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Question: 1
Define excretophore./what are excretophores %why?
Answer: 1
Leaves are called excretophore because they collect nitrogenous waste from different plant parts and they store temporarily, at autumn season plants shed their leaves and wastes are removed from plant body.
Question: 2
Differentiate between hypotonic and hypertonic solution.
Answer: 2
Hypotonic Solution: Dilutes solution compared to the cell concentration is called hypotonic solution.
Question: 3
Define anhydrobiosis with an example.
Answer: 3
The ability to tolerate dehydration, this process is called anhydrobiosis.For example: Kangaroo Rat a desert animal can tolerate dehydration without drinking water by feeding desert plants containing more carbohydrates, which produce water of metabolism.
Question: 4
What are Xerophytes?Give its examples.
Answer: 4
Plant which grow under drought or in extreme shortage of water theses plants are called xerophytes. E.g, Cacti, Opuntia, Calatropis.
Question: 5
Define Homeostasis.
Answer: 5
The protection of internal environment from the harms of fluctuation in external environment is called homeostasis.The homeostasis keeps the internal fluctuation in a narrow range with various control systems compared to wider external fluctuation. The control system would not let the body flooded with water in abundant supply of water.
Question: 6
Define Excretion.
Answer: 6
Removal of waste products (especially nitrogenous wastes) from the body is called excretion.
Question: 7
Differentiate between hydrophytes and mesophytes.
Answer: 7
Hydrophytes: Hydrophytes are the plant which grow in aquatic environment (abundant water),they have large leave surface area and stomata are present on the upper side of leaves, they have high rate of transpiration. E.g., Water lilli, Wolfia, Pistia etc.
Question: 8
Write four osmoregulatory adaptations in xerophytes.
Answer: 8
They have following adaptations:
  1. Sunken stomata
  2. Thick cuticle
  3. Water storing tissues
  4. Reduced or complete absence of leaves.
Question: 9
What is hypertonic environment and what changes occur in a cell in such environment?
Answer: 9
The more concentrated external environment is called hypertonic environment. The hypertonic environment makes the cell solution concentrated and cell shrinks due loss of water.
Question: 10
Differentiate between osmoregulation and thermoregulation.
Answer: 10
Osmoregulation: The mechanism of regulation, generally between organism and its environment of solute and the gain & loss of water is called osmoregulation.
Question: 11
Give four adaptation of xerophytes.
Answer: 11
Xerophytes have following adaptations.
  1. Reduced leaves
  2. Hidden stomata
  3. Thick cuticle
  4. Water storing tissues
Question: 12
Give the role of contractile vacuole.
Answer: 12
Contractile vacuole play an important tole in osmoregulation in aquatic animals, it absorbs extra water from the cell and excerta it out.For example in paramecium two contractile vacuoles are present, which perform osmoregulatory function.
Question: 13
What are heat-shock proteins?
Answer: 13
Most plants have adopted to survive in heat stress as the plants of temperate regions face the stress of 40°C and above temperature.The cells of these plants synthesize large quantities of special proteins called heat shock proteins.These proteins embrace enzymes and other proteins thus help to prevent denaturation.
Question: 14
What are effects of ADH and Aldosterone on work of nephron?
Answer: 14
Aldosterone and ADH help in full conservation of water in proximal convoluted part of the nephron and concerned with maintenance of urine concentration
Question: 15
Why leaves are said to be excretophore?
Answer: 15
The falling of yellow leaves in autumn is the seasonal time for the plants to get rid of the accumulated wastes and because of this reason leaves are said to be excretophore.
Question: 16
What are heterotherms?Give example.
Answer: 16
These are the animals that are capable of varying degrees of endothermic heat production but generally do not regulate their body temperature within a narrow range.For example bats and humming birds.
Question: 17
What is hypercalcemia? Give its effects.
Answer: 17
High level of circulating calcium in the blood is called hypercalcemia.
Hypercalcemia may cause kidney stone.
Question: 18
Name two hormones involved in nephron.
Answer: 18
Anti diuretic hormone and Aldosterone are involved in nephron function.
Question: 19
Give adaptation of marine fish for its survival in cold environment.
Answer: 19
These fishes have a thick layer of insulting fat called blubber, which prevent excess heat loss from the body.
Question: 20
Write structural adaptation for regulation of heat exchange between animals and environment.
Answer: 20
Structural adaptation in the animals for exchange of heat are sub-dermal fatty layer insulation called pelage, the presence of sweat glands and lungs modified fro painting.
Question: 21
Define dialysis.Give its types.
Answer: 21
When the kidneys of a patient are failed then nitrogenous wastes are removed by filtering blood through dialysis.Dialyzing machine is called artificial kidney machine.
It has two types:
  1. Peritoneal dialysis
  2. Hemodialysis
Question: 22
Give two adaptation of plants to high temperature condition.
Answer: 22
