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Explain Deformities of skeleton.

Deformities Of Skeleton

Human skeleton supports an upright body. Sometimes our skeleton system becomes weak and results in deformations. The causes of the deformations are available e.g.

 Genetics Causes

Cleft Plate, a condition in which palatine processes of maxilla and palatine fail to fuse. The persistent opening between the oral and nasal cavity interferes with sucking. It can lead to inhalation of food into the lungs causing aspiration pneumonia.

Microcephaly, the small sized skull is caused by some genetic defect.

 Arthritis covers over 100 different types of inflammatory of degenerative diseases that damage the joints .

Osteoarthritis, is the most common chronic arthritis, which is a degenerative joint disease also caused by genetic defect.

Hormonal Causes

Osteoporosis is a group of diseases in which bone resorption out paces bone deposit. In this case bone mass is reduced and chemical composition of the matrix remains normal. Osteoporosis mostly occurs in aged women, which is related to decreased estrogen level. Other factors which may contribute include, insufficient exercise, diet poor in calcium and protein, smoking. etc.

Estrogen replacement therapy offers the best protection against osteoporotic bone fractures.

Nutritional Causes

Osteomalcia (soft bone) includes a number of disorders in which the bones receive inadequate minerals. In this disease, calcium salts are not deposited and hence bones soften and weaken. Weight bearing bones of legs and pelvis bend and deform. The main symptom is the pain when height is put on affected bones.

Rickets is another disease in children with bowed legs and deformed pelvis. It is caused by deficiency of calcium in diet or vitamin 'D' deficiency. It is treated by vitamin 'D' fortified milk and exposing skin to sunlight to cure disorder.

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Write a note on joints.

 Joints

Joints occurs where bones meet. They not only hold our skeleton together, but also gives it the mobility. Joints have three categories.

1. Immovable joints
2. Slightly movable joints
3. Freely movable joints

Freely movable joints also have three types.

1. Hinge joints
2. Ball and socket joint

Joints also classified on the basis of the structure.

• Fibrous Joints:

                             These joint are held together by short fibers embedded in connective tissues. Such joints are present in the skull, and they fix teeth into the jaws. 

• Cartilaginous Joints:

                                              These joints allow little or no movement . Hyaline cartilage forms joint between growing bone. The bones held together by fibrous cartilage are found between vertebrae at the point where coxal bones meet in front of the pelvis.

• Synovial Joints:

                                     These joints contain a cavity filled with fluid and are adapted to reduce friction between the moving joints. The joint is surrounded by a layer of connective tissues called "Fibrous Capsule"  and their inner layer the synovial membrane. Some parts of capsule may be modified to form distinct Ligament, holding the bones together.

Based on the structure and movement allowed, the synovial joints can be classified further into major categories.

Synovial joints

•  Hinge Joint:

                              The joint that allows the movement in two directions. These are at elbow and knee. At these joints, pair of muscles are arranged in the same plane as that of joints. One end of each muscle, the origin is fixed to the immovable bone on one side of the joint and the other end of muscles, the the insertion is attached to the far side of the joint.

•  Ball & Socket joints:

                                              The joint that allows the movement in several directions. Such joints have at least two pairs of muscles present perpendicular to each other. They provide maximum flexibility. Hip joint and shoulder joint are the examples of ball & socket joints.

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Explain commercial application of plant hormones.

 Commercial Applications

Commercial Application

Auxins

• Discovery of IAA led to the synthesis of wide range of compounds by chemists. The synthetic auxins are economical than IAA to produce and often more active because plants generally do not have necessary enzymes to break them down.

Synthetic Auxins:

• NAA ( Naphthalene acetic acid)
•  Indole propionic acid

Stimulates fruiting- help natural fruit set. Sometimes causes fruit setting in absence of pollination (Parthenocarpy).

• 2,4D (2,4 Dichloro phenoxy acetic acid)

Selective weed killer. Kills broad leaved species (dicots). Used in cereal crops and lawns to eliminate weeds.

Inhibits sprouting of potatoes.

Prevents premature fruit drop ( retard abscission).

