DIGESTIVE SYSTEM
Digestion is the procedure past times which large molecules of nutrient are broken downwardly into uncomplicated in addition to absorbable forms for exercise past times organisms.this procedure is done inward the digestive scheme also called the alimentary tract or the gastro intestinal tract(GIT). The digestive scheme include all the organs in addition to tissues in addition to glands associated amongst digestion.
Digestion may live mechanical or chemic digestion.Mechanical digestion involves the breaking downwardly of large nutrient chunks into modest units accessible to enzymes.it is done past times the teeth inward mammals, gizzards of birds,muscles inward some organisms. Chemical digestion is divided into
-----extracellular digestion
----- intracellular digestion
TYPES OF DIGESTIVE SYSTEMS
There are 2 types of digestive systems viz
Simple or incomplete digestive system
Complete digestive system/complex.
RECALL THIS TERMS; INGESTION,EGESTION,EXCRETION, MASTICATION.
FEEDING MECHANISMS
The development of multifariousness of organisms called for multifariousness inward the feeding habits, machinery in addition to modifications of oral fissure parts, this is to cut down contest for nutrient in addition to heighten survival.
Some of the organisms are herbivores; others are carnivores spell others are omnivores. H5N1 few are scavengers.
Some of import feeding habits include
*FILTER FEEDING
*FLUID FEEDING
* SAPROPHYTIC FEEDING
*PARASITIC FEEDING
Some of import feeding mechanisms include
*ABSORPTION MECHANISM EG TAPE WORM
*BITING AND CHEWING MECHANISM EG GRASSHOPPER
* SUCKING MECHANISM EG.HOUSEFLY AND BUTTERFLY
*PIERCING AND SUCKING MECHANISM EG. Female anopheles MOSQUITO
* GRINDING AND CHEWING EG MAN, SHEEP
* TRAPPING AND ABSORBING EG.SUNDEW
ALIMENTARY TRACTS OF SOME ANIMALS
EARTHWORM.
The GIT of the earthworm is a long metro amongst diverticulum at intervals to cast vital organs. it begins inward the oral fissure called a prostomium which opens into a buccal cavity in addition to to the pharynx. The throat leads to the oesophagus, crop, a muscular gizzard, intestine, caecum, rectum in addition to anus.
Earthworm feeds on dry out vegetables matter. It ingests them through the oral fissure into the throat where a lubricant moistens the food. the nutrient goes through the esophagus to the crop for storage. It moves from the crop to the muscular gizzard for grinding in addition to so to the intestine for absorption. As a consummate digestive scheme waste materials products are egested through the anus equally casts.
Digestive System inward Cockroach (Invertebrates)
Nutrition inward cockroach is holozoic in addition to it is an omnivore, feeding on dissimilar kinds of organic matter. It takes inward pieces of nutrient in addition to has to grind them earlier digesting them. Thus its oral fissure parts are modified accordingly for chewing the food.
Cockroach
The digestive scheme includes the oral fissure parts, a brace of salivary glands in addition to the alimentary canal.
Birds
The digestive system inward the domestic fowl is real uncomplicated but efficient when compared to many other species similar cattle. In the procedure of evolution, those avian species that developed uncomplicated but effective digestive systems were to a greater extent than able to wing in addition to hence move – the uncomplicated digestive scheme would real probable live lighter inward weight. Because of the simplicity inward the construction in addition to component division it is necessary that the diet provided to fowls live of high character to live easily digested specially if the birds are to attain the productive performance expected of them.. 
What does the digestive scheme consist of?
The digestive scheme consists of the gastrointestinal tract along which the nutrient passes later on eating to where the ease wastes are eliminated from the body, together amongst the liver in addition to the pancreas. The digestive scheme is responsible for the ingestion of food, its breakdown into its constituent nutrients in addition to their absorption into the blood stream, in addition to the elimination of wastes from that process.The liver produces bile in addition to is associated amongst the metabolism of nutrients together amongst a number of other functions. The master copy component division of the pancreas is the production of digestive enzymes in addition to special compounds called hormones.
