Digestive System Flashcards
What is an autotroph?
An organism that can convert abiotic sources of energy into energy stored in organic compounds (during photosynthesis)
What is a heterotroph?
An organism that cannot produce its own food, takes nutrition from other sources like plant and animal matter
What is the alimentary canal?
The gut (long tube which is continuous with the body’s exterior)
What do all cells require to live?
Chemical energy
Where does digestion take place?
The gut
How can food molecules be absorbed?
Food consumed by heterotrophs must be digested first
What happens in the mouth
Food enters alimentary canal in mouth.
Teeth cut food for easy digestion
Saliva moistens food making it easy to swallow
What does saliva contain and what is it?
Contains enzymes which digest the starch in the mouth
Which organ comes after the mouth?
The tongue pushes food to the back of the throat into the oesophagus.
It’s then pushed into the stomach by peristalsis
What is peristalsis?
movement of the faeces or bolus along the intestines (relaxing and contracting)
What happens in the stomach?
Food is churned and mixed with gastric juices (enzymes in the juice digest protein)
Where does the food go after the stomach?
To the small intestine, completing digestion.
Bile is released into small intestines to break down large bits of fat so it can digest easier.
Pancreatic juice also helps with digestion
What do the large intestines do?
Absorbs water from material that enters.
Fibre in the materials helps to absorb water keeping materials moist and moving.
Where is the undigested food stored?
Stored in the rectum and released through the anus