Gibberellins

• GA promote fruit setting e.g. in tangerines and pears and are used for growing seedless grapes. (Parthenocarpy) and also increase the berry size.

• GA3 is used in the brewing industry to stimulate a-amylase production in barely and this promotes malting.

• To delay ripening and improve storage life of bananas and grape fruits.

Cytokinins 

• Cytokinins delay aging of fresh leaf crops, such as cabbage and lettuce (delay of senescence) as well as keeping flowers fresh. They can also be used to break dormancy of some seeds.

Abscisic Acid

•  Abscisic acid can be sprayed on tree crops to regulate fruit drop at the end of the season. This removes the need for picking over a large time- span.

Ethene

•  Ethene induces flowering in pineapple. Stimulates ripening of tomatoes and citrus fruit. The commercial compound ethephon break down to release ethene in plants and is applied to rubber plant to stimulate the flow of latex.

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Write down plants hormones.

 Plant Hormones

Some of the special substances produced by the plants which influence the growth and plant responses to various stimuli are given below.

Plant Hormones

(a) Auxins:

• In stem, promote cell enlargement in region behind apex. Promote cell division in cambium.

• In roots, promote growth at very low concentration. Inhabit growth at higher concentration e.g. geotropism. Promote growth of roots from cuttings and calluses.

• Promote bud initiation in shoots but sometimes antagonistic to cytokinins and is inhibitory.

• Cause delay in leaf senescence in a few species.

(b) Gibberellins:

• Promote cell enlargement in the presence of auxins. Also promote cell division in apical meristem and cambium.

• Promote "bolting" of some rosette plants.

• Promote bud initiation in shoots of chrysanthemum callus.

• Cause delay in leaf senescence in few species.

• Break bud and seed dormancy.

• Promote leaf growth and fruit growth.

(c) Cytokinins:

• Promote stem growth by cell division in apical meristem and cambium.

• Promote stomatal opening.

• Cause delay in leaf senescence.

• Inhibitory primary root growth.

• Promote lateral root growth.

• Promote bud initiation and leaf growth.

(d) Abscisic:

• Promote bud and seed dormancy.

• Promote flowering in short day plants, and inhibits in long day plants.

• Sometimes promotes leaf senescence.

• Promote abscission.

• Promote closing of stomata under condition of  water stress.

(e) Ethene:

• Inhibits root growth.

• Break dormancy of bud.

• Promotes fruit ripening.

• Promotes flowering in pineapple.

• Inhibits stem growth.

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Write a note on Ear.

 Ear

Hearing is important as vision. Our ear helps us in hearing and also to maintain the balance or equilibrium of our body.

Ear

 Ear has three parts.

• External Ear
• Middle Ear
• Inner Ear

External Ear:

                           External ear consists of pinna, auditory canal and ear drum (tympanum). 

Pinna is the broad external part, made of cartilage and covered with skin. It helps to direct sound waves into auditory canal.

There are special glands in the walls of auditory canal, which produce wax. The wax and the hairs in auditory canal protect ear from small insects, gems and dust. 

In addition to this, they help to maintain the temperature and dampness of auditory canal. Auditory canal ends in ear drum. This thin membrane separates external ear from middle ear.

Middle Ear:

                        Middle ear is a chamber after external ear. Three small bones, called middle ear ossicles, are present in a chain in middle ear. Those movable bones includes malleus, incus and stapes. 

Malleus is attached with ear drum, them comes out incus and finally stapes that is connected with a membrane called oval window. Oval window separates middle ear from inner ear. Middle ear also communicates with nasal cavity through Eustachian tube. This tubes regulates the air pressure on both sides of ear drum.

Inner Ear:

                     Inner ear consists of three parts 

• Vestibule
• Semicircular canals
• Cochlea

Vestibule is present in the center of inner ear.

Three canals called semicircular canals are posterior to the vestibule.

The  cochlea is made of three ducts and wraps itself into a coiled tube. Sound receptor cells are present within the middle duct of cochlea.

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Write a note on Spinal Cord?