The gastrointestinal tract
The gastrointestinal tract is a long metro similar organ starting at the nib in addition to ending amongst the vent or cloaca inward the abdominal region. Generally the gastrointestinal tract has layers of musculus running lengthwise in addition to around it in addition to is lined amongst mucous membranes. Glands producing of import digestive juices are flora inward dissimilar locations of the canal. The nutrients from the food, later on digestion, are absorbed through the wall of the gastrointestinal tract into the circulatory scheme for carry to the liver or other parts of the body. The waste materials remaining is eliminated from the trunk via the cloaca or vent. Mouth construction
In the fowl the lips in addition to cheeks are replaced past times the nib – an expanse of dense in addition to horny peel lying over the mandible in addition to incisive bones that serve equally the bony foundation. There are no teeth. The so called egg tooth flora on the terminate of the nib of newly hatched chickens is an aid to their escape from the egg at hatching in addition to disappears later on a twenty-four hours or two. The difficult palate, forming the roof of the mouth, presents a long, narrow median slit that communicates amongst the nasal cavity (median – along the middle). The difficult palate has 5 transverse rows of backwardly pointing, hard, conical papillae. Numerous ducts of the salivary glands pierce the difficult palate to release their secretions into the oral fissure cavity. Pharaynx in addition to natural language
The throat is continuous amongst or follows the mouth. The combined cavity of the oral fissure in addition to the throat is frequently referred to equally the oropharynx. The mutual opening for the 2 eustachian tubes is located inward the middle of its dorsal wall (roof). The natural language is long in addition to pointed in addition to conforms to the shape of the nib inward which it operates. The epithelium of the natural language is thick in addition to horny, specially towards the tip. H5N1 transverse row of simple, large in addition to horny papillae amongst their tips directed towards the nurture of the oral fissure cavity are located on the posterior end. The hyoid os provides the framework to back upwards the tongue. The entoglossal os extends longitudinally inward the median plane. modest patches of lymphatic tissue are located throughout the corium. Mucous glands are located inward the natural language amongst curt ducts directed towards the rear. Some but non others believe that in that location are sense of savor buds located on the tongue. In whatever illustration the sense of sense of savor appears to live real weak if at all present.The oral fissure has 2 major functions:
- To alternative upwards the nutrient particles.
- To direct the nutrient into the oesophagus – equally component division of the bird’s eating behaviour.
Oesophagus, crop in addition to proventriculus
The oesophagus is broad in addition to is capable of existence significantly stretched. It connects the oral fissure part to the crop inward unopen association amongst the trachea. The crop is a large dilation of the oesophagus located only prior to the oesophagus entering the thoracic cavity. The crop provides the capacity to concur nutrient for some fourth dimension earlier farther digestion commences. This capacity enables the plane to accept its nutrient equally “meals” at fourth dimension intervals but permits continuous digestion. Inside the thoracic cavity, the oesophagus enters or becomes the proventriculus – a real glandular component division of the digestive tract frequently called the glandular stomach.The wall of the oesophagus is composed of 4 layers of tissue the innermost existence mucous membrane. The mucous membrane is an of import barrier to the entry of microbes in addition to the mucous it produces is a lubricant that aids the passage of the nutrient along the alimentary canal. The construction below the crop is similar to that higher upwards except in that location is less lymphoid tissue below the crop. The crop construction is similar to that of the oesophagus except in that location are no glands introduce inward fowls. Ducks in addition to geese receive got glands inward the crop mucous membranes. In pigeons the surface cells of the crop slough off during brooding to cast pigeon’s milk – used to feed the babe pigeons inward the nest.
Proventriculus
The glandular tum or proventriculus is relatively modest in addition to tubular. The wall is real thick in addition to is composed of 5 layers:- Outer serous membrane.
- Muscle layer composed of iii separate layers:
- Two sparse longitudinal layers.
- Thick circular layer.
- Layer of areolar tissue containing blood in addition to lymph vessels.
- Thick layer composed mainly of glandular tissue.
- Mucous membrane.
Gizzard
The muscular tum or gizzard is located at in i lawsuit succeeding the proventriculus. It is placed partly betwixt the lobes in addition to partly behind the left lobe of the liver. It has a flattened, rounded shape somewhat similar a convex lens, amongst i side slightly larger than the other. Each surface is covered past times a glistening layer of tendinous tissue – thicker at the centre in addition to becoming thinner towards the edges. Under this outer layer real powerful masses of ruby musculus are located. The inner surface is lined amongst a creamy coloured, thick, horny tissue raised inward ridges. The gizzard almost ever contains quantities of difficult objects such equally gravel or other grit that aids inward the disintegration of nutrient – the primary component division of the gizzard.The entrance from the proventriculus in addition to the move out to the duodenum are unopen together in addition to dorsal inward location. The gizzard consists of a number of layers of tissues inward some of which directly tubular glands are located. The innermost layer is a strong, flexible peel able to withstand the potentially damaging effects of the muscular activeness grinding the nutrient frequently inward the presence of stones or other insoluble material. The glands of the gizzard hit a liquid, keratinised stuff that passes to the surface of the horny lining where it hardens to supplant tissue worn away past times the grinding activeness of the organ.
one twelvemonth old.
