ANATOMY AND PHYSIOLOGY
P2, P3
4/27/2015
Khadra Ali |

P1 – Outline the functions of the main cell components
The human body is made up of millions of tiny cells that can only be seen under a microscope, cell also vary in shape and size. Cells are the basic structural of all living things. The human body is poised of trillions of cells. They give structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. Cells also contain the body’s hereditary material and can make copies of them. Cells all have different sizes, shapes, and jobs to do. Each cell has a different function. The actual definition of cells is the smallest structural unit of the body that is capable of independent functioning, it consisting of one or more nuclei; it has a cytoplasm, and various organelles which are all surrounded by a cell membrane.
There are four main parts to a cell; Plasma/Cell membrane, Cytoplasm, Nucleus and Cell Organelles.
Plasma/Cell membrane:
The plasma/cell membrane is a phospho-lipid-protein bi-layer; the lipids are small fatty molecules in two layers (bi-layer) with larger protein molecules inserted at intervals partly or completely through the bi-layer. The lipid molecules are phospholipids, the two lipid chains are insoluble in water and the phosphate head is water soluble. The fluid which surrounds the cells and the cytoplasm are watery environments next to the phosphate heads. Protein molecules create channels throughout the membrane to allow substances pass to and from the cell, they also act as identity markers for molecules such as hormones. This structure is also known as the ‘fluid mosaic model’ of the cell membrane.
Cytoplasm:
Cytoplasm is a semi-fluid, similar to a gel consistency which the capability to move slowly, there are various chemical reactions which occur here, the term for these reactions is metabolism. The cytoplasm is a complex storage of sugars such as glucose and melanin. Melanin is the dark pigment responsible for their skin and hair colour. (Uk.ask.com, (2014).
Nucleus:
The nucleus is as dark shape and is normally the largest structure inside the cell; it takes up the dyes and strains easily. Most cells have a single, central, spherical nucleus but there are many variations. Muscle cells have many nuclei so they are called ‘multinucleate’; some red blood cells lose their nucleus during development which is called ‘anucleate’ and some white blood cells have distant lobed nuclei.
The nuclear membrane is similar to the cell membrane but contains gaps or pores to allow protein and nucleic acids pass. When the cell is not dividing, the appearance will be thick, tangled massed which his called chromatin network. A small dark sphere is often visible; this is the source of ribonucleic acid (RNA) which is one of the nucleic acids. The nucleus controls nearly all the activities of the cell and it has been linked to the architectural drawing or blueprint from which the cell operates.
Chromosomes:
Chromosomes are peg-shaped structures located in the nucleus of a cell which contain genetic information. Humans have 23 pairs of chromosomes (i.e. 46 chromosomes altogether).
Cell organelles:
Organelles are different components of a cell with a distinct structure and their own functions and can be likened to miniature organs. Organelles include; mitochondria, the endoplasmic reticulum, the Golgi apparatus and lysosomes.
Mitochondria:
Every cell in the body has at least 1000 spherical bodies, rod-shaped and very energy-active cells will have many more. Each mitochondrion has a double-layered membrane like the cell membrane, however the inner layer is folder which produces ‘shelves’ which are known as cristae, this is where the end stages of glucose oxidation are located. The energy that has been released is stored until required by a ‘chemical battery’ called adenosine triphosphate.
Endoplasmic reticulum:
‘Endo’ means with in and reticulum is a complex word meaning network. There are two variations to endoplasmic reticulum (ER) which are rough and smooth. The ER is a branching network which fills the cell interior; the channels are similar to the cell membrane they create passageways for transporting materials to and from different parts of the cell. Rough ER is studded with tiny black bodies known as ribosomes; they make cell protein and act as a temporary storage area. Smooth ER has no attached ribosomes and is involved in the metabolism of lipids or fats. (Studios, A. (2014).
Golgi apparatus:
This is a series of flattened, fluid-filled sacs stacked like pancakes. The Golgi apparatus is believed to package proteins for delivery to other organelles; it is also responsible for producing lysosomes.
Lysosomes:
Lysosomes can be found in all parts of the cell cytoplasm, they are also small vesicles produced by the Golgi apparatus. As these are capable of digesting all major chemical components of living cells they are also called suicide bags. They are free to travel throughout the cell; they destroy damage or old organelles, even entire cells. They are also able to destroy bacteria and other foreign materials such as carbon particles. Some white blood cells such as; phagocytes, monocytes and tissue cells known as macrophages are loaded with lysosomes as there function is to destroy bacteria, viruses and foreign materials.

