Chp-6 Life processes

Question 1

How do we distinguish between living things and An non living thing

Answer 1

On the basis of reproduction, growth, senses, respiration, movement, consumption, stimuli, evaluation and homoeostasis

Question 2

Define homoeostasis

Answer 2

The definition of homeostasis is the ability or tendency to maintain internal stability in an organism to compensate for environmental changes.

Question 3

Why is molecular movements needed for life

Answer 3

Living organisms have well organised structures; we can have tissues, tissues can have some, and cells have smaller components. Because of the effects of the environment, this organised, order nature of living structure is likely to keep breaking down over time. If order breaks down, the, organism will no longer be alive. So living creatures must keep repairing and maintaining their structures. Since all the structures are made up of molecules, they must move molecules around all the time.

Question 4

Explain Parasitic nutrition

Answer 4

The parasitic nutrition is that nutrition in which an organism derives its food from the body of another living organism called host without killing it.
_ Parasite: an organism which feeds on another living organism
_Host: the organism from whose body food is obtained by a parasite
_Parasite receives its food from the host but gives no benefit to the host in return. Parasite usually has the host. The host will be a plant or animal.
_Parasitic mode of nutrition is a observed in several fungi, bacteria, a few plans like cuscuta and mistletoe and some animals like Plasmodium, round warm, ticks , leeches, lice, etc
_ Most of the diseases which affect mankind domestic animals and his crops a cost of parasites.
_ The micro organism plasmodium causes. Malaria and round warm live inside the body of man and domestic animals

Question 5

Define life processes and all the important life processes

Answer 5

The processes which together perform job of maintenance and repairing and prevent damage and Break down of body and its function, using the energy are called life processes.

Nutrition is the process of transfer of source of energy from outside the organisms body to inside. It is the process that involves intaking of food and utilising it for various metabolic activities

Transportation is the process in which food is transported to Every cell of the body through blood by the circulatory system

The process of acquiring oxygen from outside body, and using it in the process of breakdown of food sources for the cellular means, is called respiration. In this oxidation of food takes place inside every cell of the body

The process in which the waste products are removed from the body and discarded outside is called excretion

Question 6

How is life on the earth depend on carbon-based molecules

Answer 6

Food is made up of carbon-based molecules such as carbohydrates fats and proteins. Carbohydrates and fats provide energy while proteins are required for bodybuilding, repair and maintenance

Question 7

Why do single felled organism not require specific organs for taking in the food, or exchange of the gases

Answer 7

In unicellular organisms like amoeba, all the life processes take place through the entire surface of the cell because the entire surface is in the contact with the environment and life process can take place by simple diffusion while in multi cellular organisms all the cells man not been the direct contact with the surrounding medium And so the required specific organs.

Question 8

What is the branch of Biology that deals with the study of life processes are vital activities

Answer 8

Physiology

Question 9

Why is molecular movement absent in virus when it is outside the host cell

Answer 9

When outside the living cells, virus is behave as a nonliving do not show any molecular movement. But when it enters inside a living cell It takes over the metabolic machinery of the host cell for the synthesis of proteins, multiplication of genetic material that had all the information, necessary to produce new viruses

Question 10

Define nutrients

Answer 10

Nutrients Are organic or in organic materials which organism Obtains from its surrounding and use it it as a source of energy or for biosynthesis of its body constituents like tissues and organs

Question 11

What are enzymes and hormones

Answer 11

Enzymes are biocatalyst Which break down complex Organic compounds into simpler ones. The release through Exocrine gland

Hormones are chemical messengers that she leaves messages directly into bloodstream through endocrine gland

Question 12

Define autotrophic nutrition, autotrophs heterotrophs and heterotrophic nutrition

Answer 12

It is the process by which organisms takein simple inorganic substances lik CO2 and H2O and use them to synthesise organic molecules and then convert them into stored forms of energy.

• For eg Corn is a food because corn cob has been made by corn plants by process of photosynthesis (extra starch)
• Organism which can make their own food from inorganic substances present in the environment called autotrophs(producers) , For eg green plants and autotrophic bacteria.

_Heteros - other and trophe- nutrition
_The mode of nutrition in which organisms Cannot synthesise its own food from simple in organic materials and THUSderive the nutrition by taking ready-made food, from other dead plants and animal is heterotrophic. (Consumers)
-The organisms which cannot make their own food from simple in organic substances like carbon dioxide and water and depend on other other organism for food are called heterotrophs. For example yeast.

Question 13

Define photosynthesis

Answer 13

Photosynthesis is the process of preparing organic food, carbohydrates, by combining carbon dioxide and water using solar energy by chlorophyll pigments

Question 14

Describe holozoic mode of nutrition

Answer 14

Holozoic nutrition means feeding on solid food. The holozoic nutrition is that nutrition in which an organism takes the complex organic food material into its body by the process of ingestion, the ingested food is digested into simpler substances and then absorbed into the blood cells of the organism. The undigested and unabsorbed the part of the food is thrown out by egestion
For eg- Venus fly trap and pitcher plant

Question 15

Where does the first true and the oxygenic photosynthesis start

Answer 15

Cyanobacteria (blue green algae). 90% of the total photosynthesis is carried out by hydrophytes ; mostly marine algae

Question 16

What are the requirements for photosynthesis

Answer 16

Sunlight, photosynthetic pigment, carbon dioxide, water

Question 17

Why is leaf first boiled in hot water n then dip in warm be denatured spirit

Answer 17

boiled- to kill, and to break the cell membranes of leaf cells and make the leadf more permeable to iodine soln, so that it reach the starch present inside the leaf cells.
Denatured spirit-Remove chloro Phil that interferes in the test for starch it with green colour

Question 18

Explain saprophytic mode of nutrition

Answer 18

_Saprophytic nutrition is that nutrition in which an organism obtains its food from decaying organic matter of dead plants, dead animals and rotten bread, etc.
_Sapro means rotten, so saprophytes are the organisms which obtain their food from dead plants, dead and decaying animal bodies and other decaying organic matters.
_Fungi like bread mould, mushrooms, yea teaAnd many bacteria as a call saprophytes.
_ Saprophytes break down the complex organic material present in dead and decaying matter and convert them into simpler substances outside the body and then absorbed the simpler substances

Question 19

True or false- Photosynthetic pigments absorb all the lights.

