Unit 8: Physiology of human body systems
Learning aim C: Explore the physiology of the digestive system and the use of
corrective treatments for dietary related diseases
Title: Nutrition and health
Introduction:
I will write a report explaining and comparing how a named dietary related
disorder affects the normal functioning of the digestive system. I am also going
to evaluate the impacts and effectiveness of treatments used to treat the
dietary disorder.
The roles and locations of organs involved in digestion
,The function of the digestive system is to digest and absorb. Digestion is the
breakdown of foods into smaller molecules which are absorbed in the body.
Chemical digestion occurs through the process of hydrolysis which uses water
and digestive enzymes to break down molecules. Digestive enzymes are used
to speed up the hydrolysis process.
Mouth – Secretes saliva from salivary glands, the saliva contains an enzyme
called amylase to break down starch from food into simple sugars. The mouth
also chews to break down food into smaller molecules that are easily
digestible. Secreting saliva is chemical digestion and chewing is mechanical
digestion.
Oesophagus – The oesophagus is an organ that connects the mouth to the
stomach and contracts in order to move food down to the stomach. The wave
like contractions are called peristalsis, it starts in the oesophagus and moves
balls of swallowed food to the stomach.
Stomach – The stomach is an organ that produces hydrochloric acid to kill
bacteria. The stomachs' main function is to store digested food where they are
broken down. The type of digestion is chemical digestion as enzymes are being
secreted to break down the foods. For instance, the release of pepsin into the
stomach is chemical digestion to break down proteins. Mechanical digestion
also happens in the stomach by peristaltic contractions of smooth muscle. This
further breaks down the food into smaller particles.
Liver – The liver is an organ that secretes bile into the small intestine to
emulsify/break down fats into fatty acids.
Pancreas – The pancreas is an organ that secretes pancreatic fluid into the
small intestine in order to neutralise the hydrochloric acid in the intestine.
Small intestine – The small intestine is an organ that absorbs nutrients of food
through villi into the bloodstream. This type of digestion is chemical digestion
as it requires the walls of the small intestine to make digestive juices/enzymes.
These enzymes include: amylase to break down starch into simple sugars,
lipase to break down lipids into fatty acids, and protease to break down
proteins into amino acids.
Large intestine – The large intestine is an organ that is responsible for the
reabsorption of water and mineral ions (sodium and chloride) from the
material that is not digested as food and get rid of waste products left. It
, connects and allows the material to travel to the rectum. The absorption of
water in the large intestine occurs through the process of osmosis, nutrients
such as sodium are absorbed by sodium channels.
Rectum – To store the material that has not been digested as food before it is
evacuated out of the body.
Anus – The opening at the lower end of the large intestine, it is where the
waste is evacuated in the form of faeces.
Mechanical and chemical digestion are the two methods used by the body to
break down foods. Mechanical digestion involves physical movements to make
food smaller. Chemical digestion involves using enzymes to break down foods.
For instance, and example of mechanical digestion is the movement of the
mouth (chewing) to break down food. An example of chemical digestion is the
secretion of saliva in the mouth to break down the starch from foods into
simple sugars using amylase.
Carry out investigations to establish sources and importance of key
nutrients for a balanced diet
Iodine test
1. Set up the foods to be tested (cracker, cereal, oil, and egg white).
2. Grind the cracker and cereal separately in a pestle and mortar.
3. Use a spatula for the solid food (cracker and cereal) and pipette to add
the liquid foods (oil and egg white) to the spotting tile.
4. Add 2-3 drops of iodine solution to each food.
5. Observe any colour changes, a positive result is a colour change to blue-
black.
Tile showing iodine solution on different foods
Learning aim C: Explore the physiology of the digestive system and the use of
corrective treatments for dietary related diseases
Title: Nutrition and health
Introduction:
I will write a report explaining and comparing how a named dietary related
disorder affects the normal functioning of the digestive system. I am also going
to evaluate the impacts and effectiveness of treatments used to treat the
dietary disorder.
The roles and locations of organs involved in digestion
,The function of the digestive system is to digest and absorb. Digestion is the
breakdown of foods into smaller molecules which are absorbed in the body.
Chemical digestion occurs through the process of hydrolysis which uses water
and digestive enzymes to break down molecules. Digestive enzymes are used
to speed up the hydrolysis process.
Mouth – Secretes saliva from salivary glands, the saliva contains an enzyme
called amylase to break down starch from food into simple sugars. The mouth
also chews to break down food into smaller molecules that are easily
digestible. Secreting saliva is chemical digestion and chewing is mechanical
digestion.
Oesophagus – The oesophagus is an organ that connects the mouth to the
stomach and contracts in order to move food down to the stomach. The wave
like contractions are called peristalsis, it starts in the oesophagus and moves
balls of swallowed food to the stomach.
Stomach – The stomach is an organ that produces hydrochloric acid to kill
bacteria. The stomachs' main function is to store digested food where they are
broken down. The type of digestion is chemical digestion as enzymes are being
secreted to break down the foods. For instance, the release of pepsin into the
stomach is chemical digestion to break down proteins. Mechanical digestion
also happens in the stomach by peristaltic contractions of smooth muscle. This
further breaks down the food into smaller particles.
Liver – The liver is an organ that secretes bile into the small intestine to
emulsify/break down fats into fatty acids.
Pancreas – The pancreas is an organ that secretes pancreatic fluid into the
small intestine in order to neutralise the hydrochloric acid in the intestine.
Small intestine – The small intestine is an organ that absorbs nutrients of food
through villi into the bloodstream. This type of digestion is chemical digestion
as it requires the walls of the small intestine to make digestive juices/enzymes.
These enzymes include: amylase to break down starch into simple sugars,
lipase to break down lipids into fatty acids, and protease to break down
proteins into amino acids.
Large intestine – The large intestine is an organ that is responsible for the
reabsorption of water and mineral ions (sodium and chloride) from the
material that is not digested as food and get rid of waste products left. It
, connects and allows the material to travel to the rectum. The absorption of
water in the large intestine occurs through the process of osmosis, nutrients
such as sodium are absorbed by sodium channels.
Rectum – To store the material that has not been digested as food before it is
evacuated out of the body.
Anus – The opening at the lower end of the large intestine, it is where the
waste is evacuated in the form of faeces.
Mechanical and chemical digestion are the two methods used by the body to
break down foods. Mechanical digestion involves physical movements to make
food smaller. Chemical digestion involves using enzymes to break down foods.
For instance, and example of mechanical digestion is the movement of the
mouth (chewing) to break down food. An example of chemical digestion is the
secretion of saliva in the mouth to break down the starch from foods into
simple sugars using amylase.
Carry out investigations to establish sources and importance of key
nutrients for a balanced diet
Iodine test
1. Set up the foods to be tested (cracker, cereal, oil, and egg white).
2. Grind the cracker and cereal separately in a pestle and mortar.
3. Use a spatula for the solid food (cracker and cereal) and pipette to add
the liquid foods (oil and egg white) to the spotting tile.
4. Add 2-3 drops of iodine solution to each food.
5. Observe any colour changes, a positive result is a colour change to blue-
black.
Tile showing iodine solution on different foods