Caeca
The 2 caeca or blind pouches are virtually 16-18 centimetres long inward the adult. They extend along the line of piece of employment of the modest intestine towards the liver in addition to are closely attached to the modest intestine along their length past times the mesentery. Each caecum has iii master copy parts:- A narrow base of operations amongst thick walls arising at the ileo-colic-caecal junction
- Middle component division amongst sparse walls
- The broad blind apex amongst fairly thick walls
Cloaca
The large intestine terminates inward the front end component division of the cloaca. The cloaca is a tubular cavity opening to the exterior of the trunk in addition to is mutual to the digestive in addition to urogenital tract. The construction of the cloaca is real similar to that of the intestine except that the muscularis mucosa disappears nigh the vent. It divides into iii chambers, each separated past times a constriction non readily defined:- The copradaeum – a continuation of the colon-rectum
- The urodaeum – middle component division into which the ureters in addition to genital ducts open
- The proctodaeum – opens to the exterior of the vent. Birds less than i twelvemonth onetime receive got a dorsal opening leading into the blind, rounded sac – the bursa of fabricius
Food storage
The nutrient is delivered into the crop for storage later on the starting fourth dimension few boli receive got passed into the proventriculus. The crop is quite distensable in addition to volition concur a large amount of undigested nutrient that is so moved on equally required past times the proventriculus. This component division of the crop is less of import when in that location is a plentiful render of nutrient available. Because of the crop’s mightiness to concur a render of food, when applying a nutrient command (restriction) program, it is necessary to compensate past times providing a long menstruum of nutrient deprivation to accomplish the required marking of control. There is no human relationship betwixt the length of fourth dimension of nutrient deprivation in addition to the amount of nutrient consumed.juice from the pancreas.
Breaking the nutrient particles
The gizzard is a real powerful organ amongst the component division of physically breaking the nutrient particles into smaller sizes to brand the piece of employment of the enzymes easier. At the same fourth dimension the enzymes previously released into the nutrient amongst the saliva in addition to past times the proventriculus are thoroughly mixed into the nutrient thus improving their chance to carry out their work. This breaking in addition to mixing component division of the gizzard is enhanced past times the presence of insoluble grit such equally stones.The nutrient stuff enters the duodenum from the gizzard. Enzyme activity inward this part is, inward the main, a continuation of the breakdown of proteins started inward the
Human Digestive System
INRODUCTION TO DIGESTIVE SYSTEM IN HUMAN BODYThe digestive system is concerned amongst the breakdown of complex nutrient substances in addition to its conversion inward to simpler components , its absorption through the blood current and assimilation inward the cells in addition to tissues producing desired effects of growth etc.The digestive system inward homo comprises of dissimilar components each assigned amongst a specific function.Basically, the the digestive scheme tin terminate live considered equally a the nutrient pipage or esophagus initiating from the buccal cavity or oral fissure in addition to terminating inward the anus amongst diversifications at dissimilar stages of its progression cast the oral fissure to anus.
Components of the digestive system inward human body:
The digestive scheme in human trunk comprises of the following:
The oral fissure or the buccal cavity bounded past times the upper in addition to lower lips is the intiation of the digestive scheme inward the human body. Internally, the buccal cavity is provided amongst iii pairs of salivary glands, namely the parotid, sublingual in addition to submaxillary that produces saliva.
The flooring of the buccal cavity is provided amongst the muscular tongue amongst tastebuds that helps inward tasting in addition to mastication of the food.Man is heterodont in addition to has inscisiors(2), canine(1), premolar(2) in addition to tooth teeth (3 ,last tooth als called wisdom teeth) inward each one-half of the jaw.
In the oral fissure , the nutrient is ingested ,and masticated, mixed amongst saliva in addition to converted into bolas for swallowing past times the pharynx. Pharynx is the part where both the digestive tract in addition to the respiratory tracts bring together together.The opening of the trachea is provided amongst an opening called glottis which gets closed past times the membranous epiglottis during swallowing.It prevents entry of nutrient particles inward the trachea .If it enters accidentally, coughing reflex is initiated
OESOPHAGUS:
The oesophags is the tubular pathway leading from the oral fissure to the tum in addition to is involved ib carry of the bolas past times way of involuntary peristalsis .It is an alternate contraction in addition to relaxation of the circular in addition to longitudinal muscles that forces the food downwards.The oesophagus moves thorugh the diaphragm via oesophageal biatus in addition to enters the tum at the cardiac terminate through the cardiac sphincter.
