Digestion Flashcards
(20 cards)
What is heterotropical feeding?
When the human or animal does not produce their own food but feeds on an autotroph
What is digestion?
Digestion converts large insoluble particles into small, soluble molecules.
What are the 2 types of digestion?
- Chemical digestion
2. Mechanical digestion
What are the 5 stages of digestion?
- Indigestion
- Digestion
- Absorption
- Assimilation
- Egestion
What is Indigestion?
The act of taking food into the mouth
What is the first step of indigestion?
- Mechanical digestion.
The teeth grind and crush the food into smaller pieces to increase surface area
What is the 2nd step of indigestion?
Chemical digestion through the saliva.
What components of the saliva assists in indigestion?
- Water- dissolves soluble parts of food.
- Mucus- lubricates food for easier movement through the alimentary canal.
- Salivary amylase- digests starch.
- The tongue- helps to churn food and rolls it into a bolus at the back of the throat to be swallowed.
What are the steps of digestion in the mouth?
- Indigestion
- Chewing
- Lubrication
- Starch digestion through amylase enzymes to form maltose.( slightly alkaline)
What is the oesophagus?
A muscular tube connecting the mouth and stomach
How is the oesophagus adapted to its function?
It uses peristalsis (a wave of muscular contractions which moves downwards to squeeze food into the stomach)
What is the stomach?
An elastic and muscular sack with spincter muscles at its end.
What is the function of the spincter muscle?
To control and regulate the flow of food into the stomach
Explain the mechanical digestion of the stomach
The walls of the stomach contract and relax churning the food
What are the 3 chemicals of the stomach?
Hydrochloric acid
Mucus
Renin and pepsin enzymes
Where are the 3 chemicals of the stomach produced?
The gastric juice from the gastric glands in the gastric pits produce HCL and renin and pepsin.
The goblet cells produce mucus
Does protein digestion occur in the stomach? Explain if yes.
Yes! Protein molecules are broken down by pepsin to leave polypeptides.
What are the functions of the HCL in the stomach?
- kills pathogens and bacteria
2. creates an acid environment for enzyme activity.
What are the functions of the renin in the stomach?
Curdles mother’s milk into proteins which are then digested into polypeptides by pepsin.
How long does food spend in the stomach?
Where does it go after ?
- 1-2 hours in the stomach
