21.1-21.3 Flashcards
What are the three dietary categories?
Herbivores, carnivores and omnivores.
Define filter feeder.
Most aquatic animals which sift through the water for small animals/food particles. Other filter feeders ingest through their pores. Ex. Humpback whales have comb-like upper jaws which allow them to filter food out of water.
Define substrate feeder
organisms who live on their food source and eat their way through it. Ex. caterpillar.
Define fluid feeder
organisms that suck nutrient-rich liquids from a living host. Ex. mosquitos.
Define bulk feeders
ingest large pieces of food. Ex: humans
What is the most common type of feeder?
Bulk feeder
What diet category does a snowy owl fall under?
Carnivore bulk feeders.
What are the four stages of food processing?
Ingestion, digestion, absorption and elimination
Define ingestion
Mechanical digestion; or breaking food into smaller pieces so there is a larger surface area to be digested. Happens with teeth in bulk feeders.
Define the process of digestion.
Chemical breakdown by specific enzymes.
What is chemical digestion necessary?
Organisms cannot directly use the proteins, carbohydrates and lipids that enter their system. They need to metabolize them. They also would be too large to pass through the membrane of a cell.
During chemical digestion, what are the macromolecules split into?
Proteins–>amino acids Carbohydrates (poly/disaccharides)–> monosaccharides
Nucleic acids–> nucleotides
Fats –> glycerol and fatty acids
Define the process of absorption.
The cells lining the digestive tract absorb chemically digested material– amino acids and simple sugars. They then travel in the blood to either be broken down further or built up again.
What happens when an animal eats more than immediately needed?
Molecules are converted to fats.
Define the process of elimination.
undigested material is removed from the digestive tract.
What are two phases of digestion that take place in the human mouth.
Mechanical (ingestion) and chemical (digestion)
Define gastrovascular cavity
Found in animals with simpler body structure, it functions as the mouth to the anus of a digestive system.
Define alimentary canal
a digestive extending to two openings, a mouth at one end and an anus at another.
what is another word for throat
pharynx
What place stores and softens food
crop
What does a gizzard do
grinds and churns food
What are the advantages of an alimentary canal over a gastrovascular cavity?
An alimentary canal has specialized regions, which can carry out digestion and absorption sequentially.