P2- Outline the structure of the main tissues of the body.
Introduction
In this Assignment I will be outlining the structure of the main tissues of the body. The main tissues of the body that I will be focusing on are the epithelial tissues, connective tissues, muscle tissues and the nervous tissues.
Epithelial Tissues
Simple Squamous Epithelial has thin and flat cells which on one side permit them to have a large surface area which is open to the lumen on one side (the apical surface) and to the basement membrane on the other side. The structure of the epithelial tissues is the epithelial tissue covering the entire surface of the body and it is also made up of cells closely filled and stretched in one or more layers. The purpose of the tissue is to form a protection or lining of all internal and external body surfaces. The function of the simple squamous epithelial tissue is to allow easy transmembrane association across the membrane and towards the cell of small molecules. Whereas other molecules such as oxygen and carbon dioxide are drawn-out freely across the simple squamous epithelia. (Botany.uwc.ac.za, (2014).
Simple Cuboidal Epithelium cells are unevenly square or they can be found as cuboidal in shape. Each cell includes a spherical nucleus in the centre. Cuboidal epithelium is established in glands and in the lining of the kidney tubules along with the tubes of the glands. They also create the germinal epithelium which creates the egg cells in the female ovary and the sperm cells in the male testes. (Bio.davidson.edu, (2014).
Simple Columnar epithelial take place in one or more layers. The cells are extended and column-shaped. The nuclei are elongated and are found located near the base of the cells. Columnar epithelium practices the lining of the stomach and intestines. Some columnar cells are specific for sensory reception like in the nose, ears and the taste buds of the tongue. Unicellular glands are set up in the middle of the columnar epithelial cells of the duodenum. (Bio.davidson.edu, (2014).
Compound Epithelia is to protect deeper structures and multiple layers of cells hamper the passage of resources. The vagina, mouth, tongue and oesophagus are ruled by the stratified epithelia which involves of layers of squamous, cuboidal or columnar cells which usually become crushed.
Connective Tissues
Connective tissues function to support the body and connect together all types of tissues maintaining the form of the body and the organs providing cohesion and internal support. This tissue includes several types of fibrous tissue that are rare only in their density and cellularity. (Biologyreference.com, (2014).
Blood
The blood contains the straw coloured plasma where many different types of blood cells are carried. In the plasma different elements are passed on to dissolved gasses like oxygen and carbon dioxide. The role of the plasma is blood clotting, transport and fighting against invading bacteria. White blood cells are known as Granulocytes and are known for fighting against infections protecting the body. The blood is circulated around the body through the blood vessels by the pumping action of the heart. The function of the blood is to supply oxygen to tissues and supply nutrients like glucose and amino acids getting rid of waste like carbon dioxide.
Cartilage is one of the forms of the connective cells where the cartilage called chondrocytes secures the small lacunae within the matrix. Cartilage expands with the development of additional matrix and incorporation of new cells. The job of the cartilage is to protect bone ends from friction during movement and puts together the main part of the nose and the external ear flaps called the pinnae.
The bone is seen to be tougher that the cartilage but if friction takes place it can be worn away. There are two components of the rigid matrix these are the calcium salts that come together around the collagen fibres giving the bone firmness. The aim of the bone is to provide protection for our important but weaker tissues like the brain, lungs and the heart.
Areolar tissue – the Areolar tissue is made up of sticky white material that binds muscle groups and blood vessels bringing the nerves together. The matrix consists of collagen fibres and elastic fibres concealed with cells that are found in the loose connective tissue. The aim of the elastic fibre is to provide flexibility to the tissue that is found around the mobile structures.
Adipose tissue - the adipose tissue is another word for the fatty tissue this is because the tissue cells have been multiplied to obscure the other cells and fibres. The adipose tissue helps to protect the body against sudden extreme changes of temperature and absorbs shock to prevent injury.
Muscle Tissue
Muscles are tissues that react to stimuli however in the human body there are 3 different types of muscles that are called the striated muscle, the non-striated muscle and the cardiac. All the muscles are collected of muscle fibres that are in control of shortening and going back into their original state. (Ivyroses.com, (2014).
Striated muscle
The function of tissue is to allow the body to move by constant contraction and relaxation with the responsibility of sustaining posture and stabilising the joints and producing heat through the muscle function. The muscle is also responsible for mobility in the body and limbs this is because the muscle is attached mainly to the bones and skin.
Non-striated muscle
The smooth muscle fibres are small and tapered, each smooth muscle fibre has a single centrally located nucleus. This muscle is linked to the digestive system where the action of smooth muscle helps to move food along the gastrointestinal tract where the food is broken down more. Also contributing to move the fluids through the body, the smooth muscle is located in the stomach or linked to blood vessels and the intestines.
Cardiac muscle fibres are striated and branched also has a single central nucleus. The fibres of the cardiac muscle are attached at the end of the adjoining fibres by the intercalated discs also called the thick plasma. The cardiac muscle pumps blood through the heart de-oxygenates blood through the right atrium and the left atrium. (Ivyroses.com, (2014).
Nervous Tissue
In the nervous system the only tissue found is the nerve tissue where it is linked to the brain, spinal cord and nerves of the body. In the nervous system there is something called the sense organs that stimuli is interpreted too this is so that vision, hearing, smell and other senses can become obvious.
Neurones – are nerve cells that transfer nervous impulses they are also only existent in the spinal cord and the brain where the long processes from the nerves. There are different types of neurones such as the motor neurones, sensory neurones and relay neurones. This cell transmits electrical nerve impulses from one part of the body to another, carrying information.
Neuroglia- the connective tissues cells are combined with the neurones in the brain and spinal cord this is so that they can offer care and defence.