 Spinal Cord

The spinal cord is in fact a tubular bundles of nerves. It starts from brain stem and extends to lower back. Like, brain, spinal cord is also covered by meninges. The vertebral column surrounds and protect spinal cord.

Spinal Cord

The outer region of spinal cord is made of white matter (containing myelinated axons). The central region is butterfly shaped that surrounds the central canal. Its made of grey matter (containing neuron cell bodies).

31 pairs of spinal nerves arise along spinal cord. These are " Mixed Nerves" because each contains axons of both sensory and motor neurons.

At the point where a spinal nerve arises from spinal cord, There are two roots of spinal nerve.

•  The dorsal root contains sensory axons and ganglion where cell bodies are located.
• The ventral root contains axons of motor neurons.

Functions:

• It serves as a link between body parts and brain. Spinal cord transmits nerve impulses from body parts to brain and from brain to body parts.
• Spinal cord also acts as coordinator, responsible for some simple reflexes.

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Who is the largest part of brain & write its part?

 Brain

Forebrain is the largest parts of brain. It is most highly developed in humans.

FOREBRAIN

Parts:

There three parts of forebrain.

• Thalamus
• Hypothalamus
• Cerebrum

Thalamus:

                    Lies just below the cerebrum. It serves as a relay center between various parts of brain and spinal cord. It also receives and modifies sensory impulses (except nose) before they travel to cerebrum. Thalamus is also involved in pain perception and consciousness (sleep and awakening).

Hypothalamus:

                                Lies  above midbrain and just below thalamus. In humans, it is roughly the size of  an almond. One of the most important functions of hypothalamus is to link nervous system and endocrine system. It control the secretions of pituitary gland. It also controls feelings such as rage, pain, pleasure and sorrow.

Cerebrum:

                      It is the largest parts of forebrain. It controls skeletal muscles, thinking, intelligence and emotions. It is divided into two cerebral hemisphere.

Cerebral hemisphere:

                                          The anterior parts of cerebral hemisphere are called Olfactory bulbs which receive impulses from olfactory nerves and create the sensation of smell. 

Upper layer: 

                        The upper layer of cerebral hemispheres i.e. cerebral cortex consists of grey matter. The grey matter of nervous system consists of cell bodies and non myelinated axons.

Lower layer:

                          This layer consists of white matter. The white matter of nervous system consists of myelinated axons.

Cerebral cortex has large surface area and is folded in order to fit in skull. It is divided into four lobes.

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Explain Neuron & Write three classification of nerve.

 Neuron

Nerve cell or neuron is the unit of the nervous system. The human nervous system consists of billions of neurons plus supporting cell. Neuron are the specialized cells that are able to conduct nerve impulses from receptors to coordinators and from coordinators to effectors. In this way the communicate with each other and with other types of body cell.

Location:

                   The nucleus and most of the cytoplasm of neurons is located in the cell body. 

Dendrites & Axons:

                                          Different processes extend out from the cell body. These are called dendrites and axons.

Dendrites conduct impulses towards cell body and axons conduct impulses away from the cell body.

Schwann cells:

                              Schwann cells are special neurological cells located at regular intervals along axons, In some neurons Schwann cell secrete fatty layer called myelin sheath.

Nodes of Ranvier:

                                   Between the areas of myelin on an axon,  there are no myelinated points called Nodes of Ranvier. 

Saltatory: 

                     Myelin sheath is an insulator so the membrane coated with this sheath does not conduct nerve impulse. In such impulses are called saltatory (jumping) impulses. This increases the speed of nerve impulse.

On the basis of the function, neuron are of three types.

• Sensory neurons
• Interneurons
• Motor neurons

Sensory Neuron:

                                  Conduct sensory information (nerve impulse) from receptors towards the CNS. Sensory neurons have on dendrite and one axon.

Interneuron:

                          From brain and spinal cord. They receive information, interpret them and stimulate motor neurons. They have many dendrites and axons.

Motoneuron:

                          Carry information from interneurons to muscle or glands (effectors). They have many dendrites but only one axon.

Nerve

 A nerve means the union of several axons that are enveloped  by covering made of lipid.