Plants have following adaptations for surviving high temperature.
  1. Plant synthesizes heat shock proteins and
  2. Plants use evaporative cooling to manage with high temperature.
Question: 23
Define the process of painting with one example.
Answer: 23
It is structural adaptation for heat regulation in dogs.Panting is evaporative cooling in the respiratory tract for temperature regulation.
Question: 24
Differentiate between ureotelic and uricotelic animals.
Answer: 24
Ureotelic Animals: Animals which excrete urea are called ureotelic e.g sharks.
Question: 25
Write two types of synthesis functions of liver and effects on homeostasis.
Answer: 25
Synthesis function of liver include.
  1. Synthesis of urea, ammonia and uric acid. It assists kidney for the removal of wastes.
  2. Synthesis of plasma proteins like proteins like prothrombin and fibrinogen. it maintains osmotic balance of blood and help in blood clotting.
Question: 26
Illustrate the function of Malpighian Tubules.
Answer: 26
Malpighian tubules extracted waste products from the haemolymph of insects and they pour it into digestive tract, where they are converted into nitrogenous wastes
Question: 27
What is flame cell Why it is called so?
Answer: 27
Flame cell is the part of excretory system of planaria.It is called flame cell because it has tuft of cilia, which looks like flickering flame of candle.
Question: 28
Why ammonia is more toxic than other nitrogenous wastes?
Answer: 28
Ammonia is very toxic and dissolve quickly in body fluids,Thus it must be kept in low concentration in the body.To maintain low concentration below that of body requires, large volume of water is used to eliminate it as urine.
Question: 29
Name waste products produced during metabolism of purine and pyrimidine.
Answer: 29
Waste products of purine and pyrimidine are hypoxanthine, xanthine, uric acid, allantoin, urea and ammonia.
Question: 30
What is counter-current multiplier.
Answer: 30
This mechanism causes gradual osmotic out flow from the filtrate back to kidneys as it passes downward in the descending loop of Henle.Furthermore, ascending loop of henle does not allow out flow of water from its filtrate,instead actively transport sodium ions into kidney interstitium to sustain its high concentration.
Question: 31
Described the structure of a flame cell.
Answer: 31
It is a complete eukaryotic cell.It has a unucles, other cell organelles and a cavity where the waste products are collected.Each flame cell has a tuft of cilia, whose beating propel interstitial fluid into the tubular system
Question: 32
What are different metabolic wastes in humans?
Answer: 32
Following are the metabolic wastes.
  1. Urea
  2. Uric acid
  3. Bilirubin
  4. Creatinine
  5. Xanthine
  6. Hypoxanthine
Question: 33
What are juxtamedullary nephrons?
Answer: 33
Nephrons are arranged along the border of cortex so that their tubular system looping deep in inner medulla are called juxtamedullary nephrons.These juxtamedullary nephrons are specifically involved in the production of concentrated urine.
Question: 34
What is metanephridium?
Answer: 34
It is the excretory organ of earthworm and other annelids.In each segment of the body metanephridium is present which individually collects the wastes and then remove them.
Question: 35
Explain briefly glomerular filtrate.
Answer: 35
It is the filtrate which is produced by the filtration of blood from the glomerulus,it contains glucose,amino acid,small blood cells,salts,nitrogenous wastes and water.
Question: 36
What is renal failure?
Answer: 36
When kidneys perform no more function and cannot filter blood to produce nitrogenous waste, this is called renal failure or uemia.
Question: 37
What is hemodialysis and peritoneal dialysis?
Answer: 37
Hemodialysis: mean cleaning of blood. In it blood is circulates through a machine which contains a dialyzer. Dialyzer has two spaces separated by thin membrane. Blood passes through one side of membrane and dialysis fluid from other side. The waste and excess water pass from the blood through the membrane into the dialysing fluid.
Question: 38
What is vasa recta?
Answer: 38
In juxtamedullary nephrons additional capillaries extend down to from a loop of vessels called vasa reata.
Question: 39
What is lithotripsy?
Answer: 39
(Litho means stone, tripsy means breakdown) It is the technique used to break up stones that form in the kidney, ureter or gall bladder.It is used for non- surgical removal of kidney stones.
Question: 40
Write a short note on kidney transplantation.
Answer: 40
Dialysis is used temporerily.In high degree renal failure also called uremia or end stage renal disease.The dialysis is replaced by surgical transplantation of kidney of a matching donor kidney is the only option left as the permanent treatment. Kidney Should be of nearest to avoid tissue rejection.
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Jun 11, 2020

An question poucha h ka define osmoregulation and thermoregulations pahly page par tu osmoregulation ke define lihke hoi h thermoregulation ke kasy nikly gy is ko kis tarha sy click karna h

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Jun 11, 2020

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Umme Habiba Sir g pak study kay questions chaihiyah mujhay
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Jun 11, 2020

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