P3 – Outline the gross structure of all the main body systems.
The Renal System
The renal system consists of the kidneys, ureters, urinary bladder and urethra. The ureters, urinary bladder, and urethra all work together to form the urinary tract, which behaves as a plumbing system to release urine from the kidneys, store it, and then release it during urination. The kidneys remove waste from the body and produce urine.
The renal system is made up of two kidneys which sit next to each other near the pelvis. From both kidneys a long tube called the ureter takes urine from the renal pelvis in the kidneys to the bladder to be stored. From the bladder the urine leaves the body through a single tube called the urethra. The regulation of this leaving the bladder is by the contraction and relaxation of sphincter muscles. The kidneys are supplied with oxygen from the aorta which splits into renal arteries and the waste products such as carbon dioxide are removed by the renal veins which join into the vena cava. (Stanfordchildrens.org, 2015)
The skin, the liver, and the kidneys synthesize calcitrol which is the active form of Vitamin D.
Some of the diseases you can get from the urinary system is firstly UTI’s (Urinary Tact Infections), this occurs when bacteria enters the urinary tact and then effects the urethra, the bladder or possibly even the kidneys. This type of disease is more common in men than women. Another example of a disease is prostatitis; this is a swelling of the prostate gland which means that this disease can only occur in men. One more example may be getting kidney stones; this is a illness that can happen to men and/or women. Kidney stones are clumps of Calcium oxalate which is found in the urinary tact. In addition, this certain illness can cause back and side pains as well as blood in the urine. (Stanfordchildrens.org, 2015)

