydrotropism.
- The growth of the stem away from water is called negative hydrotropism.
- Pulmonary artery
- Flower buds open; The others are tropic movements.
- The phase at which a cell prepares for division is called interphase.
Changes: Genetic material in the chromatin reticulum duplicates.
Cell organelles and cytoplasm increase.
- (a) Uremia
(b) Urea and other wastes accumulate in the blood due to the malfunctioning or non functioning of both the kidneys.
- c, d
- Since Ravi worked continuously for a long time, lactic acid accumulated in his muscles due to anerobic respiration. This raised the acidity in the muscles. Due to this, the action of many enzymes associated with muscle contraction was slowed down temporarily. This condition is called muscle fatigue. During rest the lactic acid was removed from the muscles. So Ravi got rid of the pain.