CBSE Class 10 Science Biology Transport Enrichment Assignment

Question. In which of the following are the largest amounts of nitrogen excreted from a mammalian body ?
(a) breath
(b) sweat
(c) urine
(d) faeces

Answer : C

Question. Which one of the following has cytoplasm but no nucleus :
(a) xylem vessel
(b) sieve tube
(c) tracheid
(d) companion cell

Answer : B

Question. The process of carrying food from the leaves to other parts of a plant is called :
(a) transpiration
(b) transportation
(c) translocation
(d) transformation

Answer : C

Question. Which of the following is the only conducting tissue in non-flowering plants ?
(a) xylem vessels
(b) sieve tubes
(c) companion cells
(d) tracheids

Answer : D

Question. Which of the following helps in the upward movement of water and dissolved minerals from the roots to
the leaves through the stem ?
(a) transportation
(b) translocation
(c) tropic movement
(d) transpiration

Answer : D

Question. Which one of the following does not have valves ?
(a) heart
(b) arteries
(c) capillaries
(d) veins

Answer : C

Question. Which of the following is accomplished in a plant by utilising the energy stored in ATP ?
(a) transport of food
(b) transport of water and minerals
(c) transport of oxygen
(d) transport of water, minerals and food

Answer : A

Question. Coagulation of blood in a cut or wound is brought about by :
(a) plasma
(b) platelets
(c) WBC
(d) RBC

Answer : B

Question. The blood vessel which carries oxygenated blood from the lungs to the heart is :
(a) main artery
(b) pulmonary artery
(c) main vein
(d) pulmonary vein

Answer : D

Question. The instrument for measuring blood pressure is called :
(a) manometer
(b) sphygmomanometer
(c) barometer
(d) potentiometer

Answer : B

Question. The excretory unit in the human excretory system is called :
(a) nephron
(b) neuron
(c) nephridia
(d) kidneyon

Answer : A

Question. The substance which is not reabsorbed into the blood capillaries surrounding the tubule of a nephron is mainly :
(a) glucose
(b) amino acid
(c) urea
(d) water

Answer : C

Question. The procedure of cleaning the blood of a person by using a kidney machine is known as :
(a) ketolysis
(b) hydrolysis
(c) dialysis
(d) photolysis

Answer : C

Question. The excretory organs in an earthworm are :
(a) nephridia
(b) nephrons
(c) raphides
(d) ureters

Answer : A

Question. The cells in our blood which destroy disease-causing germs, are :
(a) platelets
(b) skin cells
(c) RBCs
(d) WBCs

Answer : D

Question. The wave of expansion of an artery when blood is forced into it is called :
(a) flow
(b) heart beat
(c) pulse
(d) ticking

Answer : C

Question. In autotrophs, water is transported through :
(a) root hair
(b) phloem
(c) stomata
(d) xylem

Answer : D

Question. An animal having double circulation in a three-chambered heart is :
(a) fish
(b) snake
(c) deer
(d) sparrow

Answer : B

Question. (a) What is lymphatic system ? What are its functions ?
(b) What is blood pressure ? What are the two factors used to express the blood pressure of a person ?
(c) Name the main nitrogenous waste in the human blood. How is it removed from the blood ?
Answer : (a) Lymphatic system: A system of tiny tubes called lymph vessels (lymphatics) and lymph nodes (lymph glands) in the human body which transports the liquid called lymph from the body tissues to the blood circulatory system is called lymphatic system.
Functions of the lymphatic system:
(i) It takes part in the nutritive process of the body.
(ii) It protects the body by killing the germs drained out of the body tissues with the help of lymphocytes contained in the lymph nodes, by making antibodies.
(iii) It helps in removing the waste products like fragments of dead cells etc.
(b) Blood pressure: The pressure at which the blood is pumped around the body by the heart is called blood pressure. The two factors which express the blood pressure of a person are a systolic pressure and diastolic pressure.
(c) Urea is the main nitrogenous waste in human blood. It is removed from the body in the form of urine through the kidneys.

