2006-2007 AP Biology

Animal NutritionHuman Digestion

Regents Biology

What do animals need to live? Animals make __________

using: __________________ __________________

Animals _______________ using: __________________

amino acids, sugars, fats, nucleotides

__________________

O2

food

ATP

__________________

Regents Biology

Different diets; different lives All animals eat other organisms

______________ eat mainly _________

gorillas, cows, rabbits, snails

______________ eat other __________

sharks, hawks, spiders, snakes

______________ eat ___________________

cockroaches, bears, raccoons, humans humans evolved as hunters, scavengers & gatherers

Regents Biology

Getting & Using Food ________________

taking in food

________________ __________________________

breaking up food into smaller pieces __________________________

breaking down food into molecules small enough to be absorbed into cells

enzymes

________________ absorb across cell membrane

___________________ ___________________

________________ undigested material passes out of body

intracellulardigestion

extracellulardigestion

Regents Biology

Digestive systemsEverybody’s got one!

Regents Biology

Mouth Functions

_______________________ _______________

break up food

_______________________ __________________________

____________________________ mucus

protects soft lining of digestive system lubricates food for easier swallowing

buffers neutralizes acid to prevent tooth decay

anti-bacterial chemicals kill bacteria that enter mouth with food

All thatin spit!

Regents Biology

Swallowing (& not choking)

________________________ flap of cartilage closes __________ (windpipe) when swallowing food travels down _______________

________________________ involuntary muscle contractions to move food along

Regents Biology

Stomach Functions

______________________ hydrochloric acid = pH 2

kills bacteria

______________________ can stretch to fit ~2L food

______________________ _____________________

What stops the stomach from digesting itself?

mucus secreted by stomach cells protects stomach lining

Regents Biology

Used to think ulcers were caused by stress

tried to control with antacids

Now know ulcers caused by bacterial infection of stomach

H. pylori bacteria now cure with

antibiotics

Ulcers

inflammation of stomach

inflammation of esophagus

Colonized by H. pylori

Free of H. pylori

white blood cells

cytokines

inflammatory proteins(CagA)

cell damaging proteins(VacA)

helper T cells

neutrophil cells

H. pylori

Regents Biology

Functions ______________________

_______________________ amylase from pancreas

_______________________ trypsin & chymotrypsin from pancreas

_______________________ bile from liver & lipase from pancreas

______________________ nutrients move into body cells by:

diffusionactive transport

Small intestine

This iswhere all thework is done!

Regents Biology

Absorption by Small Intestines ________________________________

finger-like projections _________________________________

SMALL INTESTINES6 meters long,but can stretch

to cover a tennis court

Regents Biology

Pancreas _______________________________

__________________________ trypsin, chymotrypsin

__________________________ amylase

__________________________ lipase

Buffers neutralizes

acid from stomach

smallintestine

pancreas

Regents Biology

Liver & Gall Bladder ________________________

_________________________________ _________________________________

that’s why you can have your gall bladder removed

bile contains colors from old red blood cells collected in liver =iron in RBC rusts & makes feces brown

bile contains colors from old red blood cells collected in liver =iron in RBC rusts & makes feces brown

Regents Biology

Large intestines (colon) Function

___________________________________ use ~9 liters of water every day

in digestive juices if don’t reabsorb water,

would die of dehydration

> 90% of water re-absorbednot enough water re-absorbed

____________________ can be fatal!

too much water re-absorbed ____________________

reabsorb by diffusion

Regents Biology

You’ve got company! Living in the large intestine is a

community of helpful bacteria Escherichia coli: ___________

____________________________ digests fruits & vegetables

____________________________ vitamin K & B vitamins

____________________________ by-product of bacterial metabolism methane, hydrogen sulfide STINKY!

PEE-YOO!

Regents Biology

Rectum Last section of large intestines

eliminate feces what’s left over?

___________________________ mainly cellulose from plants called ___________________________ keeps everything moving & cleans out

intestines

masses of bacteria

So don’t forget to wash

your hands!

Regents Biology

Different diets; different bodies Adaptations of herbivore vs. carnivore

teeth length of digestive system number & size of stomachs

Regents Biology

Teeth _______________

sharp ripping teeth

“canines” _______________

wide grinding teeth

molars _______________

both kinds of teeth

Regents Biology

Length of digestive system Herbivores &

omnivores long digestive

systems harder to digest

cellulose (cell walls) bacteria in intestines

help

Carnivores short digestive

systems

appendix

Regents Biology

Eating a balanced diet What happens if an animal’s diet is

missing an essential nutrient? deficiency diseases

scurvy — vitamin C (collagen production) rickets — vitamin D (calcium absorption) blindness — vitamin A (retinol production) anemia — vitamin B12 (coenzyme function)

kwashiorkor — protein

Regents Biology

Need to make sure you get enough protein 20 amino acids to make protein

12 humans can make 8 we have to eat = “essential amino acids”

Grains (like corn) have 6 amino acids missing 2

Beans (like soybean & red beans) have 6 amino acids missing different 2 mix beans & grains

for complete group of amino acids rice & beans taco/tortilla & beans tofu & rice peanut butter & bread

Vegetarian diets

Regents Biology

liver

______________

liver

Blood Sugar

blood sugar level

insulin

body cells takeup sugar

_________

liver stores _________

reduces ________

ucagon

______________

liver releases

_________triggers

_________

high

low

Feedback

Homeostasis