STOMACH:
The tum is a larger sac similar organ amongst a J shaped structure.under the diaphragm.the stomach ids divided into 4 regions -Cardia, surrounding the lower esophqageal sphincter, fundus- rounded part aboveand to the left of the cardia; body- large fundamental part below the fundus in addition to the narrow inferior part called pylorus.
The Concave medial border of the tum is called the lesser curved shape in addition to the convex border is called the greater curvature. te pyloric part joins amongst the duodenum through the pyloric sphincter.
Histology:
- Composed of usual mucosa, submucosa, muscularis and serosa from lumen towards wall equally ease of the GI tract
- Gastric glands incorporate 4 type s of cells- Zymogenic(peptic) or Chief Cells,( producing pepsinogen.), Parietal cells or oxyntic cells (produces HCL, intrinsic factor, ) , Mucous cells (producing mucous), together constituting the gastric juice.The enteroendocrine cells produces tum gastrin, the hormone stimulating HCL release inward the digestive scheme inward the human body.
ti is the largest digestive gland (i.4kg) occupying most of the right one-half of the abdomen below the diaphragm in addition to is almost completely covered past times peritoneum.It is divided into 2 major lobes, larger correct in addition to smaller left lobe separated past times falciform ligament.
The ligamentum teres (round ligament) extends from the costless borde of the falciform ligament to the bellybutton (derived from the foetal umbilical cord.)The correct lobe is considered to live of an inferior quadrate lobe in addition to a posterior caudate lobe, but basing on onternal structures they belong to a greater extent than tothe left lobe.
The bile canaliculi merge to cast the the correct in addition to left hepatic ducts that unites to cast the common hepatic duct. It joins the cystic duct forming the gall bladder in addition to the 2 together cast the common bile duct, which enters the duodenum past times ampulla of Vater or hepatopancreatic ampulla.
Histology:
Hepatic lobes are made of lobules of hepatocytes inward irregular , branching interconnected plates around central vein in addition to hit bile
Between the plates are paved amongst endothelial lining called sinusoids having stellate cells-- Kupffer'scells. The hepatic portal artery, he[patic portal vein in addition to bile duct arecollectively called protal triad
GALL BLADDER :
It is a pear shaped sac about seven to 10 cms long in addition to located inward ther fossaa of the visceral surface of the liver.It is a store for bile in addition to when intestine is empty,the sphincter of hepatopancreatic ampulla or sphincter of Oddi closes .
PANCREAS:
The pancreas is an oblong ,tuboacinar gland (12.5 cmsX 2.5 cms)located posterior to the greater curved shape of the tum in addition to is unremarkably connected to the duodenum past times 2 ducts.It has a head, trunk in addition to tail.The caput is expanded in addition to nigh the C shaped bend of the duodenum.
the larger of the 2 ducts is called the pancreatic duct (duct of Wirsung) , spell the smaller i is called the accessory duct or duct of Santorini, leading cast the pancreas into the duodnum.
Histology: The pancreas consists of 2 types of cells -the pancreatic acini in addition to the pancreatic islets or Islets of langerhans.The Islets of langerhans possess the α, β, in addition to δ cells that secretes glucagon, Insulin ans somatostatin respectively. The acini hit the pancreatic juice.Pancreas is also called mixed gland.
It initiates from the pyloric terminate of the tum in addition to consists of anterior (duodenum), middle (jejunum ) in addition to terminal (ileum).this part is specialized past times the presence of numerous finger similar projections called villi amongst efferent in addition to afferent blood vessels that serves inward absorption of food equally a component division of the digestive scheme inward the human body.
LARGE INTERTINE
The large intestine or the colon initiates from the ileum of the small intestine in addition to consists of ascending ,descending in addition to transverse colon in addition to the sigmoid colon.the opening of the ileum in addition to the colon is guarded past times the ileocecal sphincter.it ends at the rectum in addition to the anus.
THE PROCESS OF DIGESTION Digestion begins inward the oral fissure in addition to terminate s inward the modest intestine.
It begins amongst the ingestion of nutrient into the oral fissure where the teeth masticates the food,saliva softens the nutrient in addition to salivary amylase(ptyalin) acts on cooked starch to convert it into maltose.the natural language at nowadays rolls the nutrient against the difficult palate into a bolus. The bolus is rolled backwards into the throat in addition to to the oesophagus.