Answer 19

Falls; photosynthetic pigments absorb only white light from electromagnetic spectrum which consist of Vibgyor

Question 20

What are variegated leaves

Answer 20

The leaves containing both green and non-green parts. For example croton or money plant

Question 21

Why is potassium hydroxide used during the experiment of demonstration that carbon dioxide is necessary for photosynthesis

Answer 21

It is because potassium hydroxide is used to absorb carbon dioxide

Question 22

True or false

Desert plants take up carbon dioxide at night

Answer 22

True; desert plants take up carbon dioxide at night and prepare an intermediate which is acted upon by the energy absorbed by the chlorophyll during the day and forms glucose

Question 23

How do aquatic plants obtain carbon dioxide

Answer 23

An aquatic plants, carbon dioxide is obtained from the water where it remains present in the dissolved form. Such plants absorb carbon dioxide in the dissolved form to diffusion, all over the surface from the surrounding water

Question 24

What are stomata and what are it’s functions

Answer 24

Stomata is a tiny pores or microscopic aperture On the surface of leaves Guarded by two kidney shaped or bean shaped shaped guard cells
Massive amount of gas exchange takes place in leaves through stomata. Exchange of gases also occurs across the surface of stem and roots. Transpiration also takes place through stomata.

Question 25

How is the distribution of stomata in broad leaved plants different from narrow leaved plants?

Answer 25

.In most broad leaf plants stomata is only in the lower surface of the leaf but in narrow leaved plants, the plants the stomatas are equally distributed on both the sides of the leaf

Question 26

What are guard cells

Answer 26

They are kidney shaped cells which cover single stroma and also contain chloroplast

Question 27

True or false- In all plants, Stomata are open during daytime and close during the night time

Answer 27

Falls in desert plants stomata are open in night time to check excessive loss of water.

Question 28

How does stomata open or close

Answer 28

When The guard cells swell and become turgid due to the entry of water stomata opens . But when the guard cells shrink due to loss of water the stomata close

Question 29

How is water taken in by plants

Answer 29

Water is absorbed by plants from the soil through the process of osmosis. Some mineral salts like nitrogen, phosphorus, iron and, magnesium are also transported to different parts of the plant along with the water

Question 30

True or false

In The chloroplast of the leaves the water molecules into hydrogen and oxygen with the help of light energy of sun

Answer 30

True

Question 31

What would happen if the green plants from earth

Answer 31

Green plants are the source of energy for all organisms. Trap the solar energy and converted into chemical energy in the form of food and give of oxygen. Then all the Herbivores will die due to starvation and so will carnivorous. Also without plants animals we have no oxygen to breathe and would die

Question 32

What element does the plant need to be able to convert glucose into proteins

Answer 32

Nitrogen is P a sensual element used in the synthesis of proteins and other compounds. Nitrogen is taken up in the form of an organic nitrates or nitrites

Question 33

Why does the less availability of water reduce the rate of photosynthesis

Answer 33

Under water deficient conditions sStomatal aperture Remains closed to reduce the loss of water by transpiration. As a consequence the entry of carbon dioxide will also be stopped . That’s why less availability of both water and carbon dioxide will reduce the rate of photosynthesis

Question 34

Explain the structure of leaf

Answer 34

In the structure of leaf we see that the middle layers in the leaf – palisade Layer and spongy layer - contain photosynthetic cells called mesophyll cells .these cells contain more chlorophyll than any other plant cells. A typical photosynthetic cell of a green leaves contain hundred or more tiny chloroplast in it, and a whole leaf may contain many thousands of photosynthetic cells. Carbon dioxide needed for photosynthesis enters from the air into the leaF Through stomata in its surface, and then defuses into Mesophyll cells and reaches the chloroplast. Water is carried to the leaf by xylem vessel and passes on to mesophyll cells by diffusion and reaches the chloroplast. There is a thin, waxy and a protective layer called cuticle above and below a leaf which helps to reduce the loss of water from the leaves

Question 35

Explain the mechanism of photosynthesis

Answer 35

1) Chlorophyll absorbs light energy
2) Conversion of light energy into chemical energy and splitting of water molecules into hydrogen and oxygen
3) H reduces CO2 and synthesises glucose whereas there is a reduction of CO2 into carbohydrates
All these events can be characterised into two main faces, light dependent phase and light independent phase

Question 36

Where does light reaction takes place

Answer 36

It takes place in thylakoids, grabs. In this chlorophyll gets activated by absorbing photons and ATP and NADPH formed. Here I Splitting of water or photolysis also takes place

Question 37

Explain the light independent reaction

Answer 37

The hydrogen which had formed as a byproduct of light reaction goes into the stroma and reacts with carbon dioxide to form CH2O. ATP and NADPH are used to perform 6 Calvin cycle which forms glucose. Fixation of carbon dioxide is catalysed by enzymes to RuBisCO

Question 38

What are the factors affecting photosynthesis

Answer 38

Light - maximum in red, violet and blue colour.

water,

temperature, - 25 Degree to 35° and the photosynthesis reduces if beyond)

carbon dioxide, (Stomata closes after 0.35%)

oxygen

Question 39

What is the necessity of converting glucose into starch and then converting the glucose into sucrose

Answer 39

Converted into starch because it is insoluble to prevent osmosis and it is converted into sucrose for transportation through phloem

Question 40

What are the adaptations of leaves

Answer 40

1) It has large surface area and large number of stomata.
2) It has a special arrangement of leaves and an extensive vein system for the transport of water
3( It has a proper concentration of chloroplast

Question 41

How does paramecium obtain its food

Answer 41

Paramecium is a tiny unicellular animal which lives in water. It uses its hair like structure s called Cilia to sweep the food particles from water and put them into its mouth. The paramecium has thin hair like structures call Cilia all over its body. When the Cilia present around the mouth region of the paramecium move back and forth, they sweep the food particles present in the water into the mouth of paramecium this is the first step in nutrition of paramecium of education and the other processes like digestion and absorption assimilation and digestion is same as in the

Question 42

True or false-

Chlorophyll pigment is a magnesium containing pigment

Answer 42

Thylakoids has chlorophyll pigment which is a magnesium containing pigment to capture sunlight, maximum and violet, blue and red colour spectrum of the VIBGYOR.