The Nervous System
The nervous system consists of many things, such as, the brain, spinal cord, sensory organs and all of the other nerves which connect these organs with the rest of the body. The nervous system consists of 2 parts, central and peripheral.
Brain - The brain is made up of billions of neurons, it helps the body respond to the information it receives from the senses. A bundle of nerve fibres called the corpus callosum pass signals back and forth from the left and right side. (LiveScience.com, (2014).
Spinal Cord - The spinal cord is a tube of neurons which runs up the spine and attaches to the brain stem.
Sensory neurons reacts to a stimulus, so in this instance, light, sound, and touch, and then it send feedback to the central nervous system about the body’s surrounding environment. The response for this is automatic. This system also allows reflexes to occur - a reflex is a muscle reaction that happens inevitably. Motor neurons are located in the central nervous system; these transmit signals to activate muscles or glands. Glial cells hold all the neurons in place, these also provide nutrients to neurons, remove dead neurons, kill pathogens, and can also act as traffic cops by directing the axons of neurons to their targets. (LiveScience.com, (2014).
The gross structure of the nervous system is split into the central nervous system which is made up on the brain and spinal cord and the peripheral nervous system which is made of all nerves which go either to or from the brain or spinal cord. Receptors in the skin detect changes to the environment and neurones pass impulses to relay neurones in the spinal cord. These then create an impulse in motor neurones which take the impulse to an effector e.g. a muscle which creates a change. (LiveScience.com, (2014).

The Endocrine System
The endocrine system plays a role in regulating mood, growth and development, tissue function, metabolism, and sexual function and reproductive processes. The major glands are the hypothalamus, pituitary gland, thyroid, parathyroid, adrenal glands, pineal body, reproductive glands and the pancreas. (LiveScience.com, (2014).
The gross structure of this system is a collection of ductless glands found all around the body. The different glands have different jobs as they produce different hormones. However, all of them secrete these hormones into the blood so they can be transported to the site they act at. This means these glands are always close to blood vessels. (LiveScience.com, (2014).
The pituitary gland is known as ‘the master gland’. This gland produces many hormones and also has the ability to control other glands. This gland is divided into two sections which differ both, structurally and functionally. However, there are also disorders/diseases that can be caused by the pituitary gland. The most common cause is prolonged hyper secretion of GH (growth hormone); this is usually caused by a hormone-secreting pituitary tumour. This usually only occurs due to excess growth hormone releasing hormone which is secreted by hypothalamus. In addition, if the size of the tumour does increase, it can lead to damage of the optic nerves which can cause visual disturbances, and secondly, hypo secretion of other pituitary hormones of the anterior and posterior lobes.

The Lymphatic System & Immune System
The lymphatic system is a part of the circulatory system and has many functions, such as the removal of interstitial fluid, the extracellular fluid that bathes most tissue. Also, it acts as a highway, and transports white blood cells back and forth the lymph nodes into the bones, and antigen-presenting cells to the lymph nodes. (LiveScience.com, (2014).
This system is made up of blind ending capillaries which lie in tissue spaces between the body cells and join up into larger lymphatic vessels and eventually into two lymphatic ducts called the thoracic and right lymphatic ducts. These ducts transfer fluid collected in the lymphatic vessels back into the blood circulation. Each lymphatic vessel passes through lymph nodes where white blood cells can check for pathogens and destroy them. Other lymphatic tissues are found in the body such as the tonsils, spleen, thymus gland and adenoids. In the small intestine are lacteal, small lymphatic vessels which are where fat absorption occurs.
The spleen contains white blood cells which fight infections or disease. It is also the largest lymphatic organ in the human body that is placed on the left side of the body, under the ribs and above the stomach. In addition, the spleen can also help control the amount of blood in the body and also dispose any old and damaged blood cells. (LiveScience.com, (2014).
The bone marrow is the yellow tissue in the centre of bones which produce white blood cells. This certain type of tissue contains stem cells (immature cells).
Lymphocytes play a role in defending the human body against disease. There are two types of lymphocytes, these are B-cells and T-cells; B-cells are what make antibodies which attack the bacteria and toxins, whereas T-cells help destroy infected and cancerous cells. (LiveScience.com, (2014).
The thymus is a small organ where T-cells mature. The thymus is large in infants; grown up until puberty then shrinks and is replaced by fat as everyone becomes older.
Leukocytes are disease fighting white blood cells that identify and get rid of pathogens, and these also are the second arm of the immune system.