By a moving ridge similar displace called peristalsis, the bolus moves downwardly into the gullet to the cardiac sphincter, hither the parasympathetic nerves relaxes the sphincter in addition to allow the bolus into the stomach. The presence of the bolus inward the tum triggers the release of a hormone named GASTRIN which inward plough induces the release of gastric juice.HCL,PEPSINOGEN AND RENIN are contents of the gastric juice. The churning activeness of the tum mixes the bolus amongst the juice to convert it into a semi company called CHYME. The presence of chyme allows the pyloric sphincter to relax spell the chime moves into the duodenum. Trypsin, amylopsin in addition to lipase from the pancreatic juice acts on the chyme converting it to chyle.chyle moves transcend the JEJUNUM where bile helps to emulsify the fat. At the ileum, the ‘SMELL’ enzymes from succus entericus acts on the chyle to convert it to its factor substrates.
SUMMARY OF THE DIGESTIVE PROCESS
SITE | DIGESTIVE STRUCTURE | SECRETION | ENZYME/ FLUID | SUBSTRATE | END PRODUCT |
MOUTH | SALIVARY GLAND TEETH TONGUE | SALIVA | PTYALIN | COOKED STARCH | MALTOSE |
STOMACH | GASTRIC GLAND | GASTRIC JUICE | PEPSIN RENIN HCL | PROTEIN CASEINOGEN PEPSINOGEN | PEPTONE CASEIN |
DUODENUM | PANCREAS | PANCREATIC JUICE | Trypsin Amylase lipase | Proteins/peptones Starch/carbohydrates Fats/oils | Polypeptide Maltose Fatty acids/glycerol |
jejunum | bile | Bile | Fats/oil | Emulsification | |
Ileum | Intestinal glands | Succus entericus | sucrase | Sucrose | Glucose/fructose |
maltase | Maltose | Glucose/glucose | |||
Erepsin | Polypeptide | Amino acids | |||
Lactase | Lactose/caseinogens | Glucose/galactose | |||
Lipase | Fats/oils | Fatty acids/glycerol |
ABSORPTION.
Absorption of nutrients (end products) occur inward the modest intestine. The surface of the modest intestine is thrown into folds called VILLI. These finger-like projections are covered amongst sparse epithelium in addition to highly vascularized. H5N1 large amount of mitochondria are introduce inward the microvilli to provide unloose energy for active carry of nutrients. Glucose, amino acids in addition to other uncomplicated sugars are absorbed into the blood current through the network of blood capillaries coming from the mesenteric in addition to coeliac vessels to the HEPATIC PORTAL VEIN to the liver for metabolism in addition to assimilation.
Fatty acids in addition to glycerol follow the lacteal ducts to the lymphatic vessels where they recombine to cast fats earlier entering the blood stream.
The modest intestine hence exhibit the next adaptation to absorption
- Long in addition to coiled to provide a large surface area.
- Presence of numerous finger-like villi in addition to microvilli to increment absorption
- Movement of the villi enhances their contact amongst nutrients
- They are highly vascularized to heighten diffusion
- Presence of numerous mitochondria to provide unloose energy for active transport.
TRANSPORT SYSTEM
A scheme is a collection of organs, tissues in addition to cells that performs similar functions inward an organism.
Transport is an human activeness of moving materials from i house to another. The carry scheme hence is a collection of organs, tissues in addition to cells that displace materials specially metabolic materials from diverse component division of the organism where they are produced to the parts where they are needed for use, storage or elimination from the body. As life is made upwards of dissimilar levels of scheme complexity of scheme also increases. Single celled organism similar amoeba tin terminate displace materials circular their jail cellphone past times uncomplicated procedure of diffusion. This is because
- The surface expanse to book ratio is large
- They are made of uncomplicated jail cellphone
- The distance of motion of materials is so modest hence of no organized scheme is needed
- The quantity of materials to live moves small
In the higher organism however, in that location is the involve for an organized carry scheme because
- The surface expanse to book ratio decreases
- They are made upwards of millions of cells hence greater distances are involved.
- Most cells are isolated hence they involve a linking scheme to connect them to other cells.
- Large quaintity of materials needs to live moved, diffusion lone is inefficient to displace these materials hence a involve for an organized carry system.
Importance (Need) of Transportation
Transportation is necessary to
- Move glucose from leaves where they are industry to storage organs inward plants
- Move hormones from the endocrine glands to target organs
- Move mineral tabular array salt in addition to H2O from the soil to the roots in addition to to stems in addition to leaves.
