Do Now: After you eat your food, how does it get into the cells of your body?

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Do Now After you eat your food, how does it get
into the cells of your body?
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Digestion
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Aim What is digestion and how does it take
place in different organisms?
I. Digestion - The process by which food is
converted into substances that can be absorbed
and assimilated by the body.
A. Different types of digestion
1. Intracellular when food particles are broken
down within the cell.
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2. Extracellular when food particles are broken
down outside the cell. Usually involves
digestive enzymes.
3. Mechanical digestion when food is physically
broken down into smaller particles (increase the
surface area) so it can be digested easier.
4. Chemical digestion when food is broken down
and turned into a different substance by the use
of digestive enzymes. Example Starch is broken
down into disaccharides.
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B. Digestion in different organisms
1. One -cell (Unicellular) Organisms (ex Ameba,
paramecium)
Ameba
Paramecium
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a. Ingest food Ameba ingests (takes it into the
cell) food by the process of phagocytosis
(surrounds and engulfs food).
b. Food vacuole temporarily stores food until
it is digested by the lysosome which releases
digestive enzymes to break down food.
Intracellular Chemical Digestion!!!!!!!!!!!!!!!
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2. Digestion in the Hydra
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a. Paralyzes its prey with stinging cells located
in tentacles.
b. Ingests food through mouth
c. Both intracellular and extracellular digestion
occurs within the hydra.
d. Wastes are released through the mouth (2-way
digestive tract).
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3. Digestion in the Earthworm
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a. Ingests food through mouth
b. Food is temporarily stored in the crop
c. Food is mechanically broken down (grinded) by
the gizzard.
d. Nutrients are chemically digested and absorbed
in the intestine.
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i. Typhlosole fold in intestine that increases
surface area for both digestion and absorption.
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e. Anus where undigested material passes out of
Earthworm.
One way digestive tract!!!!!
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4. Digestion in the Grasshopper
a. Food is ingested through mouth and sucked
through the pharynx.
b. Food passes through esophagus.
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c. Food is mechanically broken down by mouth
parts (mandible)
d. Food is temporarily stored in the crop.
e. Has digestive glands (gastric caeca) outside
of intestine to help in chemical digestion.
f. Wastes temporarily stored in rectum and
eventually egested through anus.