Exam 4 Flashcards
What are the 4 steps for fueling bodies?
Ingestion -> Digestion -> Absorption -> Elimination
List the four feeding strategies.
Filter feeding
Substrate feeding
Fluid feeding
Bulk feeding
What is filter feeding?
when animals have specific structures in their mouths that strain food from their surroundings
Where do filter feeders usually live?
in aquatic environments
What is substrate feeding?
when animals live in or on their food
What is fluid feeding?
when animals pierce epidermis of others and suck nutrients in fluid form from a living host
What is bulk feeding?
when animals eat large pieces of food and must break it down to use nutrients
Why does all digestion happen extracellularly for animals?
Animal cells don’t have vacuoles.
What are the 2 kinds of places digestion can happen?
Gastrovascular cavity or alimentary canal (full digestive tract)
What is a gastrovascular cavity?
cavity where food is pulled in, digested, and nutrients are absorbed in the same compartment; single location for ingestion and excretion
happens with animals without a digestive tract
What is a digestive tract?
site of digestion organized into compartments for digestion, nutrient storage, and absorption; happens in animals with a mouth and anus
Where does the initial digestion of carbohydrates occur?
in the mouth
During the ingestion stage, what is responsible for chemical digestion?
Saliva. Amylase, specifically.
What is responsible for mechanical digestion?
chewing
Why is mechanical digestion helpful?
Chewing increases the surface area of food, increasing the rate of reactions.
What is saliva responsible for?
chemical digestion; protects mouth against abrasions; neutralizes acid; contains antimicrobial agents
What does amylase do?
hydrolyzes starch and glycogen
Where does food move from and to while being swallowed?
From mouth, down pharynx and esophagus, into stomach
Where does the digestion and storage of proteins take place initially?
stomach