Question 43

List the difference between light reaction and dark reaction

Answer 43

Light- light required
Dark - light not required

locations- light- Grana
Dark- Strona

ATP n NADPH2- Light- Produced by conversion of light energy into chemical energy
Dark- ATP Formed during light reaction are used for fixation of carbon dioxide into carbohydrates

Sugar formation- light- no formation
Dark- sugar formation takes place

Release of oxygen - light- released
Dark - no released

Question 44

Define digestions

Answer 44

The process in which the food containing large, insoluble molecules is broken down into small, water soluble molecules which can be absorbed by the body is called digestion

Question 44

Describe the process of digestion in amoeba

Answer 44

Amoeba Is a holozoic and an omnivorous.
When it comes in contact with food particles get from pseudopodia which engulf the prey Performing a food cup. This process is called phagocytosis ingestion.
2) When it types of the encircling pseudopodia touch each other in captured into a bag called food vacuole which serves as temporary stomach secreting digestive juices
3) Absorb and fuses into cytoplasm and then get assimilated
4) Assimilation is the utilisation of digested food in various anabolic and catabolic reaction and conversion of absorbed into complex molecules for various purposes.
5) The ingestion of undigested food takes place at any point on the surface of the body

Question 44

What is mastication, bolus and chyme

Answer 44

Mastication achieving is the process in which the food is crushed and grinded by teeth.

Bolus - is the mixture of food and saliva in mouth

HYME – is the semisolid food that is expelled from stomach

Question 44

What are the three components of buckle cavity

Answer 44

Mouth into a large space known as mouth cavity or buccal cavity which accommodate muscular tongue, teeth and salivary glands
Tongue- movable muscular organ attached to the foot of the oral cavity • helps in swallowing of food, cleaning teeth, moving food in buccal cavity and helps in speaking

Teeth there are four types of teeth and I am adult human has 32 permanent teeth. •Helps in breakdown of food into smaller size and larger surface area for the enzymes to act • Helps in formation of bolus •Helps in physical digestion

Salivary glands – the secrete saliva which contain a digestive enzyme salivary amylase or ptyalin that breaks starch into maltose and dextrin.

Question 44

What is saliva and emulsification

Answer 44

Saliva is an antiseptic as it kills germs and bacteria due to the presence of enzyme called lysozyme. It makes the food soft and slippery helping in digestion of starch

Phenomena of physically breaking of large sized fat globules into large number of fat droplets by bile salt of bile juice. This increases the surface area of fats fats by lipase enzyme

Question 45

What is it oesophagus and alimentary Canal ?

Answer 45

A long tube running from mouth to the anus, which carries food through different parts of the digestive system and allows waste to exit the body. s called alimentary canal. Alimentary canal is also called Gut. It is 9 m long tube in humans.

Oesophagus r Collapsible muscular tube leading food by peristalsis from pharynx to stomach. There is no digestive gland present here but only mucus

Question 46

Explain the digestion in stomach

Answer 46

The gastric glands are present in the lining for the stomach. The food is churned in the stomach for about three hours.
Gastric juices which contain mucus, hydrochloric acid and two inactive proteolytic (protein digesting)enzymes called pepsinogen and pro-rennin. The muscular walls of the stomach helps in mixing the food to throughly with digestive juices.
HCL produces an appropriate medium of PH= 2 for the activation of Pepsinogen to pepsin and pro rennin to Rennin. It facilitates the action of enzyme pepsin and kills the bacteria present in the food.

Pepsin breaks down the proteins into peptides and proteoses

Rennin is a milk protein digesting enzyme. Mucus protects the inner lining of the stomach from the action of HCl.
Spinster muscle regulate the exit of food from stomach into the intestine due to peristaltic waves of stomach.

Question 47

What is peristalsis movement

Answer 47

Peristalsis refers to the contraction and relaxation of the muscles along the alimentary canal .This movement is involuntary and is necessary for the movement of food down the stomach and bowels down the anus.

Question 48

Explain the digestion in small intestine and aftermath

Answer 48

It is about 6.5 m long in an adult man.It is the site of complete digestion of carbohydrates proteins and fats.; Food is mixed with three digestive juices- bile juice, Pancreatic juice and intestinal juice.
Bile juice and salt from the liver provides alkaline medium and emulsifies fat.But it is a non- Enzymatic digestive juice so has no chemical action on food.

Juice from pancreas contain trypsin, pancreatic amylase and pancreatic lipase enzymes which digest proteins to peptides, starch to maltose and dextrin and emulsified fats in fatty acids And glycerol.

The walls of intestine secret intestinal juice which contains enzymes for completion of digestion of peptides into amino acid’s, maltose into glucose and fats into fatty acids and glycerol.

The inner lining of small intestine has numerous fingerlike projections called villi which increase the surface area for absorption of digested food and are supplied with blood vessels to take the absorbed food to each and every cell of the body where it is assimilated for various purposes.
Aftermath-
The blood carries Digested and dissolved food to all parts of thebody where it’s become assimilated as the parts of cell.It is assimilated food is used by body cells for obtaining energy as well as for growth and repair of the body. The energy is released by oxidation of assimilated food in the cell Touring respiration.The food which is not used by a body is immediately stored In liver the form of Carbohydrate calledglycogen

Question 49

What causes ulcer

Answer 49

And ulcer Of the stomach is called peptic ulcer Which is caused by high acidity of gastric juices secretion

Question 50

Explain dental caries

Answer 50

_The hard outer covering of a tooth is called enamel . Tooth animal is the hardest material in our body. The part of a tooth below enamel Called Dentine. The pulp cavityContains nerves and blood vessels.
_When we eat sugary food, the bacteria in the mouth act on sugar to produce acid. The acids first dissolve the calcium salts from the tooth enamel and then from dentine and form small cavities in the tooth over a period of time.
_The formation of cavities reduce the distance between the outside of the tooth and pulp cavity. The acid produced by bacteria irritate the nerve ending inside the tooth and causeS Toothache.
_If cavities caused by dental decay are not cleaned and filled by a dentist the bacteria will get into the pulp cavity of tooth causing inflammation and infection leading to severe pain.
_If the teeth are not cleaned regularly they become covered with the sticky yellowish layer of food particles and bacteria cells called dental plaque. Since plaque covers the teeth forming a layer over them, The alkaline saliva cannot reach the tooth surface to neutralise the acid formed by bacteria and hence tooth decay sets in

Question 51

True or false- Small intestine is the site of absorption of water from indigestible food

Answer 51

False; large intestine..

