Digestion And Absorption Flashcards
What are the four types of digestive processes
- Mechanical
- Chemical
- Enzymatic (luminal and mucosal)
- Microbial
What does mechanical processing involve
- mastication (chewing)
- grinding action of the gizzard (birds)
- movement of the GI tract (segmentation and peristalsis)
What does chemical processing involve
HCl or gastric acid (pH 1.5-3.5)
What is involved in enzymatic digestive processing
What kind of enzymes are used
Digestive enzymes get secreted into the digestive tract
There are both luminal and mucosal enzymes
What is microbial digestive processing similar to (is)
It is also or similar to enzymatic digestion
Generally: what exactly is absorption
It is the ability for nutrients to move from the lumen to the blood stream by moving through the gut mucosal wall
What are the 2 main routes of absorption
- Transcellular (across cells)
- Paracellular (between cells)
What are the three transport mechanisms used in absorption
- Passive transport
- Active transport
- Osmosis (only for water)
—) uses aquaporins
What kinds of diffusion can be used in passive transport
- Facilitated diffusion
- Simple diffusion
- Osmosis (only for water)
Based on concentration where does water flow
It flows from low to high concentration
—) because it tries to even out the difference in concentration
What is the gradient called that influences the passive movement of substances
The electrochemical gradient
Where in the GIT is the most water absorbed
How is water absorbed (passive or active)
The small intestine
By passive transport (water can go through or between cells)
What happens to the majority of water in the body
Most of it is reabsorbed by the small intestine
What kind of bonds does cellulose have what kind of bonds does amylose have
Cellulose (beta bonds)
Amylose (alpha bonds)
What are the three kinds of monosaccharides
What are the three kinds of disaccharides (what is their make up)
Monosaccharides
- glucose
- fructose
- galactose
Disaccharides
- sucrose (glucose + fructose)
- maltose (glucose + glucose)
- lactose (glucose + galactose)
What kind of enzymes do bacteria have that allows them to cleave B bonds
Cellulolytic enzymes