Human nutrition

Question 1

what are the five processes of nutrition

Answer 1

Ingestion - The process of taking food, liquids or other substances into the body.

Digestion - Physical/mechanical and chemical breakdown of food into its simplest soluble form with the help of digestive enzymes.

Absorption - The products of digestion diffuse into the bloodstream.

Assimilation - Nutrients such as amino acids and glucose are incorporated into the cells and used to build new structures and compounds.

Egestion - The removal of undigested solid matter and unabsorbed water, during defecation, through the anus and in the form of faeces

Question 2

where are most digested molecules absorbed

Answer 2

Most digested molecules offood,as well aswater and minerals, are absorbed through the small intestine.

Question 3

what structures create a vast surface areathrough which nutrients can be absorbed.

Answer 3

Themucosaof the small intestine contains many folds that are covered withtinyfingerlike projectionscalledvilli. In turn, the villi are covered with microscopic projections calledmicrovilli.

Question 3

what structures create a vast surface areathrough which nutrients can be absorbed.

Answer 3

Themucosaof the small intestine contains many folds that are covered withtinyfingerlike projectionscalledvilli. In turn, the villi are covered with microscopic projections calledmicrovilli.

Question 4

what is assimilation

Answer 4

The process where nutrients are taken from the blood and moved into the cells

Question 5

what is the Hepatic Portal System

Answer 5

The alimentary canal is richly supplied with an extensive network ofcapillary blood vessels.Glucose, amino acids, vitamins, mineral salts and waterare absorbed through the blood capillaries in the villi.

The capillaries join to formvenules. The venules join with venules from the stomach to become thehepatic portal vein, which transports the absorbed nutrients to the liver. This system is known as thehepatic portal system.

In theliver,most of theglucose is converted to glycogen and storedin this form.

Excessamino acidsundergodeaminationto form urea and glucose.Theureais transported to the kidneys where it isexcretedas part ofurine.

The remaining glucose and amino acids leave the liver via the hepatic veins and are transported in theinferior vena cavato the heart and to the rest of the body.

In theheart, the blood isoxygenatedand then pumped to all parts of the body, distributing digested food molecules throughout the body.

Question 6

how the Hepatic Portal System works

Answer 6

1. When we eat food, it goes through our digestive system, where it gets broken down into smaller particles and nutrients like carbohydrates, proteins, and fats.
2. These nutrients are absorbed by the tiny blood vessels called capillaries located in the walls of our small intestine and stomach.
3. Instead of directly going into the general circulation, these nutrients and other substances are collected into a big blood vessel called the hepatic portal vein. Think of it as a special bus that collects all the nutrients and substances from the digestive system.
4. The hepatic portal vein then carries this nutrient-rich blood to the liver. The liver is like a central processing unit for our body. It performs various important functions like detoxification, storing nutrients, and producing important substances needed for our body.
5. Inside the liver, the blood from the hepatic portal vein gets filtered and processed. The liver checks the nutrients, removes harmful substances, and stores excess nutrients for later use.
6. After the liver has done its work, the blood leaves the liver through another blood vessel called the hepatic vein. This blood then rejoins the general circulation, and it can be transported to other parts of the body.

So, in summary, the hepatic portal system is a special pathway that carries nutrient-rich blood from our digestive system to the liver for processing, detoxification, and nutrient storage before it gets distributed to the rest of the body. It ensures that the liver can do its job effectively and helps maintain a healthy balance of nutrients in our body.

Question 7

what happens during assimilation

Answer 7

Absorbed nutrients are transported from theliver to the heartby the hepatic vein. From theheart,thenutrients moveto all parts of thebody.

A large proportion ofglucoseis transported to thetissues(especially muscle tissues), where it is broken down by cellular respiration into CO2and water with the release of energy.