Question 52

Explain the transport of O2 and CO2 in human beings

Answer 52

During respiration, about 97% of oxygen is transported by Red Blood Cells in the blood and the remaining 3% gets dissolved in the plasma.
Haemoglobin transports oxygen molecule to all the body cells for cellular respiration.
The haemoglobin pigment present in the blood gets attached to O2 molecules that are obtained from breathing and thus forms oxyhaemoglobin.
This oxygenated blood is then distributed to all the body cells by the heart.
After giving away O2 to the body cells, blood takes away CO2 which is the end product of cellular respiration and blood becomes de-oxygenated.
Transport of carbon dioxide

Since haemoglobin pigment has less affinity for CO2, it is mainly transported in the dissolved form.
This deoxygenated blood gives CO2 to lung alveoli and takes O2 in return.
Around 20-25% of carbon dioxide is carried by haemoglobin as carbamino-haemoglobin.
7% is in a dissolved state in the plasma and the remaining is carried as bicarbonate. Again, the binding of carbon dioxide with haemoglobin is related to the partial pressure of carbon dioxide, and the partial pressure of oxygen.
As mentioned earlier, the partial pressure of carbon dioxide is high in the tissues and this is where more binding of carbon dioxide occurs.
In the alveoli where the partial pressure of oxygen is high, carbon dioxide gets dissociated from carbamino-haemoglobin.
So, the bicarbonate formed at the tissues releases carbon dioxide at the alveoli.

Question 53

Describe aerobic respiration

Answer 53

It is a process in which there is complete break down of food (glucose) into carbon dioxide and water in the presence of oxygen and energy is released.Breakdown of pyruvate using oxygen takes place in mitochondria. This process breaks up the three carbon pyruvate molecule to give three molecules of carbon dioxide and water.

Question 54

What r respiratory substrates

Answer 54

URespiratory substrates are the organic compounds which are used in respiration to provide energy. Most common respiratory substrate is glucose.

Question 55

Describe Anaerobic respiration

Answer 55

It is the partial breakdown of food without using the molecular oxygen. In this type of respiration very less amount of energy is produced. It also includes glycolysis which takes place in the cytoplasm. During this process one molecule of glucose is degraded into two molecules of pyruvic acid (pyrusate) and little energy (2 ATP) is produced. The pyruvic acid is further broken down into two different manners:

1) alcoholic fermentation 2) anaerobic in muscle
1) Alcoholic fermentation: It is the kind of anaerobic respiration in which the organisms like yeast break down glucose into ethanol alcohol and carbon dioxide and erergy is released
2) Human muscles cells make ATO by lactic acid fermentation, when oxygen is scarce. This occurs during the time of vigorous exercise, when the demand is f oxygen by muscle is greater than the Supply. Here pyruvate is converted into lactic acid, a three carbon molecule

Question 56

True or false

Plants respire only through leafs by simple diffusion

Answer 56

False, through all of their indivual parts like leaf, stem and root. They have gaseous exchange with atmosphere by simple diffusion.

Question 57

On what does direction of diffusion spend upon?

Answer 57

Environmental conditions n requirement of plant

Question 58

What causes cramps or muscle fatigue

Answer 58

Human muscles cells make ATO by lactic acid fermentation, when oxygen is scarce. This occurs during the time of vigorous exercise, when the demand is f oxygen by muscle is greater than the Supply. Therefore the muscles switch from aerobic respiration to anaerobic respiration resulting in the formation of lctic acid and this lactic acid accumulate in muscles

Question 59

Explain the gaseous exchange in stomata

Answer 59

O2 enters into the plant body through the stomata by the process of diffusion and then goes in other cells of leaf

Question 60

Why a plant may die if this soil is waterlogged

Answer 60

because soil is unable to supply sufficient oxygen to the roots. Under these conditions root will respire anaerobically producing alcohol

Question 61

Why do fishes die when taken out of water

Answer 61

Fishes have gills as the respiratory structures which can take in only dissolved the oxygen from water. So outside the water they cannot respire

Question 62

Describe the respiration in human beings

Answer 62

1) . Human Respiratory system begin from the nose. Then the air goes into the nasal cavity.
2) The nasal passages are highly vascularised, have fine hairs and mucus secreting cells, so that the inspired air gets warmed,moistened n becomes dust free. And the clean air goes into the lungs
3) from the Nasal passage, air enters to pharynx, the part between mouth and wind pipe, and then goes into wind pipe. Tracheae doesn’t Collapse even when there is no air in it because it is supported by C shaped cartilaginous rings.
4) The trachea runs down the neck and divide two smaller tubes bronchi which are connected to lungs. The lungs lie in the chest cavity or thoracic cavity enclosed in a double member and called pleura which is separated from abdominal cavity by a muscular partition called diaphragm.
5) each bronchus divides into lungs to form a large no of smaller tubes called bronchioles.
6) the pouch like air sacs at the ends of the smallest bronchioles are called alveoli. The walls of alveoli are very thin and are surrounded by very thin bloom capillaries.
7) At alveoli the gas exchange takes place and so alveoli is called the structural and functional unit of lungs

