The digestive system

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Diet and Digestion



Day 1

Breakfast – Scrambled Egg on Toast

Brunch – Feta Salad and chocolate bar

Lunch – Chicken and Rice

Snack – Tuna Sandwich and crisps

Dinner- Steak and Vegtables

Day 2

Breakfast – Porridge with fruit

Snack – Milkshake and packet of crisps

Lunch- Poached egg on toast

Snack-Wholegrain Bar

Dinner-Chicken and Pasta

Day 3

Breakfast – Weetabix

Snack – Cous Cous and Ham and ice cream

Lunch – Beef Sandwich

Snack – Two peices of fruit and crisps

Dinner – Pork chops and potatoes

Pregnant Women

Day 1

Breakfast – Weetabix

Snack – Two peices of fruit and chocolate bar

Lunch – Cheese omlette

Snack-Yoghurt with fruit

Dinner- Chicken and Vegtables

Snack – Banana Split

Day 2

Breakfast – Fried egg on toast

Snack – Chocolate Apple

Lunch- Cheese and Salad Sandwich

Snack – Yoghurt with Nuts and Raisins

Tea – Spaghetti Bolognese

Snack - Apples

Day 3

Breakfast – Grilled English Breakfast

Snack – Pear and milkshake

Lunch – Jacket Potato with Tuna

Snack – Banana

Dinner- Chicken Dinner

Snack – Fruit Meringue

Elderly Male

Day 1

Breakfast - Porridge

Lunch- Rivita with cream cheese

Snack – A peice of fruit

Dinner – Chicken and Vegtables

Day 2

Breakfast – Toast with Marmalade

Snack – Yoghurt

Lunch – Jacket Potato with Cheesey Beans

Snack - Tangerine

Dinner – Chilli con carne and rice

Day 3

Breakfast – Weetabix

Snack – Dried fruit and nut with Milkshake

Lunch – Ham salad sandwich

Snack – Crab sticks

Dinner – Shepherds Pie

TAQ 2 B)

The reason I have chose this three day menu for an athlete is because it is high in protein and high in calories. An athlete needs a healthy diet to support peak performance. Athletes have higher needs for calories than the average individual and need to stay well hydrated, especially during intense physical activities. A healthy diet should follow dietary guidelines and include a variety of foods to meet daily requirements for essential vitamins, minerals and nutrients. I have chose crisps, chocolate bars and ice cream as part of the athletes snacks as athletes tend to use around 1000 calories more than an average person per day. Athletes do need more fats that the average person as they burn these off daily and the fats supply a good source of energy for them.

I have chose this three day menu for a women in her third trimester of pregnancy as it is high in protein and calcium. Protein is an important building stone of human cells and given the rapid cell development of your baby-to-be. Drinking milkshakes and eating yoghurts will provide a good source a calcium for both mother and baby to be. Calcium is extremely important for maintaining healthy bone growth for the baby to be. I have at least 5 portions of fruit and vegetables on each day as these provide essential vitamins and minerals like Vitamins A,B,B1,C,D,E,iron, potassium, sodium, zinc and folate. I have also allowed three meals aswell as three snacks throughout each day. The reason for this is because the mother is feeding for not only herself but also for the baby to be so will need a bigger calorie intake.

The reason I have chose this three day menu for an elderly male in hospital is because it provides all essential minerals, vitamins, proteins and fats. An elderly male in hospital does not need the same amount of calories as an active elderly male. An elderly male in hospital will only need 2000 calories not the 2500+ a male will usually have. Osteoporosis is very common in elderly people so a high source of calcium is a must. I have included yoghurts, milkshakes and cream cheese at least once a day in this menu so that the male will receive a good amount of calcium into his system. After we reach 50, recommended nutrient intake drops by 5 percent for each decade we age due to a decrease in the body’s active cells and loss of muscle tissue. This diet provides enough calories that provides all the right nutrients needed for an elderly male in hospital.