The Reproductive System
There are four main functions to the reproductive system; to produce hormones, to nurture the developing offspring, to transport and sustain these cells and also to produce eggs and sperm cells.
For the male system the sperm is produced in two testes which hang from the body is skin sacs called the scrotum. They hang below to body to keep them cool. Each testes is connected to a tube called the vas deferens which take the sperm to the urethra which runs down the inside of the penis. Seminal vesicles and the prostate gland, both which sit near to the bladder, add fluid to the sperm in the vas deferens to produce the ejaculate. At the prostate gland is where the vas deferens becomes the urethra. The penis is made of erectile tissue which surrounds the urethra that fill with blood. (System, 2015)
For the female system it is made up of two ovaries, each connected to a fallopian tube. When the egg is released from the ovary it travels down the fallopian tube to the uterus. This is where a foetus develops. The base of the uterus has a small gap called the cervix which links the uterus to the vagina. The cervix has circular muscles which can expand during childbirth. The vagina is where the penis enters and sperm is released during sexual intercourse.
For the male system the sperm is produced in two testes which hang from the body is skin sacs called the scrotum. They hang below to body to keep them cool. Each testes is connected to a tube called the vas deferens which take the sperm to the urethra which runs down the inside of the penis. Seminal vesicles and the prostate gland, both which sit near to the bladder, add fluid to the sperm in the vas deferens to produce the ejaculate. At the prostate gland is where the vas deferens becomes the urethra. The penis is made of erectile tissue which surrounds the urethra that fill with blood. (System, 2015)

The Musculo-skeletal System
There are 4 main functions of the Musculo-skeletal system; movement, protection, support and blood protection. The skeletal system includes the bones of the skeleton and the cartilages, ligaments, and other connective tissue that stabilize or connect the bones. (Ptdirect.com, 2015)
Gross structure
Made up on the skeleton and skeletal muscles of the body which are attached to the body. The skeleton is split into the axial skeleton, which includes the skull and spine and the appendicular skeleton which includes all the limb bones.
Bones are linked by joints which may be:
Fibrous – joints which are immoveable e.g. in the skull
Cartilaginous – can move slightly as has a pad of cartilage e.g. between vertebrae
Synovial – move in all directions e.g. shoulders
Muscles attached to the bones attach by tendons and pull bones into different positions by contracting or relaxing. Muscles on opposite sides of a bone do opposite actions.
Some of the diseases that can be caused by the musculoskeletal system are:
Arthritis: this is where as we get older, our joint tissues become less resilient to wear and tear and start to degenerate manifesting as swelling, pain, and oftentimes, loss of mobility of joints. A more serious form of disease is called rheumatoid arthritis. (Ptdirect.com, 2015)
Carpal Tunnel Syndrome: for those who have jobs such as painting, typing etc, may develop a pain in their thumb, index and middle fingers which may lead to the movements of the thumb becoming weak especially when grabbing an object. Repetitive flexing movements may inflame and thicken the ligament over the “tunnel” through the carpal (wrist) bones trapping and compressing the nerve. (Ptdirect.com, 2015)

