Absoprtion And Assimilation Flashcards
Define absorption
The end products of digestion being absorbed by the villi in the small intestine
What is the surface area of the small intestine so large?
- very long (6m)
- walls have transverse folds
- folds have projections called villi
What are characteristics of villi?
- epithelium tissue
- one cell thick
- richly supplied with mitochondria
- secrete mucus
- has microvilli
- rich supple of blood and lymph
- muscles causes swaying
How are fats absorbed?
1) Glycerol diffused into the villus
2) Fatty acids combine with bile salts to form water soluble complexes
3) Once in the villus, fatty acids recombine with glycerol to form fat droplets
4) The fat droplets enter the lacteal and together with glycerol form chyle
5) Fat passes through lymphatic system
How are CARBS and PROTEINS absorbed?
1) Carried using energy supplied by the mitochondria through the epithelial cells and into the blood of capillaries
2) Taken into the hepatic portal vein to the liver
How are absorbed nutrients transported?
1) Blood capillaries in the villi join to form the HPV
2) HPV carries rich blood to the liver
3) Blood with processed nutrients leaves the liver
4) HPV joins the inferior vena cava
5) Heart pumps nutrient rich blood to the body via the Aorta
Define assimilation
The using of nutrient molecules so they become part of the body
How is glucose assimilated?
- Used for the release of energy during respiration
- Excess glucose turned into glycogen and stored
How are amino acids assimilated?
Amino acids recombine by dehydration synthesis to form a variety of proteins (enzymes)
How does assimilation in the liver happen?
1) Converts excess glucose into insoluble glycogen
2) Revert glycogen to glucose when blood sugar levels low
3) Break down harmful toxins and hormones
4) Synthesises vitamin A from carotene
What is diabetes
High levels of glucose in the blood
What is type one diabetes?
- pancreas doesn’t secrete insulin
- born with it
- Beta cells don’t respond
How can someone treat type one diabetes
- daily insulin injections
- controlled diet
- exercise
What are common symptoms of diabetes.
1) increased thirst
2) frequent urination
3) exhaustion
