Mod 3 Digestion, Absorption & Metabolism Flashcards
(24 cards)
what is the role of enzymes?
they speed up the rate of reactions
What is hydrolysis
the input of water helps to break down a molecule
-for example, sucrase is a sugar that when a hydrolysis reaction occurs it splits into smaller molecules glucose and Fructose
Condensation reactions
the process of condensation reactions binds amino acids together, water is liberated in the process!
Gastric Lipase
breaks down lipids
Pepsinogen
Becomes pepsin when it comes in contact with Hydrochloric acid, which breaks down proteins
hydrochloric acid -HCL
unravels proteins, and turns pepsinogen into pepsin
Nutrient subunits enter the villi of the small intestine where they can be absorbed and enter the ___ or the ___
the BLOOD or the LYMPH
These enter the lymph by passive diffusion
Lipids, fat soluble vitamins
This enters the villi by facilitated diffusion (protein transporter required)
Fructose
This enters the villi by Active transport, protein transporter required
Glucose, amino acids
“Accessory structures” to the digestive tract
liver, gallbladder, pancreas
Pancreatic juice contains 4 things (3 are enxymes)
1- bicarbonate (neutralize the acidity of chyme)
2- Lipase
3- Amylase
4- Proteases
What is the function of bile ?
Bile is a lipid emulsifier- is allows lipids to be moved around in a watery environment. Bile’s hydrophobic tails arrange themselves around the lipids and their hydrophilic heads face out at the watery environment of the lumen (sm intestine)
What is the a structure of lipids encased in bile called?
A Micelle !
in the LARGE intestine, unabsorbed material is either (2):
1-packaged up for removal 2-acted on by bacteria (the microbiota; microbiome )
The microbiota have a role in
- energy synthesis
- vitamin absorption
- health and disease (a lot we don’t yet understand)
Prebiotics
carbohydrates that act as food for the microbiota
Probiotics
cultures of living organisms- bacteria (like in yogurt)
All nutrients absorbed by the villi head to the liver EXCEPT
lipids and fat soluble vitamins
Anabolism
smaller molecules come together to form larger ones
–> requires an INPUT of energy
Canabolism
larger molecules are broken down into smaller ones
–>results in an an output of energy
—–“a net release of energy”
This is the energy captured by the body within ATP
Cellular respiration
the catabolism of energy -yielding nutrients leading to the production of ATP
Glycolysis is….
the break down of glucose (anerobic, produces minimal ATP)
Ketogenesis
can occur in a very low carb and high fat diet- the citric acid cycle requires carbohydrates -on low carb diet fatty acids cannot enter the citric acid cycle- but instead form KETONES