The Immune System
The immune system is made up of cells, tissues and organs which work together to protect the body. The function of the immune system is to protect the body from invasion by microorganisms. The structure of the immune system is that it’s made up of many things, such as the tonsils, thymus gland, spleen, adenoids, lymphatic vessels & lymph nodes, and the white blood cells (lymphocytes, granulocytes and monocytes). (Kenny, 2015)
This system is closely related to the lymphatic system and is scattered throughout the body. Major parts of the system include white blood cells which circulate in the blood and lymphatic systems, the thymus tissue where T cells mature and bone marrow (where stem cells can make new white blood cells to replace old ones). White blood cells (lymphocytes) called phagocytes which circulate in the blood engulf and destroy foreign substances. B lymphocytes produce antibodies which bind to specific pathogens and signal for their destruction. (Kenny, 2015)
The lymphatic system is a network of tissues and organs that primarily consists of lymph vessels, lymph nodes and lymph. The tonsils, adenoids, spleen and thymus are all part of this very system. A function of the lymphatic system is to transport lymph; this is a colourless fluid containing white blood cells that helps rid the body of toxins, waste and other unwanted materials. They lymphatic system has a number of functions, this includes the removal of interstitial fluid; this is the extracellular fluid that bathes most tissue. It also transports white blood cells to and from the lymph nodes into the bones. (Kenny, 2015)

The Cardiovascular system
The cardiovascular system consists of the heart, the blood vessels and also blood. This specific system’s role is to transport oxygen, nutrients, hormones and waste products throughout the body. There are 3 main functions that the cardiovascular system does; transport, regulates and protects; these are the roles that the cardiovascular system carries. (LiveScience.com, (2014).
Transport - this system transports substances; oxygen, nutrients, hormones and waste products throughout the body.
Protect - it protects the body via white blood cells, antibodies, and complement proteins which circulate in the blood and defend the body against microbes and toxins.
Regulation - The cardiovascular system regulates the body temperature, if it was to rise too high then the blood vessels near the skin increase in size. If the body temperature was to decrease, the blood vessels would decrease in size. The smaller surface area of blood vessels next to the skin causes less heat to be lost across the skin and keeps more heat in the body. (LiveScience.com, (2014).
The cardiovascular system gross structure is made up of the heart and the associated blood vessel. The heart is split into four chambers, two atrium and two ventricles. The left side of the heart takes oxygenated blood and the right deoxygenated. The chambers are separated by atrioventricular valves to stop blood going back where the cardiac muscle contracts. Veins carry the deoxygenated blood (except the pulmonary vein) and the arteries carry oxygenated blood (except the pulmonary artery). Capillaries go into tissues and organs and are where materials are exchanged. The veins take blood to the lungs to be oxygenated. The arteries take blood to all parts of the body before returning to the heart to be pumped to the lungs.

The Respiratory System
The respiratory system is made up of the organs in the body, as respiration means breathing. The aim of breathing is to deliver oxygen to the body and to take away carbon dioxide. The respiratory system gives oxygen to the body’s cells while removing carbon dioxide. There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration.
The airways includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body’s exterior. The lungs pass oxygen into the body and remove carbon dioxide out of the body. The muscles of respiration work together to behave as a pump, pushing air into and out of the lungs whilst breathing. (System, 2015)
Gross Structure
The mouth and oral cavity take air into the body and down the trachea; a tube which contains C shaped cartilage to stop it collapsing. The trachea splits into two bronchi which takes air to each lung in the chest cavity. Each of these splits further into tiny bronchioles which take air into tiny sacs called alveoli where gas exchange occurs into capillaries which surround them. Intercostal muscles between the ribs make them move up and out to help inflate the lungs and a sheet of thin muscle below the lungs called the diaphragm contracts to move down to help inflate the lungs. When these relax the lungs deflate and we breathe out. (System, 2015)

The Digestive System
Mouth-
At the start of the digestive system comes in the mouth; this is because when you are taking your first bite of food this is when the digestion takes place from chewing your food allowing the food to mix with the saliva this is so the food then is broken into small pieces which allow the body to digest the food more quickly and easily letting the human body to absorb and use the food with nutrients and supplying the body with energy. (System, 2015)

