Adaptations to Food Sources

Adaptations to Food Sources First, what do we get from the food we eat?

- Energy- Carbon- Nitrogen- Phosphorus - Other minerals and

vitamins

Adaptations to Food Sources All consumers eat something. What types of consumers do we have?

Mainly:Carnivores, Omnivores, and Herbivores

Different types of foods have different ratios of carbon to nitrogen (two main things we need to get from our diets)

Adaptations to Food Sources Carbon makes up more than 90% of all living matter, so most of what we eat is carbon

Plants contain 98% carbon and 2% nitrogen

Animals contain about 7% nitrogen and 93% carbon

Adaptations to Food Sources Herbivores- Have to deal with a food

source that has a lower amount of nitrogen, so they eat a much larger amount than a carnivore

- Another problem is that plants have chemical and physical defenses

Adaptations to Food Sources Plant Defenses- No defenses is perfect, most plants can defend against some but not all predators

Adaptations to Food Sources Plant DefensesPhysical Defenses - Thorns can either stop or slow down herbivores - Giraffe video- What do giraffes do?

Adaptations to Food Sources Plant DefensesPhysical Defenses - Grasses contain silica, which is what glass is made from - Herbivores that eat

grasses have specalized teeth, called high crowning teeth

- Ex: cow, elephant

Adaptations to Food Sources Plant DefensesPhysical Defenses- High crowning teeth are

capable of grinding tough plant tissues without wearing down as fast as low crowning teeth (like our molars)

Adaptations to Food Sources Plant DefensesPhysical Defenses- Cellulose is a molecule

found in plant cell walls- No vertebrae can digest

cellulose, so herbivores that eat grass have to use bacteria in their digestive tract to break it down.

Adaptations to Food Sources Plant DefensesPhysical Defenses: Cellulose - Many animals have a

cecum, which is a pouch that stores bacteria that breaks down food

Adaptations to Food Sources Plant DefensesPhysical Defenses: Cellulose - Mammals called

ruminants (cows, deer…) have a four-chambered stomach to help break down the grasses they eat

Elephant digestive system videoWrite 4 facts about the elephant’s digestive system:

Adaptations to Food Sources Plant DefensesPhysical Defenses: CelluloseRuminant’s 4 stomachs - The rumen

Food is broken down by

microorganisms into small balls of cudThe animal returns the cud to their mouth to be chewed on to crushthe fibers

Adaptations to Food Sources Plant DefensesPhysical Defenses: CelluloseRuminant’s 4 stomachs - The Reticulum + Omasum

Water, soluble food,and microbial productsare absorbed

Adaptations to Food Sources Plant DefensesPhysical Defenses: CelluloseRuminant’s 4 stomachs - The Abomasum

the “true” acid stomachwhere enzymes are secreted and “normal”digestion occurs