Digestion Flashcards
What is Digestion
Digestion is the breakdown of food into molecules that can be absorbed into the blood and dissolved into Plasma.
What are the two types of Digestion?
Mechanical and Chemical.
Where and how does Mechanical digestion occur within the Digestive system?
Mechanical digestion starts in the M0outh - where the teeth break the food down into smaller pieces, forming a bolus.
It continues in the Oesophagus where peristalsis is used to push the bolus into the stomach.
Most mechanical digestion occurs in the Stomach as it churns the food, turning into chyme. .
Where and how does Chemical digestion occur within the Digestive system?
Specialised (proteins) break large insoluble molecules of protein, carbohydrates and fats into smaller, soluble and easily absorbed molecules.
What makes Enzymes significant?
Enzymes are specific and need the right conditions (temperature and PH) to work efficiently.
What is Absorption?
This is when nutrients from digested food are absorbed into the blood.
Where does Absorption occur?
The digested food molecules are transported across the lining of the small intestine (ileum) into the blood.
Which Enzymes break down which food molecule?
Protease breaks down protein
Carbohydrase breaks down starch
Lipase breaks down fats
How is the Villi adapted to perform its function?
1) they contain microvilli which increase surface area.
2) they have an epithelium which is one cell thick so there is a short distance for absorption.
3) It has a goblet cell which produces mucus that protects the gut lining against digestion by the body’s own enzymes.
4) It contains capillaries which transports glucose and amino acids.
5) It has a lacteal which transports fatty acids and glycerol.
6) It has a circular muscle layer which is responsible for peristalsis.
What is Assimilation?
Assimilation is when food molecules are moved into the cells where they are used.
Where does Assimilation occur and what occurs?
Assimilation mainly occurs in the liver, and the liver sorts out digested food molecules and the nutrients are absorbed into the capillaries and sent to the rest of the body.
What is the main function of the Liver?
1) produces bile which helps in digesting fat.
2) It stores glucose as glycogen.
3) The liver converts amino acids into products important for the body by transamination.
4) The liver excretes excess amino acids in a process called deamination.
How does Chyme make enzymes access nutrients easier?
chyme increases the surface area for enzymes to access nutrients in the food easier.