Question. (a) Name the various organs of the human excretory system.
(b) Draw a neat labelled diagram of the human excretory system.
(c) What is the function of excretory system in humans ?
Answer :  (a) The excretory system of human beings consists of the following main organs: two kidneys, two ureters, bladder, and urethra.
(b)
(c) The excretory system removes the poisonous waste substances from the body in the form of urine and maintains ionic balance called osmoregulation.

Question. (a) Describe the mechanism of urine formation in human excretory system. Draw a labelled diagram to illustrate your answer.
(b) Where is urine carried through ureters ?
(c) What is urethra ?
Answer :  (a) Mechanism of Urine Formation\
When proteins are digested, amino acids are formed. The metabolism of amino acids in the body leads to the formation of ammonia. Ammonia is combined with carbon dioxide to from urea which is the principal from of nitrogenous waste in mammals. The formation of urea takes place in the liver and is carried by the blood to the kidneys where the nephric tubules filter the urea from the blood and eliminate it along with some water and certain other substance in the form of urine.

Urine begins as a simple filtrate of the blood. However, the composition of the initial filtrate in the nephron and that of the urine shows marked differences. The total urine volume from the beginning to the end of the systems also shows dramatic changes. In a person weighing 70 kilograms, an average of 180 liters of fluid is filtered from blood each day. However, only about one to two liters of urine is actually excreted per day. Approximately, 99 percent of the water filtered is reabsorbed back to the bloodstream.

All these changes are the result of tubular reabsorption and secretion by the different regions of the nephron. It takes the blood filtrate from the glomerulus and reabsorbs and secretes substances into and from the glomerular filtrate to make it the final urine which is excreted away. The formation of urine involves three processes: (a) glomerular filtration, (b) tubular absorption, and (c) tubular secretion.

Glomerular Filtration
The first step in the formation of urine is the filtration of blood. The blood in the glomerulus is separated from the cavity within the Bowman's capsule only by (i) a thin layer of tissue composed of the single-celled endothelial lining, (ii) a layer of material called the basement membrane, and (iii) the single-celled lining of the Bowman's capsule. This barrier permits the filtration of the fluid from the capillaries into the Bowman's capsule. The energy for filtration is derived from the hydrostatic pressure of the blood. The composition of the ultrafiltrate in the Bowman's capsule is the same as the composition of blood, except that it does not contain blood cells and proteins. The appearance of red blood cells and protein in the urine indicates a defect in the process of glomerular filtration.
(b) The urine is carried to the urinary bladder through the ureters.
(c) The urethra is the passageway between the bladder and the external part of the body, which allows urine to be excreted from the body.

Question. (a) What is meant by dialysis ? What type of patients are put on dialysis ?
(b) Explain the principle of dialysis with the help of a labelled diagram.
Answer :  (a) Dialysis is a treatment or process that filters and purifies the blood using a machine. Patients suffering from kidney failure are put on dialysis.
(b) Principal of dialysis : The procedure of Dialysis is based on the principle of diffusion and ultrafiltration of fluid across a semipermeable membrane. 

Question. (a) Why is transport of materials necessary in an organism (plant or animal) ?
(b) What is the need of special tissues or organs for transport of substances in plants and animals ?
(c) How are water and minerals transported in plants ?
(d) How is food transported in plants ?
Answer :  (a) Transport of materials is necessary for plants and animals so as to maintain a regular supply of oxygen and nutrients to all the cells present in the body.
(b) Organisms like plants and animals need special tissues and organs for the transport of substances so that they can easily transport essential substances like food, oxygen, and water from one part of the body to another in a multicellular organism.
(c) Water and minerals are absorbed by the cells of the root hair. As water is absorbed by the root hairs from the soil, it is transported to various parts of the plants through the xylem tubes by the cohesion of water molecules to each other.

1. State two structural difference between an artery and vein

Name the non nucleated cells present in human blood and state one function of the cells Draw a labeled diagram of the heart

2. Why is circulation of blood in man known as double circulation?

Which blood cell in human blood carries haemoglobin? What is its average life span? Draw a labeled diagram of human heart 

3. Mention the substances which are transported through the phloem to various parts of the plant also mention the organs in which these substances are synthesized