Feeding and Digestion Respiration Circulation Excretion Animal Systems Feeding and Digestion Respiration Circulation Excretion

Feeding and digestion How does digestion occur? How are mouthparts adapted for different diets?

Ways of obtaining food Filter Feeders- Catch algae and small animals by using modified gills, or other structures as a net to filter food items out of the water. Ex. Sponges, Barnacles, Whales Detrivores- Feed off of decaying organic matter. Ex. Earthworms Carnivores- Consuming other living organisms. Ex. Whales, Spiders, Lions Herbivores- Consuming plants, or parts of trees for energy. Ex. Birds, Sea Slug Parasitism- Dependence on another animal for energy Ex. Flatworms, Roundworms

Processing Food A digestive tract has two openings, one to ingest food, and one to expel wastes. Digestion begins in the mouth. Mechanical Digestion How are carnivores teeth different from herbivores? Chemical Digestion In humans we start breaking down complex sugars in the mouth, using salivary amylase

Digestion Carnivores typically have short digestive tracts that produce fast acting meat digesting enzymes No animal produces digestive enzymes that are able to break down the cellulose in plant tissues Herbivores have very long intestines with specialized pouches, some containing symbiotic bacteria that digest cellulose Ex. Cows, have an extension in their esophagus called a Rumen, it regurgitates food that has been digested there, where the animal chews it again and re-swallows it. “chewing the cud”

Human Digestive System Why do we need to eat? What nutrients does your body need? What is a balanced diet?

Energy Food contains energy our body needs to carry out its functions Laboratories measure the calories (energy) found in food by heating it up A calorie (lower case c) is the amount of energy needed to raise the temperature of water by 1 degree Celsius A dietary Calorie is equal to 1000 “calories”

Nutrients There are about 45 substances found in food that your body does not make itself, therefore we need to consume it somehow. Water, the body needs water to carry out cell processes, it makes up most of your blood, and extracellular fluid. Water is lost even when we breath On hot days we need to drink more fluids than normally to replace those lost through sweat.

Carbohydrates Found in many things you wouldn’t think Carbs are in the sugars found in fruits, grains, potatoes, milk

Fats Usually people associate fat in their diet as a bad thing, but we actually need it If you don’t get enough you may not be able to absorb some essential vitamins found in foods Organs wouldn’t be insulated

Proteins Supply minerals for growth and repair

Digestion in the small intestine Most of digestion occurs here Chyme mixes with chemicals which are excreted by the Pancreas, Liver and Gallbladder Pancreas Regulates blood sugar levels Produces enzymes to break down carbs, proteins, lipids, and Nucleic Acids Produces Sodium Bicarbonate…Why? Liver and Gallbladder Aids in fat digestion Liver produces bile, then stores it in the gallbladder

H. Pylori For a long time it was thought that diet, and lifestyle caused Ulcers H. Pylori is a bacteria that burrows itself into the lining of the stomach and causes an ulcer

Respiration What respiratory structures do we all share? What respiratory structures enable animals to breath? How do aquatic animals breath?

Gas Exchange All animal tissues need oxygen for respiration, and produce carbon dioxide as a waste product Humans would drown if they tried to ‘breath’ water, out of water fish have the same problem

Gills Gills are feathery type structures which expose a thin selectively permeable membrane Inside gills are a network of capillaries

Lungs Organs that exchange oxygen and carbon dioxide between blood and air

Our respiratory system Nose

Pharynx Larynx Trachea

Lungs

Gas exchange

Breathing Movement of _______________, and the ____ ___________ change the air pressure during inhalation and exhalation. Inhalation = ? Exhalation = ?

Diseases Caused by Smoking Chronic Bronchitis- inflamed and clogged bronchi Emphysema- Loss of elasticity Lung Cancer