  1. Type 2 Diabetes - When the pancreas does not create sufficient insulin to maintain a normal blood glucose level or your body cannot use the insulin produced Type 2 Diabetes occurs. Cells don’t respond properly because the insulin receptors on their membranes don’t work properly, so the cells don’t take up enough glucose. This means the blood glucose concentration is higher than it should be. The insulin that is produced within the body is used to control glucose levels in the blood. This glucose is then converted to energy. An inadequate diet can cause Type 2 Diabetes and obesity is often linked to it. Consuming a high calorie/sugar diet and drinking alcohol strengthens the chance of developing the disease. If you are overweight this places an additional pressure on your body such as the ability to maintain proper blood glucose levels. Being overweight can also cause your body to become resistant to insulin. Simply losing weight and controlling how much you eat can be done to treat Type 2 Diabetes. If this does not work glucose-lowering tablets may be used.
  2. Atherosclerosis – Atherosclerosis is also known as arteriosclerotic vascular disease. This condition is where the arteries have become hardened and narrowed due to an excessive build up of plaque around the wall of the artery. In arteries they contain endothelium. Endothelium is a thin layer of cells, this keeps the artery smooth allowing blood to flow easily. When the endothelium is damaged this allows cholesterol to accumulate within the artery wall causing atherosclerosis. The entire artery tree can be affected by this but usually happens in the larger high pressure arteries. Causes of atherosclerosis include smoking, high blood pressure, high levels of cholesterol and high levels of sugar in the blood. Having an inadequate diet and consuming foods with a high calorie and high sugar content will contribute greatly to attaining atherosclerosis. Allowing foods like this to enter the body will heighten the risk of cholesterol and plaque build up inside the artery, consequently creating blood clots from blood cell fragments called thrombocytes sticking together. Lifestyle changes can often be a treatment for atherosclerosis such as weight management, eating a healthy diet and regular exercise. Medication can also be prescribed to assist and in extreme cases surgery may be carried out to treat blockages.
  3. Rickets – Rickets is a nutritional disorder caused by a deficiency of vitamin D, phosphate or calcium. Rickets cause the softening of bones potentially causing fractures and deformity. The majority of cases of rickets usually occur in children especially in developing countries however adults can also suffer. Vitamin D is essential for maintaining bone health. Not eating the right foods that contain vitamin D such as eggs, fish oils, mushrooms, margarine, fortified milks and juices may lead to a vitamin D deficiency consequently causing rickets. Malnutrition is a big factor in why rickets occur and this is why it is more common in third world countries where severe droughts and starvation occur. Blood tests, bone biopsies and x-rays can be used to diagnose this disease. Complications of rickets can be seizures, cramps and breathing problems caused by the severely low blood calcium levels within the body. Heart muscle weakness can also be caused by rickets and the increased likelihood of fractures to the bones which can result in permanent deformity. Treatment of rickets is exposing the individual to more sunlight, prescribed medications and eating a high vitamin D enriched diet.


  1. The digestion is important in terms of absorption and assimilation of nutrients for a number of reasons. Food needs to be prepared, digested and broken down into very small molecules from larger molecules. After this process the food molecules can they be absorbed efficiently into the blood. Bodies spend a lot of time breaking food down we eat thus using a lot of energy. Chewing our food more before we swallow would help with the process of absorption and assimilation. If there is a concentration gradient, the absorption into the intestinal walls will work more effectively. However, if the epithelial lining were permeable to glucose molecules the process would be slow and wasteful.

Organ/ Body Part



Mouth/ Buccal Cavity

The process of the mouth is to chew the food into small pieces before swallowing.

The importance of this process of chewing is to break the food down small enough to allow enzymes to act more effectively on a larger surface area.


The oesophagus pushes food down into the stomach by its muscle walls contracting. Food can also be brought up the oesophagus in the same way when a person vomits.

The importance of the oesophagus is to transport the food that the mouth has chewed right down to the stomach for the next stage of processing.


The stomach produces gastric juice which breaks down food. The stomachs muscles which creates a churning action physically breaks down the food. The stomach then releases food into the small intestine.

The stomach is important because its the site in which all food is broken down into its primary components so it can be absorbed later on in the digestive system.

Small Intestine

The small intestine is where chemical digestion of food takes place aswell as the absorption of nutrients into the blood.

The small intestine is 5 metres long and because of its large surface area it serves well for maximum absorption of the nutrients.

Large Intestine

The large intestine is where water, salts and minerals are absorbed. The large intestine also gets rid of waste product that has been left.

The large intestine is important as its the final step before excretion. It makes sure all waste and toxins are deposited here for excretion aswell as the final absorption of key minerals, waters and salts.


The anus is the last stop in the digestive system. The anus is where faecal matter and all other waste is disposed of out of the body.

The importance of the anus is to excrete all the waste in the body to stop toxins poisoning the body and causing complications.


Name of Digestive Juice

Site of Production

Enzymes in Digestive Juice

Functions of the enzymes

Gastric Juice

The gastric juice’s site of production is inside the stomach.

