A&P Practical

Angiotensin II

constricting the blood vessels and hence increasing blood pressure Effects on the nerves (neurological), such as causing the sensation of thirst, desire for salt and encouraging release of anti-diuretic hormone from the pituitary gland and noradrenaline from sympathetic nerves Effects on the adrenal glands, such as stimulating aldosterone production resulting in the body retaining sodium and losing potassium from the kidneys Effects on the kidneys, such as increasing sodium retention and altering the way the kidney filters blood. This increases water reabsorption in the kidney to increase blood volume and blood pressure.

Enzymes and Hormones of the Pancreas

glucagon. This has the opposite effect to insulin, by helping release energy into the bloodstream from where it is stored, thus raising blood sugar levels.

Angiotensin I

it passes in the bloodstream through the lungs and kidneys, it is further metabolised to produce angiotensin II by the action of angiotensin-converting enzyme.

Pancreas

secretes digestive enzymes into the duodenum, the first segment of the small intestine. These enzymes break down protein, fats, and carbohydrates. The pancreas also makes insulin, secreting it directly into the bloodstream. Insulin is the chief hormone for metabolizing sugar.

Small Intestine

the duodenum, jejunum, and ileum — the small intestine is a 22-foot long muscular tube that breaks down food using enzymes released by the pancreas and bile from the liver. Peristalsis also is at work in this organ, moving food through and mixing it with digestive secretions from the pancreas and liver. The duodenum is largely responsible for the continuous breaking-down process, with the jejunum and ileum mainly responsible for absorption of nutrients into the bloodstream.

Angiotensinogen

Inactive protein made by liver, converted by renin into angiotensin I. A plasma protein that is a precursor to angiotensin II. Renin is used to convert this protein into angiotensin II.

Cause of Diabetes Milites

Insulin is a hormone produced by the beta cells of the islets of Langerhans in the pancreas in response to the intake of food. The role of insulin is to lower blood sugar (glucose) levels by allowing cells in the muscle, liver and fat to take up sugar from the bloodstream that has been absorbed from food and store it away as energy. In type 1 diabetes (or insulin-dependent diabetes mellitus), the insulin-producing cells are destroyed and the body is not able to produce any insulin. This means that sugar is not stored away but is constantly released from energy stores giving rise to high sugar levels in the blood. This in turn causes dehydration and thirst (because the high glucose 'spills over' into the urine and pulls water out of the body at the same time). To exacerbate the problem, because the body is not making insulin it 'thinks' that it is starving so does everything it can to release even more stores of energy into the bloodstream. So, if left untreated, patients become increasingly unwell, lose weight, and develop a condition called diabetic ketoacidosis, which is due to the excessive release of acidic energy stores and causes severe metabolic consequences. In 'type 2 diabetes' (accounting for 90% of all diabetes) the beta cells of the islets of Langerhans do not stop making insulin completely, but the insulin produced does not work properly so it struggles to store away the sugar found in the blood. As a consequence, the pancreas has to produce more insulin to compensate for this reduction in insulin function. This is termed as insulin resistance. Insulin resistance is linked to obesity. This type of diabetes is seen more commonly over the age of 40 years but can occur at any age.

Renin

Produced in the kidneys. An enzyme secreted by the juxtaglomerular cells when blood pressure decreases. Renin converts angiotensinogen to angiotensin I.

Large intestine (Colon)

Stool, or waste is passed through the colon by means of peristalsis. As stool passes through the colon, water is removed. Stool is stored in the sigmoid (S-shaped) colon until a "mass movement" The stool itself is mostly food debris and bacteria. These bacteria perform several useful functions, such as synthesizing various vitamins, processing waste products and food particles, and protecting against harmful bacteria. When the descending colon becomes full of stool, or feces, it empties its contents into the rectum to begin the process of elimination.

Gallbladder

The gallbladder stores and concentrates bile, and then releases it into the duodenum to help absorb and digest fats.

Liver

The liver has multiple functions, but its main function within the digestive system is to process the nutrients absorbed from the small intestine. Bile from the liver secreted into the small intestine also plays an important role in digesting fat. In addition, the liver is the body's chemical "factory." It takes the raw materials absorbed by the intestine and makes all the various chemicals the body needs to function. The liver also detoxifies potentially harmful chemicals. It breaks down and secretes many drugs.

Mouth

The mouth is the beginning of the digestive tract; and, in fact, digestion starts here when taking the first bite of food. Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use. Amalayze produced in the mouth to break down starches