Animal Nutrition and Digestive System

Herbivores

animal’s food is plant-based

ex. mule deer, koalas, crickets, caterpillars

Frugivores

fruit-eaters

Granivores

seed eaters

Nectivores

nectar feeders

Folivores

leaf eaters

Carnivores

“meat eater”

ex. lions, tigers, snakes, sharks, sea stars, spiders, ladybugs

Obligate carnivores

rely entirely on animal flesh.

ex. lions & cheetahs

Facultative carnivores

also eat non-animal food in addition to animal food

Omnivores

eat both plant- and animalderived food.

ex. Humans, bears, chicken, cockroaches, crayfish

Gastrovascular cavity

Alimentary Canal

Invertebrate Digestive System

Gastrovascular cavity

organisms with only one opening for digestion

ex. flatworms, comb jellies, coral, jelly fish, sea anemones.

Alimentary Canal

tube with a mouth at one end and an anus at the other ex. earthworm

Monogastric Digestive System

Avian Digestive System

Ruminants

Pseudo-ruminants

Vertebrate Digestive System

Monogastric Digestive System

one stomach chamber ex. Humans and rabbit

Avian Digestive System

Birds do not have teeth have 2 stomach chambers: proventriculus, gizzard

gizzard

food is stored, soaked, and mechanically ground.

proventriculus

gastric juices are produced

Ruminants

mainly herbivores eats roughage or fiber ex. cows, sheep, and goats

4 compartments of stomach: 1. rumen 2. reticulum 3. omasum 4. abomasum (true stomach). *contain microbes

Pseudo-ruminants

ex. camels and alpacas

3 stomach chamber: 1. reticulum 2. omasum 3. abomasum

Cecum

large, where the roughage is fermented and digested

joins the ileum to the colon.

Oral Cavity (mouth)

Esophagus

Stomach

Small Intestine

Large intestine

Rectum and Anus

Parts of the Digestive System

Oral Cavity (mouth)

point of entry of foodchemical

digestion begins in the ___

mastication (chewing)

food consumed is broken into smaller particles

salivary glands

produces saliva

parotid

submandibular

sublingual

3 major glands that secrete saliva:

Mucus

Immunoglobulins and lysozymes

Salivary amylase

Lipase

Components of saliva:

Mucus

moisten food and buffers the pH.

Immunoglobulins and lysozymes

antibacterial action

Salivary amylase

converts starch to disaccharide (maltose).

Lipase

enzymes that can breakdown triglycerides.

bolus

The chewing and wetting action provided by teeth and saliva prepare the food into a mass called the __

pharynx

bolus will move from mouth into __

trachea

opening called the glottis covered by epiglottis

Esophagus

leads to the stomach. tubular organ connects the mouth to the stomach

peristalsis

a wave like movements of esophagus

gastro-esophageal sphincter

located at the stomach end of the esophagus.

Stomach

saclike organ secretes gastric digestive juices

pH level: between 1.5 and 2.5 (highly acidic)

can expand to up to 20 times.

Major site for protein digestion in animals other than ruminants.

pepsin

chief cell > pepsinogen(inactive form) + hydrochloric acid =

chyme

digested food and gastric juice

enzyme pepsin is synthesized in the inactive form

stomach has a thick mucus lining

2 ways the stomach lining is protected:

Small Intestine

long tube-like organ; highly folded surface containing villi; microvilli 6m long Divided into three parts: Duodenum, Jejunum, and Ileum

Duodenum

separated by the pyloric sphincter

Bile

produced in the liver and stored in the gallbladder.

Jejunum

Hydrolysis of nutrients

Large intestine

Reabsorbs the water

Processes the waste material

Cecum

Colon

Rectum

3 parts of the large intestine:

Colon

divided into four regions (ascending colon, transverse colon, descending colon, and the sigmoid colon). *extract the water & mineral salts

Rectum

end of the large intestine store feces

Anus

exit point for the waste material

inner and outer sphincter

Two sphincters that control elimination:

Liver

Pancreas

Gallbladder

Accessory Organs

Liver

Largest internal organ

produces bile

Digestion fats and detoxification of blood.

Pancreas

chyme

Digests protein and carbohydrates

Gallbladder

stores bile

Digests fatty acids

Carbohydrates

Proteins

Fats

Vitamins

Minerals

Organic Precursors

Carbohydrates

organic carbons in the animal body.

Polysaccharides → glucose Cellulose → glucose

Proteins

catabolism provides organic nitrogen

Amino acids - building blocks of ___.

Excess nitrogen is toxic.

Amino acids

building blocks of proteins.

Fats

source of energy

aid absorption of fat-soluble vitamins and the production of fat-soluble hormones.

Vitamins

essential organic molecules

Minerals

Inorganic essential nutrients

crop

Chicken’s Digestive System

The chicken doesn’t have a teeth so it has 2 stomach to process the food. Food is picked up by the beak and swallowed, then stored in the ____, where it softens.

proventriculus (2)

Chicken’s Digestive System

It moves to the ___, which adds digestive juices

gizzard (2)

Chicken’s Digestive System

and then to the ____, a strong, muscular part that grinds the food using small stones the chicken swallows.

cloaca

Chicken’s Digestive System

Finally, the leftover waste passes through the large intestine and leaves the body through the ____.