1. Active transport involves
a) movement of molecules from lower to higher concentration
b) expenditure of energy
c) it is an uphill task
d) all of the above
2. Water which is absorbed by roots is transported to aerial parts of the plant through
a) cortex
b) epidermis
c) phloem
d) xylem
3. During transpiration there is loss of
a) carbon dioxide
b) oxygen
c) water
d) none of the above
4. Root hairs are
a) cortical cell
b) projection of epidermal cell
c) unicellular
d) both b and c
5. Which of the following process requires energy?
a) active transport
b) diffusion
c) osmosis
d) all of them
6. The wall of human heart is made of
a) Endocardium
b) Epicardium
c) Myocardium
d) All of the above
7. Which is the sequence of correct blood flow
a) ventricle - atrium - vein - arteries
b) atrium - ventricle - veins - arteries
c) atrium - ventricle - arteries - vein
d) ventricles - vein - atrium - arteries
8. A patient with blood group O was injured in an accident and has blood loss. Which blood group the doctor should effectively use for transfusion in this condition?
a) O group
b) AB group
c) A or B group
d) all blood group
9. ‘Heart of heart’ is called
a) SA node
b) AV node
c) Purkinje fibres
d) Bundle of His
10. Which one of the following regarding blood composition is correct
a) Plasma - Blood + Lymphocyte
b) Serum - Blood + Fibrinogen
c) Lymph - Plasma + RBC + WBC
d) Blood - Plasma + RBC+ WBC +Platelets
1. Transpiration involves evaporative loss of water from aerial parts.
2. Water enters the root cell through a root hair plasma membrane.
3. Structures in roots that help to absorb water are root hairs.
4. Normal blood pressure is 120/80 m Hg.
5. The normal human heartbeat rate is about 72 time per minute.
Section I
1. Symplastic pathway - Leaf
2. Transpiration - Plasmodesmata
3. Osmosis - Pressure in xylem
4. Root Pressure - Pressure gradient
Section I Answer:
1. Symplastic pathway - Plasmodesmata
2. Transpiration - Leaf
3. Osmosis - Pressure gradient
4. Root pressure - Pressure in xylem
Section II
1. Leukemia - Thrombocytes
2. Platelets - Phagocyte
3. Monocytes - Decrease in leucocytes
4. Leucopenia - Blood Cancer
5. AB blood group - Allergic condition
6. O blood group - Inflammation
7. Eosinophil - Absence of antigen
8. Neutrophils - Absence of antibody
Section II Answer:
1. Leukemia - Blood cancer
2. Platelets - Thrombocytes
3. Monocytes - Phagocyte
4. Leucopenia - Decrease in leucocytes
5. AB blood group - Absence of antibody
6. 0 blood group - Absence of antigen
7. Eosinophil - Allergic condition
8. Neutrophils - Inflammation
1. The phloem is responsible for the translocation of food. - True
2. Plants lose water by the process of transpiration.
3. The form of sugar transported through the phloem is glucose. - False
The form of sugar transported through the phloem is sucrose.
4. In apoplastic movement the water travels through the cell membrane and enter the cell.
In apoplastic movement the water travels through the intercellular spaces and walls of the cells.
5. When guard cells lose water the stoma opens.
When guard cells become turgid the stoma opens.
6. Initiation and stimulation of heart beat take place by nerves.
Initiation and stimulation of heart beat take place by muscles.
7. All veins carry deoxygenated blood.
All veins carry deoxygenated blood except pulmonary vein which carries oxygenated blood.
8. WBC defend the body from bacterial and viral infections.
9. The closure of the mitral and tricuspid valves at the start of the ventricular systole produces the first sound ‘LUBB’.
1. Name two layered protective covering of human heart.
Pericardium.
2. What is the shape of RBC in human blood?
Biconcave / disc shaped.
3. Why is the colour of the blood red ?
Presence of red blood cells containing haemoglobin.
4. Which kind of cells are found in the lymph?
White blood corpuscles.
5. Name the heart valve associated with the major arteries leaving the ventricles.
Semilunar valves.
6. Mention the artery which supplies blood to the heart muscle.
Coronary artery.
1. What causes the opening and closing of guard cells of stomata during transpiration?
(i) Stomata are open in the day and closed at night. The opening and closing of the stomata is due to the change in turgidity of the guard cells.
(ii) When water enters into the guard cells, they become turgid and the stoma open. When the guard cells lose water, it becomes flaccid and the stoma closes.
2. What is cohesion?
The force of attraction between molecules of water is called cohesion.
3. Trace the pathway followed by water molecules from the time it enters a plant root to the time it escapes into the atmosphere from a leaf.
There are millions of root hairs on the tip of the root which absorb water and minerals by diffusion. Root hairs are thin walled, slender extension of epidermal cell that increase the surface area of absorption.