Classification:

• Sensory nerve
• Motor nerve
• Mixed nerve

Sensory nerve:

                              Contain the axons of sensory neurons only.

Motor nerve: 

                           Contain the axons of  motor neurons only.

Mixed neuron:

                              Contain the axons of both i.e. sensory and motor neurons.

Write down the steps of functionality of kidney.

 Functioning of kidney

The main function of kidney is urine formation, which takes place in three steps.

• Pressure Filtration
• Selective Reabsorption
• Tubular Secretion

Functioning of kidney 

Pressure Filtration:

                       When blood enters the kidney via the renal artery, it goes to many arterioles, and then to the glomerulus . The pressure of blood is very high and so most of the water, salt, glucose and urea of blood is forced out of glomerulus capillaries. This material passes into the Bowman's capsule and is now called Glomerulus Filtrate.

Selective Reabsorption:

                                               The second step is the selective reabsorption. In this step about 99% of the glomerulus filtrate is reabsorbed into the blood capillaries surrounding renal tubule. It occurs through osmosis, diffusion and active transport. Some water and most of the glucose is reabsorbed from the proximal convoluted tubule. Here, salts are reabsorbed by active transport and then follows by osmosis. The descending limb of loop of Henle allows the reabsorption of water while the ascending limb of loop of Henle allows the reabsorption of salts. The distal convoluted tubule again allows the reabsorption of water into the blood.

Tubular Secretion:

                                      The third step is tubular secretion . Different ions, creatinine, urea etc. are secreted from blood into the filtrate in renal tubule. This is done to maintain blood at normal pH (7.35 to7.45).

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Define urine & Explain osmoregulatory function of kidney.

 Urine

The filtrate present in renal tubules is known as urine. It moves into collecting ducts and then into pelvis.

Osmoregulatory function of kidney

Osmoregulation:

                                  Is defined as the regulation of the concentration of the water and salt in blood and other body fluids. Kidney plays important role in osmoregulation by regulating the water fluids whereas excess intake of water dilutes them.

Osmoregulation of kidney

Hypotonic:

                       When there is excess water in body fluids, kidney from dilutes (Hypotonic) urine. For this purpose, kidney filter more water from glomerulus capillaries into Bowman's capsule. Similarly less water is reabsorbed and abundant dilute urine is produced. It brings down the volume of the body fluids to normal.

Hypertonic:

                        When there is shortage of water in body fluids, kidney filter less water from glomerulus capillaries and the rate of reabsorption of water is increased. Less filtration and more reabsorption of water produce small amount of concentration (hypertonic) urine. It increases the volume of body fluids to normal. This whole process is under hormonal control.

Hypotonic & Hypertonic

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Why Kidney Stone happen & what is Renal Failure?

 Kidney Stone

When urine becomes concentrated, crystals of many salts eg calcium oxalate, calcium and ammonium phosphate, uric acid etc. are formed in it. Such large crystals cannot pass in urine and form hard deposits called Kidney Stone.

kidney stones

Most stones start in kidney. Some may travel to ureter or urinary bladder.

Causes:

               The major causes of kidney stones are age, diet (containing more green vegetables, salts, vitamins C,D), recurring urinary tract infection , less intake of water, and alcohol consumption.

Symptoms:

                      The symptoms of kidney stones include severe pain in kidney or in lower abdomen, vomiting, frequent urination and foul-smelling urine with blood and pus. 

About 90% of all kidney stones can pass through the urinary system by drinking plenty of water. In surgical treatment, the affected area is open and stones are removed.

Lithotripsy:

                       Lithotripsy is another method of removal of kidney stones. In this methods, non electrical shock waves from outside are bombarded  on the stone in the urinary system. Waves hit the dense stones and break them. Stones become sand-like and are passed through urine.

Kidney(Renal) Failure

Kidney failure means a complete or partial failure of kidneys to function.

Renal Failure

Causes:

               Diabetes mellitus and hypertension are the leading causes of kidney failure. In certain cases, sudden interruption in the blood supply to kidney and drug overdoses may also result in kidney failure.