- Move metabolic waste materials similar Co2, urea etc from the tissues to the excretory organs.
- To displace nutrients from the Gill to the tissues in addition to cells for nourishment.
MATERIALS FOR TRANSPORT
PLANTS: The materials for carry inward plants include
- Manufacture nutrient from photosynthetic structures to storage
- Excretory products from the cells or tissues to excretory organs
- Water from the soil to the leaves in addition to other parts for photosynthesis
- Oxygen –Nitrogenous Products
- Amino acid –Glucose –Auxins etc
ANIMALS:
- Oxygen from the lungs to the tissues
- C02 from the tissues to the lungs
- Urea from the cells in addition to tissues to the kidney
- Water from the cells to the excretory organs
- Nutrients e.g Glucose, anion acids, obese acid from the modest intestine to the lower for metabolism in addition to from the liver to tissues in addition to cells where they are needed.
- Hormones from endocrine glands to target organs e.g Adrenalin
- Vitamins from GIT to the cells
- Antibodies from the immune scheme to the cells where they defined the trunk
- Salts from the cells in addition to tissues to the excretory organs where they are removed.
MEDIUM OF TRANSPORTATION
This stuff to live transported needs a fluid medium to displace there. The next medium are of import
1. CYTOPLASM: In unicellular organisms, the semi company cytoplasm is the medium of transport. The Cytoplasmic streaming inward organism displace materials from i house to some other E.g Amoeba, Paramecium etc.
2. CELL SAP: The cells sap of plants is devolved amongst concentration of secures in addition to other materials. It hence provide a medium of shipping for plants.
3. BLOOD: This is a liquid connector tissue that carry materials flora inward higher organism.
4. LYMPH: The lymph is a cast of tissue fluid produced from returning fluids that exape into the interstitial from spaces inward tissues. The lymph forms the transporting medium of the lymphatic scheme amino is of import inward carry antibodies, obese acids in addition to white blood cells.
Transport inward higher animals
Transport inward higher animals requires a carry scheme amongst the next features.
_ H5N1 medium of carry equivalent to the fuel inward a auto
- H5N1 adept pump to generate mightiness of motion
- Routes of carry
In higher animals, the medium is blood, the pump is the catch in addition to the road includes Artiness, veins in addition to capillaries
COMPONENTS OF BLOOD
Blood is composed of 2 major parts viz
· PLASMA
· CELLULAR COMPONETS
The liquid part of blood that constitute virtually 2/3 of the whole blood. It is a pale fluid amongst mimerous materials driveled unit. The contents include
- Water : About 90% of plasma is H2O
- Nutrient e.g Glucose, amino acids
- Vitamins
- Proteins e.g Fibrinogen, albumin in addition to globulins
- Harmones
- Dissolved gases e.g O2 , CO2
- Nitrogenous waste materials
- Electrolyte e.g Nacl, kcl etc.
- Enzymes
CELLS: The cellular components of blood include
1. Erythrocyte /RBC: These are biconcave (doughnut) /Disc-shaped modest cells that mensurate 7-10nm inward diameter in addition to 2 thick out side each ruby blood jail cellphone is produced inward the ruby os narrow in addition to has life bridge of 12o days (3months) they lack nucleus but posses a complex ruby paint called hemoglobin that binds amongst oxygen in addition to CO2 in addition to dominates on the concentration of each decreases.
Each molecule of hemoglobin binds amongst in addition to molecules of oxygen to cast oxy hemoglobin
Hgb + 4)2 ____ Hgb O8
About 5½ 1000000 ruby cells is introduce per mm3 of blood.
Function: They carry oxygen from the lungs to the tissues in addition to CO2 from the tissues to the lungs for purification.
2. LEUCOCYTES (WBC): There are amoeboid shaped cells that are modulated. They receive got variable life bridge in addition to mensurate 500-1000/mm3 inward number.
The displace through vessels in addition to tissues past times a procedure called Dipedesis. 2 groups of white blood cells are produced inward the Leucopenia procedure v12.
- Granulocytes
- Agranulocytes
Granulocytes include Polymorph Neutrophils. There receive got virtually 3-5 muchei jointed together past times a sparse Cytoplasmic
EOSNOPHILS: These cells absorb acids dyes in addition to receive got 2 muscle: they stain reddish inward hematoxylic stains
Banophuli: These cells stain bluish dark in addition to receive got 1-2 muscles: they are unremarkably involved inward allergy in addition to ingestion of poisons
Agranulocytes lack gramles but receive got nucleus they include
- Lymphocytes: 2 types of lymphocytes are hit inward the body. The ones produced inward the thymus gland are called T-lymphocytes. The i produced inward the blood are B-Lymphocytes they are involved inward the struggle against viruses in addition to bacteria.