Pathway of Water Absorbed by Roots:
Once the water enters the root hairs, the concentration of water molecules in the root hair cells become more than that of the cortex. Thus water from the root hair moves to the cortical cells by osmosis and then reaches the xylem. From there the water is transported to the stem and leaves.
Types of Movement of Water into the Root Cells:
Once water is absorbed by the root hairs, it can move deeper into root layers by two distinct pathways:
(i) Apoplast pathway
(ii) Symplast pathway
(i) Apoplast Pathway :
1. The apoplastic movement of water occurs exclusively through the intercellular spaces and the walls of the cells.
2. This movement is dependent on the gradient.
(ii) Symplast Pathway :
1. In symplastic movement, the water travels through the cells i.e. their cytoplasm; intercellular movement is through the plasmodesmata.
2. Movement is again down a potential gradient.
Transpiration :
(i) Transpiration is the evaporation of water in plants through stomata in the leaves.
(ii) Water evaporates from mesophyll cells of leaves through the open stomata, this lowers water concentration in mesophyll cells.
(iii) As a result, more water is drawn into these cells from the xylem present in the veins through the process of osmosis.
(iv) As water is lost from the leaves, pressure is created at the top to pull more water from the xylem to the mesophyll cells, this process is called transpiration pull.
(v) This extends up to the roots causing the roots to absorb more water from the soil to ensure continuous flow of water from the roots to the leaves.
4. What would happen to the leaves of a plant that transpires more water than its absorption in the roots?
If the leaves of a plant transpire more water than its absorption in the roots, it can lead to the following:
(i) Absorption of water will increase since the cells will require more water to compensate the loss by transpiration.
(ii) The plants may also start wilting. If they are unable to absorb more water from the soil. This can happen in deserts where temperature is high and rate of transpiration will be more but soil will not be rich in water.
5. Describe the structure and working of the human heart.
Structure : Heart is a muscular pumping organ that pumps out the blood into the blood vessels. Contraction of the heart is called systole and relaxation is called diastole.
(i) When the auricles are filled with blood they are in diastole. The tricuspid and bicuspid valves remain closed. This is called atrial diastole.
(ii) When the auricles are full they contract. This leads to opening of tricuspid and bicuspid valves. Blood from right and left auricles is pushed into right and left ventricles respectively. This is called atrial systole.
(iii) Following this the valves are closed the ventricles contract. The deoxygenated blood from right ventricle enters the pulmonary artery and oxygenated blood from left ventricle enters the aorta. This is called ventricular systole.
During this time the auricles are in diastole the atrial systole (0.1 sec), ventricular systole (0.3 sec) and ventricular diastole (0.4 sec) constitute a cardiac cycle.
6. Why is the circulation in man referred to as double circulation?
In our body blood circulates twice through the heart in one complete cycle and it is called double circulation. In double circulation the oxygenated blood do not mix with the deoxygenated blood.
7. What are heart sounds? How are they produced?
(i) The rhythmic closure and opening of the valves cause the sound of the heart.
(ii) The first sound LUBB is of longer duration and is produced by the closure of the tricuspid and bicuspid valves after the beginning of ventricular systole.
(iii) The second sound DUPP is of a shorter duration and produced by the closure of semilunar valves "at the end of ventricular systole.
8. What is the importance of valves in the heart?
(i) Regulate the flow of blood in a single direction. (ii) Prevent back flow of blood.
9. Who discovered Rh factor? Why was it named so?
(i) Rh factor was discovered by Landsteiner and Wiener in 1940.
(ii) It is named as 'Rh' because it was first discovered is Rhesus monkeys.
10. How are arteries and veins structurally different from one another?
S.No : ARTERY : VEIN
1. Distributing vessel : Collecting vessel
2. Pink in colour : Red in colour
3. Deep location : Superficial in location
4. Blood flow with high pressure : Blood flow with low pressure
5. Wall of artery is strong, thick and elastic : Wall of vein is weak, thin and non-elastic
6. All arteries carry oxygenated blood except pulmonary arteries : All veins carry deoxygenated blood except pulmonary veins
7. Internal valves are absent : Internal valves are present
11. 11 Why is the Sinoatrial node called the pacemaker of heart?
(i) The human heart is myogenic in nature. The contraction of the heart is initiated by a specialised portion of the heart muscle called sinoatrial node.
(ii) This is situated in the wall of the right atrium near the opening of the superior venacava.
(iii) It is made up of thin fibres.
(iv) This is called the pacemaker of the heart because it is capable of initiating impulse which can stimulate the heart muscle to contract.
12. Differentiate between systemic circulation and pulmonary circulation.
S.No. : Systemic circulation : Pulmonary circulation
1. It starts from left ventricle and circulates oxygenated blood to various parts of the body. : 1. It starts from the right ventricle to lungs with deoxygenated blood.