Question 63

How does the exchange of gases in alveoli take place

Answer 63

The inhaled air in the alveoli has higher oxygen concentration than that in the blood. Blood hence, the oxygen defuses from alveoli into the blood. It passes first into the blood plasma and then combines with haemoglobin in the red blood corpuscles to form oxyhaemoglobin. Carbon dioxide in the blood capillaries is in the higher concentration Then that in the alveoli. Therefore CO2 defuses from the blood into the alveoli. CO2 is more soluble in water than oxygen hence CO2 is mostly transported in the dissolved form in our blood

Question 64

What is haemoglobin and why is it necessary

Answer 64

Haemoglobin is a respiratory pigment present in RBC Which has high affinity to oxygen. Human blood is red because of the protein hemoglobin, which contains a red-colored compound called heme that’s crucial for carrying oxygen through your bloodstream. Heme contains an iron atom which binds to oxygen; it’s this molecule that transports oxygen from your lungs to other parts of the body. It is present because when the body size of an animal is large diffusion pressure alone cannot take care of oxygen delivery to all parts of the body. Like if diffusion what to move oxygen in the body, it is estimated that it would take three years for one molecule of oxygen to get toes from our lungs

Question 65

Explain the gas is exchange in aquatic animals

Answer 65

The rate of breathing in aquatic organisms is much faster than that of organisms because water has low content of oxygen than air. Fish takes dissolved oxygen from water And forces it past the gills where the dissolved oxygen is taken up by the blood and carried to all parts of the fish and carbon dioxide produced by respiration is brought backby the blood into the gills for expelling into the surrounding water

Question 66

True or false- During the breathing cycle the lungs exhale all the air

Answer 66

During the breathing cycle, when air is taken in and let out, the lungs always contain a residual volume of air so that there is sufficient time for oxygen to be absorbed and for the carbon dioxide to be released

Residual volume (RV) is the amount of air remaining in the lungs at the end of a maximum expiration. In adult-12-14/min

Rate of breathing:
In children - 18-22/min
In adolescents - 14-18/min
In adult- 12-14/min

Question 67

Define breathing. And what is the average breathing rate in human

Answer 67

The stage of respiration in which the air is inhaled into the lungs through the mouth or nose due to muscle contraction and exhaled sure to relaxation
The avg breathing rate in an adult human at rest is about 12-16 times per minute.

Question 68

What is in halation and exhalation

Answer 68

Inhalation is the intake of fresh air from the outside into the alveoli of the lungs . It occurs by the expansion of lungs which is brought about by the enlargement of thoracic cavity. Steps-
1) The diaphragm contracts so that the diaphragm lowers down and becomes flat.

2)The external intercostal muscle contract so that the ribs and sternum Are pulled upwards and out word. This causes enlargement of cavity and resulting in expansion of lungs on. Expansion of lungs reduces the pressure of air inside so that the fresh air is called from outside into the lungs passing through the nostrils, trachea and bronchi.Fresh air has rich supply of O2 as a result the blood in theCapillaries become loaded with oxygen and expels carbon dioxide into alveoli

Exhalation is the mechanism of breathing out carbon dioxide. During exhilaration the muscles of diaphragm relaxes so that the diaphragm becomes dome shape. The external intercostal muscles also relax and the sternum comes down one and inward. Contraction of lungs increases the air pressure so that the foul air moves out.

Question 69

How is smoking injurious to health

Answer 69

The upper part of respiratory tract is provided with small hair like structures called Cilia . The Celia helps to remove germs, dust and other harmful particles from inhaled air. Smoking destroys these hairs due to which germs, dust and smoke enter the lungs and cause infection, cough and even lung cancer

Question 70

What are the gap adaptions for gashes exchange in the terrestrial organisms

Answer 70

Large surface area to get enough oxygen, thin permeable membrane for easy diffusion of gases, abundant blood supply for transporting respiratory gases, In order to protect the surface but the exchange occurs it is usually placed within the body, so that they have to the passages that will take care to this area. In addition to this there is a mechanism for moving the air in and out of this area where oxygen is absorbed

Question 71

Give a gist how transportation takes place organisms in advance forms like algae, protozoa, sponges.

Answer 71

The size of organism ensures that cells are not so far from each other. The uptake of materials from the environment is through the general body surface in transport within the cells is my diffusion

Question 72

Define circulation

Answer 72

Circulation is the process of transporting the absorbed food, gas, water, waste products from one place to another in the body. And human circulatory system is divided into two systems- Blood circulatory system and lymphatic system

Question 73

Why does heart has different chambers

Answer 73

To prevent the oxygen rich blood from mixing with the carbon dioxide rich blood

Question 74

What is the. Coronary circulation

Answer 74

The coronary circulation is the circulation of blood in the blood vessels that supply the heart muscles. The food and the oxygen requirement of heart wall are high in the view of its constant beating

Question 75

How many litres of blood through the body? Also give its composition.

Answer 75

5l.
Blood is thicker and slightly heavier than water. Its pH ranges from 7.35 to 7.45
The blood consist of four parts: plasma, red blood cells, white blood cells and platelets.
This blood has 50-55% of plasma and 40 to 45% of cellular components like red blood cells, white blood cells and platelets.
Plasma as 95-92% of water, 7% of protein and 1% other (hormones, Waze, gases and salts)

Question 76

What is the function of red blood cells, white blood cells and platelets

Answer 76

Red blood cells Transport o2 from lungsTo All tissues of the bodyAnd return carbon dioxide back to the lungs.
White blood cell is protect us against the Infections and diseases.
Platelets – small plate shaped cells that closer together to help in the forming blood clots when bleeding occurs

Question 77

What are the functions of blood

Answer 77

•Transport Oxygen from lungs to tissues.
•Transport carbon dioxide from tissues to lungs.
•Transferred excretory materials from tissues to kidneys.
•Transport Digested foodfood from small intestine to tissue
•Distribution of hormones and enzymes. •Formation of clot
s to prevent blood loss. •Distribution of heat and temperature control. • •Prevention from infections and helps in wound healing.