Oesophagus-
The oesophagus is found in your throat near the trachea which is also known as the windpipe, what oesophagus does is collects food from the mouth this is done when eating food, after a number of muscular contractions which are known as the peristalsis, the oesophagus then starts to deliver food to the stomach this is so it can provide the body with nutrients and energy. (Webmd.com, 2015)
Stomach-
The stomach is an organ which contains three different layers that have muscles with in it. In the stomach there are different types of enzymes that are in the process of breaking down the food into a functional form, this is so the ring of muscles that are called pyloric sphincter start to discharge the mixture of food that is churned into the small intestines. Within the stomach there is one enzyme that is called pepsin this enzyme is in control for the protein breakdown of food. In the stomach there is also acid which is known as hydrochloric acid, this acid is then used to kill and reduce any bacteria that could be found in the food that is consumed, the main function of the stomach is to break down the food and then release it into enzymes and acids this is because the food is then broken down further chemically. The widest part of the stomach is the alimentary canal this where the food can be stored in the stomach for up to 3 hours however food that contains protein takes longer whereas food not containing protein is passed through very quickly. (System, 2015)
Liver and gall bladder
The Gallbladder is estimated to be the size of a pear shaped organ which is found one the underside of the liver this is where it is used to store bile. The gallbladder is an organ that has small storage and is located lower but next to the liver. Even though the gallbladder is small in size, it still plays an important role in the digestion of food. The bile that is produced in the liver is held by the gallbladder this is until the digestion of fatty foods takes place in the duodenum of the small intestine. If the bile in the gallbladder starts to crystallize and forms gallstones, this can become painful and possibly life threatening. In our body the liver is the largest organ this organ weighs about 1.4kg once the human body individual is grown. The liver has two lobes that are on the left and right, except the right lobe is slightly bigger than the left lobe. The liver is found on the right hand side of the abdominal cavity underneath and behind the ribs. There are many different functions of the liver but the main three functions are makes and stores fuel, which clean the blood and make bile that travels from the liver into the small intestine.
Pancreas
The pancreas hides digestive enzymes into the duodenum; the duodenum is first part of the small intestine. The enzymes break down protein, fats, and carbohydrates, the pancreas also makes insulin stashing it straight into the bloodstream. Insulin is known to be the chief hormone for metabolizing sugar.
Small intestine /Ileum
The small intestines are an organ which is used to be part of the digestive system this organ is found in the abdomen of a human body. The organ is estimated to be about five meters long, when the food is chewed in the mouth and is swallowed down the oesophagus it is then entered into the stomach which is then transfers the swallowed food into the small intestine. When the swallowed food is passed through the wall of the small intestine and into the bloodstream, the digested food molecules are then passed around the body to where they are needed. It is found to be soluble substances that can only pass across the wall of the small intestine. When the food is digested it is absorbed into the small intestine and passed through into the bloodstream therefore the inside wall of the intestines which is known as the villi where absorption takes places quickly. The villi also contain blood capillaries to take away the absorbed food molecules. (Webmd.com, 2015)
Large Intestines
The large intestine is a 6-foot long muscular tube which connects to the small intestine into the rectum. The large intestine is prepared up of the cecum which is the right colon, the across colon, the left colon, and the sigmoid colon, all these colons connects to the rectum. A small tube attached to the cecum is called the appendix and the large intestine is also a highly exported organ which is responsible for processing the waste so that the bowels are emptied is easily and more conveniently.
Rectum/Anus
The size of the rectum is an 8-inch chamber which links the colon in the anus. The aim of rectum is to collect stool from the colon, this then informs the human body that there is stool to be removed, and to keep hold of the stool until it is removed from the body. When gas or stool enters the rectum, the sensors put out a message to the brain, this then informs the brain leaving it to decide if the rectal substances can be released or not. If they the rectal substances can be released the sphincters then start to relax enabling the rectum to contract, the contents are then if there is difficulty in the contents not being disposed, the sphincter contracts and the rectum accommodates so that the sensation is reduced in the short term. (Webmd.com, 2015)
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