- Monocytes: These are large generation cells amongst a horse-shoe nucleus. They undergo mitosis to give ascent to other cells. They also from component division of a defence scheme called macrophage or Reticent endothelial system.
FUNCTION:
White blood cells defend the trunk against infections diseases. They practise this past times a sample procedure called engulfing or phagocytosis. This is why volute blood cells cast a grouping of cells called phagocytes.
Platelets: These are small, irregular cells that are also celled thrombolytes. They are produced inward the os marrow in addition to incorporate a blood vessel constrictor called histamine. Platelets are involved inward a cascade blood article of apparel machinery that utilizes blood proteins to seal off cutting vessels these proteins are called clotting factors.
FUNCTIONS OF BLOOD
1. Transport of oxygen
2. Temperature rule that distribution
3. transportation of digested nutrient
4. Production of antibodies (WBC) past times WBS that struggle germs
5. Transport of excretory products
6. Transport of hormones
7. Transport of water
8. Defence of the trunk against illness causing organism – past times of clumping /Neutralization engulfing /clothing
9. Transportation of Co2
10. Blood clotting
BLOOD CLOTTING
To foreclose farther loss of blood when a blood vessel is damaged, the platelets copy a serial of medanism that finally seal the damages vessel.
These machinery are grouped into
a. Intense Mechanism
b. Extnsic Mechanism
These mechanisms are at converting fibrinogen to fibrin (a mesh piece of employment that tin terminate trap blood).
The procedure of blood clotting is outline insteps
Step 1: Platelets migrate to the damaged site in addition to chump together. They intermission opened upwards to release a neuromuscular constrictor called histamine. Histamine causes the blood vessels to narrow downwardly in addition to cut down blood flow.
Step 2: H5N1 heart in addition to soul thrombi kinas (an enzyme) is released past times the platelets. It catalyses the committee of prothrombin to thrombin.
Step 3: Thrombin combines amongst Ca2+ to covert fibrinogen to fibrin
Step 4: The fibrin traps in addition to block the damaged vessel along side amongst white blood cells. This is clotting sometimes, the clotting factors are absent inward individuals leading to excessive haemorrhage when vessels are damaged. This is a genetic status called Hemophilia. Other clotting factors include
Factor I Fibrinogen
II Prothrombin
III Tissue thromboplastin
IV Calcium Ion
V Proconvertin
VI Proaccelerin
VII Anti heaemophulic factor A
VIII Christmas factor
IX Stuart prower factor
X Antihaemoplulic factor
XI Hageman factor
XII Anti haemophulic factor C
MECHANISM OF TRANSPORT IN ANIMAL
Circulation refers to the continuous motion or flow of blood circular the trunk involving the catch in addition to the blood vessels. Circulation brings virtually the distribution of waste materials materials from trunk to the excretory organs.
Basically the circulatory scheme is of 2 principal types viz
- Open circulatory
- Closed circulatory
In opened upwards circulatory system, blood vessels Pb out of the catch chambers into trunk cavities called Haemocoels. In this bacmocols, the blood comes indirect contact amongst the cells in addition to tissues later on which it rectums to the heart. These type of scheme is an inefficient type equally blood is non separated inward them (oxygenated blood mix amongst deoxygenated blood). Each catch sleeping room has slits in addition to valves that allows blood to flow out alone inward i direction. The motion of muscles attached to the catch chambers aid to propel the blood.
The master copy component division of such a scheme is to carry nutrient in addition to waste materials products circular the body. Oxygen flow through a network of tubules called tracheal tubules hence blood inward this scheme has no paint so expression colorless.
In closed circulatory system, the blood is contained within vessels. These vessels include artery. Vein in addition to capillary blood flows out of the catch into large arteries. These arteries branch into modest ones called arteries. The arteries terminate inward ting unmarried layered vessels called capillaries. Capillaries serve equally an substitution point. It empties into ting venules which widen to cast veins equally shown.
Heart ______ Artery ____ Arteriole _____ Capillary ___ Venucle ____ Veins ____ heart. Here oxygenated blood is separated from deoxygenated blood. This is flora inward annelids, dishes, amphubians, Aves, Mammab etc.