Question 79

Differentiate between the blood vessels

Answer 79

DIRECTION OF BLOOD FLOW-
• Arteries-Take blood away from heart to different parts of body.
• veins- bring the blood towards the heart from various body parts.
• Capillaries- Blood flows from arterioles to capillaries and then to venules. Exchange of material between the blood and tissue cells take place at capillaries.

KIND OF BLOOD-
• Arteries- Oxygenated blood xcept in pulmonary artery
• Veins- Deoxygenated blood except in pulmonary vein.
• Capillaries- Blood changes from oxygenated to deoxygenated.

BLOOD PRESSURE-
Artery- High
Vein- low
Capillaries- xtremely low

BLOOD FLOW
artery- Blood flows rapidly with jerks
Veins- flows smoothly without jerks
capillaries- smoothly without jerks

LUMEN-
artery- Narrow
Vein- wide
capillaries- very small

WALLS-
artery- thick and elastic
vein- thin and less elastic
Capillaries- very thin.

VALVES
arteries- absent
vein- present
Capillaries - absent

Location-
arteries- mostly deep seated
vein- mostly superficial
Capillaries- form a network all over the body n in the organs

Question 80

Write a short note on Erythrocytes.

Answer 80

In humans RBCs or erythrocytes are circular, biconcave and of 7um diameter and 2um thickness and are enucleated.
the young RBC has nucleus but an adult one lacks nucleus, mitochondria, ribosome ,endoplasmic reticulum.
in adults they are produced in the red bone embryo they are formed in liver and kidney which later in ones life(adult) act as the graveyard of RBCs
the respiratory pigment, hemoglobin imparts red color type of cells(haema=iron, globin=protein).haemoglobin has the highest affinity to carbon monoxide followed by oxygen and co2 to some extent.
RBCs are about 4.5-5million in one cubic millimeter of blood. they have a lifespan of about 120 days.

Question 80

T/F -Capillaries lack muscular walll

Answer 80

T ; they lack muscular wall and is line by simple squamous epithelium (endothelium

Question 81

What is heart and where is it located

Answer 81

The heart is a muscular cone shaped organ about the size of a clenched fist of the same person. It is located in the upper body between the lungs and with its broad base facing upward and backward and the narrow apex directed downwards, forwards and slightly towards the left. It is enclosed in tough, two layer sac, pericardium

Question 82

write a short note on leucocytes

Answer 82

White blood cells , also called leucocytes are nucleated with rounded and irregular shape. many of the wbcs are made in the bone marrow.
they can change shape and are capable of amoeboid movement .
Diapedesis is t5he process through which WBCs squeeze out of the capillaries into tissue to fight the antigens.
they are around 5000-8000 per cubic millimeter of blood but there count might increase when they are in requirement in the body.
They live for few hours to many days depending in their type.
there are two main types of WBC and total 5-
GRANULOCYTES AGRANULOCYTES
I_ neutrophils I_ lymphocytes
I_ basophils I_ monocytes
I_ Esinophils

Question 83

Describe the structure of heart

Answer 83

The heart is divided into separate right and left sections by the septum or Sapta.
Each of these sections is also divided into upper and lower compartments known as atrium/auricle and ventricle respectively.
The four main chambers of heart are: right atrium, right ventricle, left atrium, left ventricle.

It is essential that blood flows in the correct direction through the heart so the structure of the heart includes a series of valves.
•The tricuspid valve( Atrioventricular valve) Separates the right atrium from right ventricle.
• The pulmonary valve( semilunar valve)Separate right ventricle from the pulmonary arteries.
• The mitral also known as bicuspid valve is the atrioventricular valves which separates the left atrium from left ventricle.
• The aortic valve (semilunar valve) separates the left ventricle from aorta

Question 84

what is blood clotting and why does the blood not clot inside blood cells

Answer 84

When we are injured or start bleeding, the loss of food from the system has to be minimised. In addition, leakage will lead to a loss of pressure which would reduce efficiency of the pumping system. To avoid this, Blood has platelets with circulate around the body and plug these leakages by helping to clot the blood at these points of injuries. In blood plasma, the basophil cells Secrete heparin, Which is an anti-clotting chemical. Heparin prevents the blood from clotting within the blood cells

Question 85

Describe the working of the heart

Answer 85

The heart functions as Pump in circulatory system the right atrium collect deoxygenated blood from the two large Veins, superior and inferior vena cava
When the atrium contracts the blood is pumped through the tricuspid valves into the right ventricle.
As the right ventricle contracts the tricuspid valve closes and the blood is pumped into the pulmonary arteries through the pulmonary valve.
Pulmonary artery carries the blood to the lungs carbon dioxide is exchange for oxygen
The left atrium receives the oxygenated blood via pulmonary veins
When the left atrium contracts blood enters into the left ventricle through bicuspid valve. Then the Left ventricle contracts blood Is formed into aorta through aortic valve.During the contraction of left ventricle the mitral valve get closed to prevent backward flow into atrium.

Question 86

_____ is th largest artery and __ __is the largest vein

Answer 86

Artery- Aorta

Vein-Vena cava

Question 87

Why do ventricles have thick muscular walls than atria

Answer 87

Since ventricles have to pump blood to the various organs of the body They have thicker muscular walls

Question 88

What are you two types of blood vascular system

Answer 88

The two types of blood vascular system are: Open and closed
Open: The blood comes in direct Contact with tissue cells. Blood vessels arising from the heart pour blood into tissue spaces called sinuses. Examples arthropods.
Closed: the blood remains in the blood vessels during its entire trip around the body and never comes in contact with the tissue cells. For example all the vertebrates

Question 89

What is Systematic circulation and pulmonary circulation?

