Description : In single celled organisms diffusion is sufficient to meet all their requirements of food, exchange of gases or removal of wastes but it is not in case of multicellular organisms. Explain the reason for this difference. -Biology
Last Answer : Unicellular organisms can absorb sufficient oxygen because of its complete contact with the atmosphere, but in multicellular organisms the rate of absorption and diffusion becomes very less because all ... of oxygen to sustain life processes which cannot be fulfilled by the process of diffusion.
Description : The respiratory membranes facilitates the exchange of respiratory gases through diffusion . Oxygen enters the deoxygenated blood through diffusion bec
Last Answer : The respiratory membranes facilitates the exchange of respiratory gases through diffusion . Oxygen enters the ... it 40mm Hg and 46 mm Hg respectively
Description : The Correct Statements with reference to single called organisms are (i) Complex substances are not broken down in to simpler substances. (ii) Simple diffusion is sufficient to meet the requirement of exchange of gases. (iii) Specialized ... b) (ii) and (iii) (c) (ii) and (iv) (d) (i) and (iv)
Last Answer : Answer: (c)
Description : The exchange of gases in the alveoli of the lungs takes place by (a) passive transport (b) active transport (c) osmosis (d) simple diffusion.
Last Answer : d) simple diffusion.
Description : Beings from four phyla of the animal kingdom “breath” (do gas exchange) by diffusion. Which are those phyla? How is this type of respiration associated to features present in those animals?
Last Answer : The phyla of the animal kingdom whose beings do gas exchange by diffusion are the poriferans, the cnidarians, the platyelminthes (flatworms) and the nematodes (roundworms). This type of respiration in these beings is possible because their tissues and cells are relatively close to the exterior.
Description : Pick out the correct statement. (A) Higher hold up of the solid in the rotary dryer results in better exposure of the solids to the gas (B) The 'Hatta number' is ... reflux in case of distillation operation requires infinite number of plates for a binary system separation
Last Answer : (C) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is linear in the case of steady state equimolal counter-diffusion
Description : The movement of glucose into a cell occurs by a. Facilitated diffusion. b. Active transport. c. Simple diffusion. d. Phospholipid exchange.
Last Answer : b. Active transport.
Description : (a) “The breathing cycle is rhythmic whereas exchange of gases is a continuous process”. Justify this statement. (b) What happens if conducting tubes of circulatory system develops a leak? State in brief, how could this be avoided? (c) How opening and closing of stomata takes place? -Biology
Last Answer : (a) The breathing cycle involves inhalation and exhalation of air due to alternate expansion and contraction of thoracic cavity. Thus it is a rhythmic process. But exchange of gases is a continuous process ... pore opens up. When water moves out the guard cells shrinks and the stomatal pore closes.
Description : By which of the following can movement of materials across animal cell membranes be accomplished? I Active transport, II Diffusion, III Pinocytosis (A) I only (B) II only (C) I and II only (D) All I, II, and III
Last Answer : Will be only two.
Description : Which of the following factor can affect the rate of diffusion of gases `?`
Last Answer : Which of the following factor can affect the rate of diffusion of gases `?` A. Thickness of the ... . Pressure of the gases D. All fo the these
Description : Normal diffusion capacity of gases in human lungs in order is :-
Last Answer : Normal diffusion capacity of gases in human lungs in order is :- A. `O_(2) gt N_(2) gt CO_(2)` B. `CO_(2) gt ... CO_(2)` D. `O_(2) gt CO_(2) gt N_(2)`
Description : When does diffusion of gases takes place?
Last Answer : Diffusion of gases takes place when the gases do not react with one another.
Description : Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial ... at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1
Last Answer : (C) Azeotropes obey Raoult's law at all temperature
Description : The value of NA/(NA + NB), for steady state equimolal counter diffusion of two gases 'A' and 'B' is (A) 1 (B) ∞ (C) 0.5
Last Answer : (B) ∞
Description : The relation among various mass transfer co-efficients (M.T.C) for ideal gases is given by (where, Kc & Km are M.T.C. for equimolar counter diffusion with concentration & mole fraction respectively as the driving ... (C) Kc = Kp . RT = Km . RT/p (D) None of these
Last Answer : (C) Kc = Kp . RT = Km . RT/p
Description : Explain diffusion & its law. Also explain diffusion in gases & liquids.