CLOSED CIRCULATORY SYSTEM
Closed circulatory scheme allows either whatever of the 2 types of circulation viz
- Sing circulation
- Double Circulation
Single Circulation: In lower vertebrates similar fish in addition to amphibians, the catch chambers are incompletely separated into an atrium in addition to a ventricle. Blood from the full general circulation teach inward the atrium in addition to so the ventricle where it is pumped out to the gills. After oxygenation, the blood passes inward capillaries full general circulation. When this is done, the blood returns dorsum to the heart. This way that blood passes through the catch in i lawsuit every cycle. Valves guard the chambers to heighten blood flow inward management only. This type of circulation is real inefficient equally in that location is a mensuration of both oxygenated in addition to deoxygenated blood.
DOUBLE CIRCULATION
Higher animals sense double circulation. Here the blood passes twice through the catch inward equally consummate cycle. In Amphibians in addition to Reptiles, the illustration is non dissimilar fifty-fifty through they receive got an incompletely separated catch chambers. Oxygenated blood mixes partial inward them.
In mammal however, the oxygenated blood does non mix amongst deoxygenated blood. Blood passes twice inward 2 processes viz.
- Pulmonary Circulation
- Systemic circulation
In the minute stage of the cycle, blood is pumped out of the left ventricle past times the contraction of the muscular walls via the aorta to all organs of the trunk through diverse arteries. It finally returns to catch through the superior in addition to inferior vein cava.
These ready of contraction is militated past times a self generating conducting scheme of the heart. This scheme constitute
1. SA node (sim arteries node) / Pace maker
2. AV node (arteries ventricular node)
3. Bundle of His
4. Parking fitness.
LONGITUDINAL SECTION OF THE MAMMALIAN HEART.
The mammalian catch is divided into 4 chambers RA, RV, LA, LV. It located inward the mediation of the chest betwixt the 2 inward the mammalian lungs. The catch is covered exterior past times a tough connector tissue called Pencardium.
4 major vessels leave of absence or teach inward the catch viz
- Aorta
- The pulmonary arteng
- The pulmonary vein
- The vein cava
The hearts divided into the left in addition to correct cardia sides past times a sorption valves controls the flow of blood inward the heart.
Between the RA in addition to RV is the Trouped value
Between the LA in addition to LV is the mitral (bicuspid value)
The aortic value (semi hunar value guard the aorta)
The pulmonary value guard the pulmonary artery
The valves are strengthened past times tough chordate dentinal.
Blood flow through the catch is such that 02 blood flow into left side in addition to deoxygenated blood flow inward the right.
In a unmarried bicycle (heart cycle), blood which returns from the full general circulation via the vena cava leaves the pulmonary artery when the auricles contract at the same time oxygenated blood enters the left auricles inward the pulmonary vein.As the ventricles refill in addition to empty, a stronger contraction of the ventricular walls causes the semi inner values to opened upwards causing blood to leave of absence the aorta to the full general trunk circulation (systemic) these ready of contraction in addition to relaxation of the catch muscles causes the flapping of the valve cusps. It is called the catch beat.
The catch shell hence occure inward those 2 stages equally explain. The starting fourth dimension is to a greater extent than frequently than non known equally the Diastole (contraction of auricles)
The minute is the systole (Contraction of the ventricles)
These ready of activities happens in i lawsuit every 0.8 seconds amongst a piddling delay of 0.1 sec at each cycle.
The terminal pressure level inward the arteries of the trunk is left in addition to read equally pulse.
MAIN BLOOD VESSELS
The Corte is the largest artery that distributes scheme blood.
To the lungs – pulmonary arteries
- To the lungs _ pulmonary arteries
- To the forelimbs – Sectarian artery
- To the forelimbs is Hepatic artery
- To the intestine is the mesenteric artery
- To the kidney is the Renal
- To the limbs is the iliac arteries
- The catch is supplied by the coronary arties
The 1 is a collection of 2 3 and 4 that specializes in the most of materials from diverse component division of the trunk to other parts of the body. Complexity of scheme increases so that amoeba tin terminate displace materials circular the trunk past times uncomplicated processes similar 5 . This is because the Sa/V ratio 6 . Materials transported include 7 in plants from the leaves through the storage organs in addition to materials from the 8 to the liver through the 9 vain.
In amoeba, plants in addition to man, the medium of carry include 10 , 11 and 12 respectively. In higher organism a adept circulatory scheme must receive got a adept 13 equivalent to a fuel, a functioning 14 to generate the mightiness in addition to competent 15 as routes of transport.
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