Answer 89

Systematic circulation: in This blood completes its circulation from
left to right auricle through the body organs. Oxygenated blood from the lungs– – Heart – – systematic arteries – body parts – systematic veins – heart

Pulmonary circulation: in this led to complete its circulation from right ventricle to left auricle through the lungs. Deoxygenated blood – heart-pulmonary artery-lungs-pulmonary veins-heart

the right portion of the heart is called pulmonary heart and it has D oxygenated blood. Left Portion of the heart is known as systematic heart and it has oxygenated blood

Question 90

Human heart remains functional even after death. Explain

Answer 90

The heart does continue to beat
A for many hours if kept in a nutritive oxygenated fluidbecause the contractions of the cardiac muscle begin with the muscle itself and can occur independently of any nerve supply

Question 95

Differentiate between pulmonary and systematic circulation

Answer 95

PULMONARY circulation : is a shorter circulation
SYSTEMATIC circulation: larger circulation
PULMONARY circulation: circulation between the heart and the lungs
SYSTEMATIC : between heart and remaining parts of lungs except lungs.
PULMONARY:B= blood id pumped by the the right part of the heart and received by the left part
SYSTEMATIC: blood is pumped by thelaft pat and received by the right part
PULMONARTY: pumps deoxygenated blood
SYSTEMATIC: pumps oxygenated blood
PULMONARY: brings back oxygenated blood back to heart
SYSTEMATIC: brings back deoxygenated blood. Hi

Question 96

differentiate between single circulationa nd double circulation.

Answer 96

SINGLE: blood through heart once
DOUBLE; blood through heart twice

SINGLE; only deoxygenated blood
DOUBLE: both oxygenated n deoxygenated

SINGLE : heart pumps blood only to the organ where oxygenation is to occur
DOUBLE: heart pumps blood to both oxygenating organs and rest of the body

SINGLE: pressure ofblood is low
DOUBLE: pressure of blood is high

SINGLE: metabolic rate is low
DOUBLE: metabolic rate is high

SINGLE: found in pisces
DOUBLE: found amphibians, reptiles,birds and mammals.

Question 97

What is the advantage of four chambered heart

Answer 97

four chambereed heart ensures complete separartion of oxygenated and deoxygenated blood, which is useful to animals with high energy needs(due to thermoregulation and higher activity) such as birds and mammals

Question 98

What is blood pressure

Answer 98

The force that exerts against the wall of a vessel is called blood pressure.
This pressure is pressure is greater in arteries than veins.
The systolic blood pressure is high at the time of maximum contractions of ventricles. normal value- 120mmHG
the diastolic blood pressure is maximum at the time of relaxation of ventricles. normal value- 80mmHg.
Blood pressure is measured using the instrument called sphygmomanometer.

Question 99

What is high blood pressure and what causes it

Answer 99

high blood pressure is also called hypertension and is caused by constriction of arterioles, which results in increased resistance to blood flow. It can lead to rupture of an artery and internal bleeding.

Question 100

what are capillaries

Answer 100

the smallest vessels haves walls which are one cell thick and are called capillaries. Exchange of material between the blood and the surrounding cells take place across the thin wall. The capillaries then join together to form veins that convey the blood away from the the organ or tissue.

Question 101

write a short note on lymphatic system

Answer 101

it is an open circulatory system. It consists of lymphatic capillaries, lymphatic vessels, lymph nodes, and lymphatic organs. Lymph flows from one direction only i.e. from tissues to heart.
Capillaries have fine pores through which blood plasma filters out and starts flowing into the intercellular spaces.. This fluid is celled extracellular fluid. A part of this fluid enters into the lymph capillaries. The fluid inside the lymph capillaries is called lymph. Lymph is the transparent fluid which contain blood plasma except blood proteins, RBCs and platelets.
Lymph enters into lymph capillaries which join together to form large lymph vessels The lymph vessels finally drains lymph into large veins.
The lymphatic nodes occur at intervals in the course of lymphatic vessels. It contain lymphocytes, plasma cells and macrophages. The lymph filters through the lymphatic nodes. The macrophages remove micro-organism, cellular debris and foreign particles.

Question 102

what is ECG and Pacemaker

Answer 102

ECG (electrocardiography) is the process of recording the electrical activity of the heart over a period of time using electrodes placed on the skin.
Pace maker is the machine, inserted in heart patients whose heart does not beat normally. It takes the place of specialized muscles that initiate heartbeat.

Question 103

what are the functions of lymph

Answer 103

1) It takes up the excess fluid that has diffused out from the blood capillaries and puts it into blood.
2) has lymphocytes which fight against germs and bacteria produce antibodies to fight against the infections.
3) It absorbs and carries digested food from the intestine, serves as a middle man between blood n body

Question 104

true or fasle: Blood flow and lymph flow is unilateral

Answer 104

false, blood flow is bidirectional and lymph flow is unidirectional.

Question 105

why do plants have low energy needs?

Answer 105

Plants do not
move, and plant bodies have a large proportion of dead cells in many
tissues. As a result, plants have low energy needs, and can use relatively
slow transport systems. The distances over which transport systems
have to operate, however, can be very large in plants such as very tall
trees

Question 106

write a short note on ascent of sap

Answer 106

planst absorb water fom the soil through roots. Thus the water has to transported upwards to the other parts of the body. This upward movement of water is called ascent of sap. It is called sap as it contains many dissolved minerals. Ascent of sap involves root pressure and transpirational pull. Ascent of sap is carried out by xylem tissue which consists of _
1)xylem vessels, 2xylem tracheid,
3xylem fibers 4. xylem parenchyma.
In flowering palnts xylem vessel sand tracheid conduct water and minerals upwards.
In non- flowering plants vessels are absent, tracheid are the only conducting cells

Question 107

Explain how water and minerals are absorbed by the roots?

Answer 107

The main water and mineral absorbing organ are root hairs. The root hairs are directly in contact wuth the film of water in between the soil particles. Water gets into the root hairs by the process of osmosis. At the roots, cells in contact with the soil actively take up ions(actively means by energy expenditure). This creates a difference between root and soil. Water therefore moves into the root from the soil. Here due to evaporation of water molecules from the cells of leaves there is the formation of suction which pulls water from the xylem cells of roots, creating a column of water that is steadily pushed upwards, from cortex to endothermis , and from endothermis to xylem vessels and tracheid. This is called lateral transportation. Finally the water and minerals from the vessels and tracheid move upward by the process called ascent of sap.