Last Answer : Ans : Diffusion : The spreading of a substance through medium like air or liquid is called diffusion. The rate of diffusion of a substance depends upon its molar mass or density. Example : When ... the available space due to their kinetic energy. This spreading of gas is called diffusion in gas.
Description : Which of the following vacuum pumps operates by using a very cold surface to trap the gases on the cold surface? Is it a: w) sublimation pump x) turbo pump y) cryopump z) diffusion pump.
Last Answer : ANSWER: Y -- CRYOPUMP
Description : (a)Explain how does the exchange of gases occur in plants across the surface of stems, roots and leaves. (b) How are water and minerals transported in plants ? -Biology
Last Answer : a) In plants there are tiny pores called stomata on leaves and lenticels in stem which facilitate the exchange of gases. Carbon dioxide is taken in and oxygen given out {during photosynthesis} and vice ... within the plant, to all parts like the stem, roots, fruits etc. in all directions.
Description : Given statement is true or false Statement: Actual site of diffusion of `O_(2) and CO_(2)` between blood and atmospheric air is exchange part.
Last Answer : Given statement is true or false Statement: Actual site of diffusion of `O_(2) and CO_(2)` between blood and atmospheric air is exchange part.
Description : Assertion : - Blood in cockroach is colourless with no respiratory pigment. Reason : - Gasesous exchange occurs through diffusion in haemolymph.
Last Answer : Assertion : - Blood in cockroach is colourless with no respiratory pigment. Reason : - Gasesous exchange occurs through ... A. A B. B C. C D. D
Description : Thyroid gland takes up circulating iodine (A) By simple diffusion (B) By facilitated diffusion (C) By active uptake (D) In exchange for chloride
Last Answer : Answer : C
Description : The exchange of material takes place (A) Only by diffusion (B) Only by active transport (C) Only by pinocytosis (D) All of these
Last Answer : D
Description : Which of the following statement(s) is/are true concerning the pathophysiology of gas exchange? a. Hypoventilation in relation to perfusion can result in an oxygen saturation of less than 100% ... does not occur under normal circumstances d. The normal arterial oxygen saturation should be 100%
Last Answer : Answer: a, b Under normal conditions, red blood cells in the pulmonary capillaries become fully saturated and oxygen dissolves in plasma resulting in blood PO2 of 100 and O2 saturation of 100%. This ... the fact that normal arterial PO2 is 90-100 mm Hg and the normal O2 saturation is 98%
Description : In arthropods why isn't gas exchange done through cutaneous diffusion?
Last Answer : In arthropods the impermeability of the exoskeleton makes the passage of gases difficult. In addition the new methods of respiration present in arthropods were preserved by evolution because they were more efficient for those animals.
Last Answer : (D) All of these
Description : Exchange of oxygen, carbon dioxide, nutrients and waste products from mother to fetus occurs through diffusion across the: a) chorionic villi (pron: core-e-on-ick villi) b) endometrium c) corpus luteum d) colostrum
Last Answer : ANSWER: A -- CHORIONIC VILLI
Description : How are the alveoli designed to maximise the exchange of gases ? -Biology
Last Answer : (i) The alveoli are thin walled and richly supplied with a network of blood vessels to facilitate exchange of gases between blood and the air filled in alveoli. (ii) Alveoli have balloon-like structure. Hence, provide maximum surface for exchange of gases.
Description : How are the lungs designed in human beings to maximise the area for exchange of gases ? -Biology
Last Answer : Within the lungs, the air passage divides into smaller and smaller tubes, called bronchi which in turn form bronchioles. The bronchioles terminate in balloon-like structures, called alveoli. The ... vary thin walls and contain an extensive network of blood vessels to facilitate exchange of gases.
Description : A Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment. : -Biology
Last Answer : In unicellular organisms the entire body of the organism is in contact with the environment hence exchange of materials can take place but, in multicellular organisms the entire body of the organism is not in contact with the environment and hence simple diffusion is not helpful.
Description : How are the alveoli designed to maximise the exchange of gases? -Biology
Last Answer : Alveoli are small pouches or sacs like structure. They are surrounded by blood capillaries. Thus a large amount of air is brought in contact with the air in the lungs. More than millions of ... area for the exchange of gases. The availability of large surface area maximises the exchange of gases.
