Monday, January 14, 2008

Jan. 10

Here are some key points we should have absorbed today

Animals get thier food by
-
Filter (suspension) feeding
-Substrate feeding
-Fluid feeding
-Bulk feeding

-Animals cannot make: elements; N, P, K, Fe, Na, Ca and NAD, FAD so they must take it in through food

peristalsis-push food along by rhythmic waves of smooth muscle contraction in walls of the digestive system.

Sphincters-muscular ring-like valves, regulate the passage of material between sections of digestive system.

Accessory glands- salivary glands, pancreas, liver, and gall bladder secrete digestive juices such as enzymes and fluid.

Stomach-stores foos, disinfects food, performs chemical digestion

Ulcers-caused by a bacteria overload in your stomach called helicobacter pylori cured with antibiotics.

Small intestine-chemical digestion, absorption through lining
-duodenum=most digestion
-jejunum=absorption of nutrients and water
-ileum=absorption of nutrients and water

-the small intestine is lined with villi and microvilli
the villi increase the surface area to absorb materials into the blood

large iontestine-re-absorb water
the large intestine is inhabited by countless bacteria including E. coli
the bacteria produce necessary vitamins for survival and help with digestion

Rectum-eliminate feces (extracellular waste) this waste has never been absorbed into the bloodstream.

1 comment:

Samantha McAllister said...

Thanks for the summary on the immune system! I have to read Survival of the Sickest for my AP Bio class and and this really helped. http://www.harpercollins.ca/authors/30553/Dr_Sharon_Moalem/index.aspx