Chapter 41- Animal Nutrition

Herbivores

Dine mainly on plants or algae

Carnivores

Mostly eat other animals

Omnivores

Regularly consume animals & plants or algae

Ingestion

Act of eating or feeding

Digestion

Process of breaking food down into molecules small enough to absorb

What is the order of the four stages of food processing?

Ingestion, digestion, absorption, elimination

Mechanical Digestion

Chewing or grinding, increases the surface area of food

Chemical Digestion

Splits food into small molecules that can pass through membranes

Absorption

Uptake of small molecules by body cells

Elimination

The passage of undigested material out of the digestive system

Gastrovascular Cavity

Animals with a simple body plan, functions in both digestion & distribution of nutrients

In which digestive system organ does nearly all nutrient absorption occur?

Small intestine

Alimentary Canal

A complete digestive tract

Oral Cavity

Where food processing begins

Salivary Glands deliver____

Saliva to lubricate food

Salivary Glands contain____

• Mucus, a viscous mixture of water, salts,
  cells, and glycoproteins

• Amylase, which breaks down starch

Pharynx (throat)

Junction that opens to both the esophagus & trachea

Peristalsis

Alternating waves of smooth muscle contraction & relaxation

Sphincters

Valves that regulate the movement of material between compartments

Stomach

Stores food and processes it into a liquid suspension

The Stomach secretes____ and mixes it with food through a churning action

Gastric Juice

Chyme

The mixture of ingested food & gastric juice

Pepsin

Breaks peptide bonds to cleave proteins into smaller polypeptides

The____ is the longest compartment of the alimentary canal

Small Intestine

The first portion of the small intestine is the

Duodenum

Pancreas

Produces the proteases trypsin & chymotrypsin, activated in the lumen of the duodenum

Bile

Consists of bile salts that facilitate digestion

Bile is made in the____ & stored & concentrated in the _____

Liver; Gallbladder

The jejunum & ileum region of the small intestine are for____

Nutrient Absorption

Jejunum & Ileum have large surface area due to_____

Villi & Microvilli

Hepatic Portal Vein

Carries nutrient-rich blood from the capillaries of the villi to the liver, then to the heart

Liver

Regulates nutrient distribution, interconverts many organic molecules, & detoxifies many organic molecules

Epithelial cells absorb fatty acids & a monoglyceride to recombine them into____

Triglycerides

Triglycerides get coated with phospholipids, cholesterol, & proteins to form water-soluble____

Chylomicrons

Chylomicrons are transported into a ____, a lymphatic vessel in each villus

Lacteal

Large intestine

Ends the alimentary canal

Cecum

• Aids in the fermentation of plant material & connects where the small & large intestines meet

• has an extension called the appendix, which plays a minor role in immunity

Colon

Completes the recovery of water that began in the small intestine

Rectum

Store feces until they can be eliminated through the anus

Microbiome

Collection of the microorganisms living in and on the body

The body stores energy not needed for metabolism
right away….

•  energy is stored first in the liver & muscle cells as____

• excess energy is stored in fat in____

Glycogen; Adipose cells

Glucose Homeostasis relies on the opposing effects of____

Insulin & Glucagon

The liver is the site for____

Glucose Homeostasis

Diabetes Mellitus

Deficiency of insulin or decreased response to insulin in target tissues

1. Type 1 Diabetes
• autoimmune disorder, immune system destroys the beta cells of the pancreas
• usually appears during childhood
• Treatment =insulin injections, typically several times per day
2. Type 2 Diabetes
• non-insulin-dependent failure of target cells to respond
• Excess body weight & lack of exercise significantly increase the risk
• appears after age 40, but may develop earlier in younger people who are
sedentary

Type 1 Diabetes

• Autoimmune disorder, immune system destroys the beta cells of the pancreas

• Usually appears during childhood

Type 2 Diabetes

• Non-insulin-dependent failure of target cells to respond

• Excess body weight & lack of exercise significantly increase the risk

• Appears after age 40, but may develop earlier in younger people who are sedentary