2. Ends in a right atrium with deoxygenated blood. : 2. Ends in a left atrium with oxygenated blood.
13. The complete events of cardiac cycle last for 0.8 sec. What is the timing for each event?
Events of cardiac cycle - Total duration 0.8 sec.
a) Atrial systole (Contraction of auricles) - 0.1 sec
b) Ventricular systole (Contraction of ventricles) - 0.3 sec
c) Ventricular diastole (Relaxation of ventricles) - 0.4 sec
Total duration of cardiac cycle - 0.8 sec
1. Minerals cannot be passively absorbed by the roots.
(i) All minerals cannot be passively absorbed by the roots because minerals are present in the soil as charged particles (ions) that cannot move across cell membranes.
(ii) The concentration of minerals in the soil is usually lower than the concentration of minerals in the root. Hence most minerals enter the root by active absorption requiring energy. Hence minerals cannot be passively absorbed by the roots.
2. Guard cells are responsible for opening and closing of stomata.
(i) Stomata are open in the day and closed at night. The opening and closing of the stomata is due to the change in turgidity of the guard cells.
(ii) When water enters into the guard cells, they become turgid and the stoma open. When the guard cells lose water, it becomes flaccid and the stoma closes.
3. The movement of substances in the phloem can be in any direction.
(i) Phloem transports food (sucrose) from a source to a sink. The source is part of the plant that synthesize food, i.e., the leaf, and sink, is the part that needs or stores the food.
(ii) But, the source and sink may be reversed depending on the season, or the plants need.
(iii) The direction of movement in the phloem can be upwards or downwards, i.e., bidirectional.
4. Minerals in the plants are not lost when the leaf falls.
(i) Minerals are remobilised from older dying leaves to younger leaves. eg. Elements like phosphorus, sulphur.
(ii) This phenomenon can be seen in deciduous plants.
(iii) Small amounts of material exchange takes place between xylem and phloem. Hence minerals are not lost when the leaf falls.
5. The walls of the right ventricle are thicker than the right auricles.
(i) The right ventricles have thicker walls to pump out blood with force away from the heart.
(ii) The right auricle is only receiving blood from the Pre caval and Post caval veins. Hence it is thin walled than the ventricle.
6. Mature RBC in mammals do not have cell organelles.
(i) Mammalian RBC lack nucleus and makes the cells biconcave which increase the surface area for oxygen binding.
(ii) Lack of mitochondria allows the RBC to transport all the oxygen to tissues, and loss of endoplasmic reticulum allows more flexibility for RBC to move through the narrow capillaries.
1. How do plants absorb water? Explain.
Answer:
Root Hair-Water Absorbing Unit:
There are millions of root hairs on the tip of the root which absorb water and minerals by diffusion. Root hairs are thin walled, slender extension of epidermal cell that increase the surface area of absorption.
Root Tip with Root Hairs
Pathway of Water Absorbed by Roots :
(i) Once the water enters the root hairs, the concentration of water molecules in the root hair cells become more than that of the cortex.
(ii) Thus water from the root hair moves to the cortical cells by osmosis and then reaches the xylem.
(iii) From there the water is transported to the stem and leaves.
T. S. of the root showing movement of water from soil to xylem
Types of Movement of Water into the Root Cells : Once water is absorbed by the root hairs, it can move deeper into root layers by two distinct pathways:
1. Apoplast pathway
2. Symplast pathway
Apoplast Pathway :
(i) The apoplastic movement of water occurs exclusively through the intercellular spaces and the walls of the cells.
(ii) Apoplastic movement does not involve crossing the cell membrane. This movement is dependent on the gradient.
Symplast Pathway :
(i) In symplastic movement, the water travels through the cells i.e. their cytoplasm; intercellular movement is through the plasmodesmata.
(ii) Water enter the cells through the cell membrane, hence the movement is relatively slower. Movement is again down a potential gradient.
2. What is transpiration? Give the importance of transpiration.
Answer:
Definition : Transpiration is the evaporation of water in plants through stomata in the leaves.
Importance of Transpiration :
(i) Creates transpirational pull for transport of water.
(ii) Supplies water for photosynthesis.
(iii) Transports minerals from soil to all parts of the plant.
(iv) Cools the surface of the leaves by evaporation.
(v) Keeps the cells turgid; hence, maintains their shape.
3. Why are leucocytes classified as granulocytes and agranulocytes? Name each cell and mention its functions.
Answer:
Granulocytes : They contain granules in their cytoplasm. Hence they are called as granulocytes. The granulocytes are of three types.
i. Neutrophils, ii. Eosinophils, iii. Basophils
(i) Neutrophils and its function : These corpuscles form 60% - 65% of the total leucocytes. Their number in increased during infection and inflammation.