Description : (a) Draw a diagram of human respiratory system and label the following: (i) part where air is filtered by fine hair and mucus (ii) part which terminates in balloon - like structures (iii) ... (b) Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms? -Biology
Last Answer : (a) (b) Quantity of dissolved oxygen is fairly low in water as compared to the amount of oxygen in air. Aquatic organisms therefore have to breath faster than terrestrial organisms to absorb the required amount of oxygen from the water.
Description : The primary site of exchange of gases in our body? -Biology
Last Answer : answer:
Description : The most important chemical process in digestion is: a) diffusion b) active transport c) hydrolysis
Last Answer : ANSWER: C -- HYDROLYSIS
Description : Water vapour comes out from the plant leaf through the stomatal opening. Through the same stomatal opening carbon dioxide diffuses into the plant during photosynthesis. Reason out the above ... Both processes can happen together because the diffusion coefficient of water and CO2 is different
Last Answer : (d) Both processes can happen together because the diffusion coefficient of water and CO2 is different
Description : The process by which cell can take in fluid and molecules too large to be carried across the plasma membrane by active transport is called a. phagocytosis b. Pinocytosis c. absorption d. diffusion
Last Answer : Pinocytosis
Description : The process of taking dissolved material into the substance of the cell is called. a. Phagocytosis b. Pinocytosis c. absorption d. diffusion
Last Answer : absorption
Description : The figure given below shows a small part of human lung where exchange of gases takes place. In which one of the options given below, the one part, A,
Last Answer : The figure given below shows a small part of human lung where exchange of gases takes place. In which ... red blood cell-transport of `CO_(2)` mainly
Description : How are gases exchange in a sponge?
Last Answer : they are not
Description : What are opening in the bark that allows the exchange of gases?
Last Answer : What is the answer ?
Description : The exchange of gases in mammals takes place in the (a) larynx (b) trachea (c) alveoli (d) bronchi
Last Answer : Ans:(c)
Description : What is the part of the vascular system that performs exchange of gases and other substances with the tissues?
Last Answer : Only capillaries perform exchange of gases and other substances with the tissues.
Description : The exchange of gases takes place in the leaves through these pores for the purpose of photosynthesis. These pores are called – (1) Guard Cells (2) Stomata (3) Chloroplast (4) None of the above
Last Answer : (2) Stomata Explanation: Stomata are tiny pores present on the surface of the leaves via which exchange of gases takes place in the leaves for the purpose of photosynthesis. However, exchange of gases also occurs across the surface of stems, roots and leaves as well.
Description : Explain the exchange of gases in lungs?
Last Answer : At the lungs exchange of carbon dioxide and oxygen takes place in alveoli. This process takes place by the process of diffusion. In lungs pressure of carbon dioxide is greater than pressure of carbon ... The oxygen first diffuses in fluid present in the walls of alveoli and then into the blood.
Description : How exchange of gases takes place in terrestrial animals?
Last Answer : Through Trachea: - Insects and other land arthropods use tracheal tubes for exchange of gases. This is very simple and effective method. These animals have network of tracheal tubes. These tubes on ... In them the respiratory system consists of alveoli. Birds have air sacs in addition to lungs.
Description : Write a note on exchange of gases in aquatic animals?
Last Answer : Through Skin: - The skin of aquatic animals is moist and rich with blood so that oxygen can diffuse directly. Frog and tortoises breathe through skin during hibernation. Through Gills: - Gills are ... have external gills. Water enters through mouth flows over the gills and goes out of the body.
Description : The figure given below shows a small part of human lung where exchange of gases takes place. Select the option which represents labelled part (A, B, C or D) correctly identified along with its function. ... Exchange of O2 and CO2 takes place here (d) B : Red blood cells - Transport of CO2 mainly
Last Answer : (b) A : Alveolar cavity - Main site of exchange of respiratory gases
Description : The figure shows a diagrammatic view of human respiratory system with labels A, B, C and D. Select the option which gives correct identification and main function and / or characteristic. (a) C - ... air. (d) B - Pleural membrane - Surround ribs on both sides to provide cushion against rubbing.
Last Answer : (a) C - Alveoli - Thin walled vascular bag like structures for exchange of gases.
Description : 6. Liquefaction of gases cannot be done by (A) Exchange of heat with colder stream (B) Adiabatic expansion through a throttle valve (Joule-Thomson expansion) (C) Merely compressing it beyond critical pressure (D) Adiabatic expansion against a piston or in a turbine
Last Answer : (C) Merely compressing it beyond critical pressure