The enzymes in the digestive juice is pepsin.

The enzyme of pepsin is produced in the mucosal lining of the stomach. This enzyme hydrolises proteins into smaller peptide chains and only works in acidic conditions. The main function of this enzyme is to break down the proteins that are found in food such as eggs and meat into small peices called peptides. The peptides are then broken down into monomers called amino acids which contain carbon, hydrogen, oxygen and nitrogen.

Pancreatic Juice

The pancreatic juice is found within the pancreas.

The enzymes in this juice is amylase, trypsin, chymo trypsin, lipase and carboxypeptidase.

The trypsin, chymo trypsin and carboxypeptidase are proteases and catalyse the hydrolysis of proteins. The amylase is a carbohydrase and catalyses the hydrolysis of carbohydrase. Lipase catalyses the hydrolysis of lipids into fatty acids and glycerol. The pancreatic juice is used in the duodendum which is part of the small intestine.

Salivia Juice

The site of production for the saliva is in the salivary glands in the mouth.

The enzymes in saliva is amylase.

The salivary amylase breaks down starch into maltose which is a disaccharide. Starch is a mixture of two polysaccharides of alpha-glucose. These are amylase and amylopectin. The maltose can then be hydrolised into glucose by maltase which is released by the intestinal epithelium.

TAQ 4.




3.Ascending colon

4.Large Intestine




8. Stomach


10.Tranverse Colon

11.Small Intestine

12.Descending Colon



Digestive System Organ



Digestion begins in the mouth. Chewing breaks food up into smaller pieces whilst saliva mixes with the food to begin the process of breaking down into a form the body can absorb and use.


Livers main function is to process the nutrients absorbed from small intestine.

Ascending Colon

This carries faeces from the cecum superiorly along the right side of our abdominal cavity to the transverse colon. Also, the bacteria digests the faecal matter in order to release vitamins.

Large Intestine

The main function of the large intestine is to transport the waste and reabsorb the water and vitamins before it is excreted. The large intestine also represents the end of the digestive tract. Also, the large intestine produces anti-bodies that helps with immunity.


There are no known functions of the appendix.


The anus is the final stage in the digestive tract. The anus is used to dispose of any waste products in the body. The waste is known as faecal matter.


The oesophagus has one main function and that is to transport food, saliva and liquids from the mouth to the stomach.


The stomach is located on the left side of the upper abdomen. The main function of the stomach is to break down and digest food. It does this by storing food then breaking it down.


The pancreas has two functions. The pancreas breaks down fats, carbohydrates and proteins into energy for the cells in the body aswell as regulating blood sugar. It does this through the secretion of hormones.

Transverse Colon

The transverse colon is the most flexible and longest part of the colon. Its function is too retrieve water from waste and to absorb vitamins like vitamin B and K which are produced by the intestinal flora.

Small Intestine

The function of the small intestine is where the absorption of the food nutrients takes place and it also breaks them down into liquid form. This is the main part of where digestion takes place.

Descending Colon

The descending colons function is to make sure the absorption of water is completely free of faecal matter.


The function of the rectum is to store the faecal matter until it is ready to be moved on to the anus of excretion. The rectum keeps the small intestine closed.


Three main layers of the gut wall are found in the stomach, the small intestine and the large intestine. The stomach is a small sack containing lots of folds allowing it to expand. The stomachs main function is to temporarily store food while its muscular churning mixes the food. There is an outer muscle layer protected by a thin coating of fibres, a middle layer this is called the submucosa and finally an inner layer called mucosa. The stomach wall produces gastric juice which helps break down the food. The layers relax and contract which in turn creates an effective churning action. The submucosa seperates the muscular and glandular layers, while the mucosa layer is thick with deep pits. These deep pits contain glands that secretes acid, mucus and enzymes. The stomach produces hydrochloric acid which also kills microorganisms which might of been ingested. Peristalsas of the stomach turns food into an acidic fluid called chyme. The chyme is then moved into the small intestine which is made up of two parts which is called duodenum and the ileum. The duodenum contains bile and pancreatic juice which neutralise the acidity of the chyme and break it down into smaller molecules. In the ileum the smaller molecules are absorbed by the gut wall that is covered in millions of villi. These villi provide a huge surface area so the molecules can be absorbed by diffusion, facilitated diffusion and active transport. Next the large intestine or colon absorbed minerals, salts and water. The large intestine is a muscular tube about two metres long. The large intestine has a huge surface area due to its folded wall providing optimum area for absorption.