(ii) Eosinophils and its function : Their number increases during conditions of allergy and parasitic infections. It brings about detoxification of toxins.
(iii) Basophils and its function : They form 0.5 - 1.0 % of the total leucocytes. They release chemicals during the process of inflammation.
Agranulocytes : Granules are not found in the cytoplasm of these cells.
They are of two types.
(i) Lymphocytes : They form 20 - 25% of the total leucocytes. They produce antibodies during bacterial and viral infections.
(ii) Monocytes : These cells form 5 - 6 % of the total leucocytes. They are phagocytic and can engulf bacteria.
4. Differentiate between systole and diastole. Explain the conduction of heart beat.
Answer:
Systole : Contraction phase of the heart
Diastole : Relaxation phase of the heart
Conduction of heart beat :
(i) Human heart is myogenic in nature. Contraction is initiated by a specialized muscle, the Sino-Atrial (SA) node which is situated in the wall of the right atrium near the opening of the superior vena cava.
(ii) The SA node is broader at the top and tapering below. It is made up of thin fibres.
(iii) SA node acts as the ‘pacemaker’ of the heart because it is capable of initiating impulse which can stimulate the heart muscles to contract.
(iv) Impulse from the SA node spreads as a wave of contraction over the right and left atrial wall pushing the blood through the atrioventricular valves into the ventricles.
(v) The wave of contraction from SA node reaches the AtrioVentricular (AV) node which is stimulated to emit an impulse of contraction spreading to the ventricular muscle via the atrioventricular bundle and the Purkinje fibres.
5. Enumerate the functions of blood.
Answer:
(i) Transport of respiratory gases.
(ii) Transport of digested food materials to the different body cells.
(iii) Transport of hormones.
(iv) Transport of nitrogenous excretory products like ammonia, urea and uric acid.
(v) It is involved in protection of the body and defense against diseases.
(vi) Blood acts as buffer and helps in regulation of pH and body temperature.
(vii) It maintains proper water balance in the body.
Direction: In each of the following questions a statement of assertion (A) is given and a corresponding statement of reason (R) is given just below it. Mark the correct statement as.
a. If both A and R are true and R is correct explanation of A
b. If both A and R are true but R is not the correct explanation of A
c. A is true but R is false
d. Both A and R are false
1. Assertion: RBC plays an important role in the transport of respiratory gases.
Reason: RBC do not have cell organelles and nucleus.
Answers: a. If both A and R are true and R is correct explanation of A
2. Assertion: Persons with AB blood group are called an universal recipients, because they can receive blood from all groups.
Reason: Antibodies are absent in persons with AB blood group.
Answers: a. If both A and R are true and R is correct explanation of A
1. When any dry plant material is kept in water, they swell up. Name and define the phenomenon involved in this change.
Imbibition (i) Imbibition is a type of diffusion in which a solid absorbs water and gets swelled up. E.g: absorption of water by seeds and dry grapes.
2. Why are the walls of the left ventricle thicker than the other chambers of the heart?
(i) The left ventricle has the major function of pumping out blood away from the heart with lot of force such that the oxygenated blood pumped by it should get distributed to all the body parts.
(ii) Aorta is the largest artery which leaves the left ventricle distributing oxygenated blood to the entire body.
(iii) Thus the left ventricular walls are thicker than other chambers of the heart.
3. Doctors use stethoscope to hear the sound of the heart. Why?
(i) A stethoscope is used to detect the sound produced by the internal organs of human body.
(ii) The heart sound is heard by placing the stethoscope on the chest. It is a useful diagnostic tool to identify and localize health problems and diagnose disease.
4. How does the pulmonary artery and pulmonary vein differ in their function when compared to a normal artery and vein?
(i) A normal artery carries (oxygenated) pure blood and a normal vein carries (deoxygenated) impure blood.
(ii) Pulmonary artery is the only artery in our body which carries deoxygenated blood.
(iii) It carries the blood to the lungs for purification from the heart.
(iv) Similarly pulmonary vein leaves the lungs with oxygenated blood and enters the left auricle of the heart, to be supplied to the whole body through left ventricle and aorta.
(v) Thus pulmonary vein is the only vein which carry pure blood.
5. Transpiration is a necessary evil in plants. Explain.
(i) Transpiration is a necessary evil in plants, because transpiration is inevitable, but potentially harmful.
(ii) Loss of water from the surface of the leaves, is on a large scale, may result in wilting, desiccation and often lead to death of a plant in case of drought conditions.
(iii)The water stress may result in reduced growth rate and reduction in growth.
Related Topics
Privacy Policy, Terms and Conditions, DMCA Policy and Compliant
Copyright © 2018-2023 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.