Symptoms:

                       The symptoms of kidney failure is the high level of urea and other wastes in blood, which can result in vomiting, nausea, weight loss, frequent urination and blood in urine. Excess fluids in body may also cause swelling in legs, feet face and shortness of breath.

Treatment:

                       The kidney failure is treated with dialysis and kidney transplant.

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Write a note on Dialysis.

 Dialysis

Dialysis means cleaning of blood by artificial ways.

Methods:

                There are two methods of dialysis.

1. Peritoneal Dialysis
2. Haemo Dialysis

Peritoneal Dialysis:

                                        In this type of dialysis, the dialysis fluid is pumped for a time into the peritoneal cavity which is the space around gut. This cavity is lined by peritoneum. Peritoneum contains blood vessels. When we place dialysis fluid in peritoneal cavity, waste materials from peritoneal blood vessels diffuse into the dialysis fluid, which is then drained out. This type of dialysis can be performed at home, but must be done every day.

Haemodialysis:

                                In haemodialysis, patient's blood is pumped through an apparatus called Dialyzer. The dialyzer contains long tubes, the walls of which act as semi-permeable membranes. Blood flows through the tubes while dialysis fluid flows around the tubes. Extra water and wastes moves from blood into the dialysis fluid. The cleansed blood is then returned back to body. The haemodialysis treatments are typically given in the dialysis center.

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Write a note on structure and function of kidney.

 Structure of Kidney

Colour of kidney:

                                   Kidney are dark red bean shaped organ.

Size of kidney: 

                             Each kidney is 10cm long, 5cm width thick and weights about 120 grams.

Location:

                   They are placed against the back wall of abdominal cavity just below diaphragm , one on either side of the vertebral column. They are protected by the last 2 ribs. The left kidney is little higher than the right.

Hilus: 

            The concave side of the kidney faces the vertebral column. There is a depression called Hilus, near the Centre of  the concave area of kidney. 

Kidney shows two regions

Renal cortex:

                          is the outer part of the kidney and it is dark red in colour.

Renal medulla:

                                is the inner part of the kidney and is pale red in colour. Renal medulla consists of several cone shaped areas called renal Pyramids. Renal pyramids projects into a funnel-shaped cavity called renal Pelvis which is the base of ureter.

Structure of kidney

Function of Kidney

The function unit of kidney is called nephron. There are over one millions nephrons in each kidney. 

Parts of Nephron:

                                    There are two parts of nephron i.e. Renal Corpuscle and Renal Tubule.

Renal corpuscle is not tubular and has two parts i.e. glomerulus and Bowman's capsule. Glomerulus is a network of capillaries while Bowman's capsule is a cap shaped structure that encloses glomerulus.

Renal Tubule:

                            It is the part of nephron which starts after Bowman's capsule. Its first portion is called the proximal convoluted tubule. Next portion is U-shaped and is called Loop of Henle. The last portion of renal tubule is called the Distal convoluted tubule. 

Collecting Duct:

                                 The distal convoluted tubule of many nephrons open in a single collecting duct. Many collecting ducts join together to form several hundred Papillary Ducts which drain into renal pelvis.

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Osmotic adjustments in plants & Explain its three groups.

Osmotic adjustment in plants

On the basis of  available amount of water and salt, plants divided into three groups.

Hydrophytes:

                           Those plants which live partially submerge or completely in freshwater. Such plants do not face the problem of water shortage. They have developed mechanisms for the removal of extra water from their cells. Hydrophytes have broad leaves with a large number of stomata on their upper surfaces. This characteristics helps them to remove the extra amount of water.

Example:

                  Water lily.

Hydrophytes plants

Xerophytes: 

                        They live in dry environments. They possess thick, waxy cuticle over their epidermis to reduce water loss from internal tissues. They have less number of stomata to reduce the rate of transpiration. Such plants have deep roots to absorb maximum water from soil. 

Example:

                  Cacti (singular cactus).

Xerophytes plants

Halophytes:

                         They live in sea water and are adapted to salty environment. Salts enter in the bodies of such plants due to their higher concentration in sea water. 

Example:

                  Sea grass.

Halophytes plants

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