Question 108

What is root pressure

Answer 108

the pressure with which water is pushed up by teh xylem of the roots is called the root pressure. that is developed in the xylem due to metabolic activities of the root cells. It explains the transportation of food and water in herbaceous plants but in tall plants root pressure is insuffiecient.

Question 109

T/F majority of the component of xylem are living

Answer 109

F; out of xylem vessels, tracheid, parenchyma and fibers only xylem parenchyma is living while all other are non living and r lignified.

Question 110

T/F- vascular bundles are continuous and form an unbroken system

Answer 110

T

Question 111

what is cohesion

Answer 111

cohesion is the molecular attraction by which the particles of a body are united throughout the mass.

Question 112

What is transpiration and transpiration pull and tell in its functions

Answer 112

The loss of water in the form of water vapor from the aerial parts of the plant is called transpiration. Transpiration mainly occurs through stomata (about 80%-90%) but it may also occurs through cuticle(9%) and lenticels(1%)
The main force responsible for upward movement of water is transpiration pull generated in the leaves which the water column filled in the xylem tracheid and vessels. During day period cohesion force( attractive force between water molecules and transpiration pulls helps in the upward movement of sap from the roots to leaves.
Function- helps in the absorption and upward movemnt of water.
it helps in temperature regulation. The plant are protected from the burning due to transpiration. Evaporation produces cooling effect

Question 113

why is the effect of root pressure in transport of water more important at night?

Answer 113

during th day when the stomatas are open , the transpirational pulls become the major driving force in the movement of water in xylem.

Question 114

T/F- most transpiration takes place from the lower surface of leaf as compared to upeer

Answer 114

T because most of the stomatas are present in the lower surface.

Question 115

what is translocation?

Answer 115

transport of soluble products of photosyntheis , sugar, amino from leaves to different parts of the plant is termed translocation.. The translocation of food and other substances takes place in the sieve tubes with the help of adjacent companion cells both
in upward and downward directions depending on te need of the plant.

Question 116

describe the mechanism of translocation.

Answer 116

TRanslocation takes place with energy consumption in the form of ATP.
sugar(sucrose) made in the leaves are loaded into sieve tubes of phloem using energy from ATP.
This increases the osmotic pressure of the tissue
causing water to move into sieve tubes containing sugar through osmosis.
soluble materials r then transferred from phloem tissue to other tissues which have less pressure than in the phloem.
Thus accord to plant requirement the material is translocated from higher osmotic pressure to lower osmotic pressure areas.

Question 117

What is osmotic pressure

Answer 117

Osmotic pressure is the force that a dissolved substances exert on a semipermeable membrane through which it cannot penetrate, when separated by it from pure solvent

Question 118

T/F - inphloem All the cells except the sieve tube are living

Answer 118

The phloem tissue consist of four components – Seve tubes, companion cells, phloem parenchyma , phloem fibres.
And phloem tissue all except the phloem fibres are living cell. the mature sieve tube elements do not have nucleus

Question 119

Why is excretion necessary

Answer 119

Metabolic reactions occurring in animal body produces certain nitrogen containing materials which are of no use in the cells they are called nitrogenous waste materials. They are formed from the breakdown of proteins and nucleic acid. They become toxic if allowed to accumulate in the body. Therefore these materials must be removed from the body for healthy life. The elimination of nitrogen Waste products from the animal body to regulate the composition of the body fluids and tissues is called excretion

Question 120

What are excretory organs. What are the excretory structure and the waste product in amoeba, hydra, flat warm, earthworm, insects like cockroaches and all vertebrates

Answer 120

Excretory organs are the organs which removes the waste products of metabolism from the animal body. In single celled organisms, waste products are discharged directly by diffusion through the surface of the cell
Amoeba – strcture- Cellular surface
      -Waste product-  Ammonia 
hydra –  strcture - body surface
       -waste product – ammonia
Flatworm- Structure-protonephridia (flame cells) 
        Waste product – mainly ammonia
Earthworm – structure- nephridia 
    Waste product-ammonia or urea
Insects-structure- malpighian tubules 
  Products-urea
All vertebrae- structure-  kidneys 
                      - Products- ammonia, urea or uric acid

Question 121

What are Ammonotelic , Ureotelic and Uricotelic organism?

Answer 121

Ammonotelic organism are those which excrete ammonia e.g, most aquatic animals like bony fishes, tadpole stage in frog.
Ureotelic Organisms are those with excrete urea for example cartilaginous fishes like sharks, frogs and mammals.
Uricotelic organism or those with excrete uric acid for example reptiles birds and insects

Question 122

How does the skin helps in the regulation of body temperature

Answer 122

The thick layer of fat cells in the dermis of the skin insulates the body. Contraction of smooth muscles attached to him forms goosebumps and creates insulating blanket of warm air. Also sweat produced by sweat glands uses excessive body heat to evaporate providing a cooling effect

Question 123

What is kidney.? State its function and also describe its internal external structure

Answer 123

Kidney is the primary excretory organ, its primary function is the removal of metabolic waste thereby maintaining homoeostasis of the body. It is dark red in colour and has been shaped weighing around 125-170 g. It is located laterally either side of the vertebral column.
FUNCTIONS - To remove the poisonous substances like urea, other waste salts and excess water from the blood and excrete them in the form of yellowish liquid called urine.
EXTERNAL STRUCTURE – • each kidney is surrounded and covered by a tough, fibrous, capture of connective tissues. This capsule is called Renal capsule.
• Lateral surface of the kidney is convex one medial surface is concave. On the inner border of each kidney is a depression called hilus/ hilum
INTERNAL STRUCTURE- • The internal structure of kidney is can be divided into two parts. Its outer part is called cortex and inner part is called Medulla.. A kidney is composed of numerous microscopic coiled tubules called nephrons or uriniferous tubules

Question 124

Why are human kidney not located at similar positions

Answer 124

Due to presence of liver above the right kidney, so that the right kidney gets slightly lower position

Question 125

What are the accessory excretory organs

Answer 125

There are some other organs, such as lungs, liver, intestine and skin that remove certain metabolic waste for example carbon dioxide, sweat, oil etc. They are known as accessory or additional excretory organs