Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
15 Cards in this Set
- Front
- Back
|
* Food |
* any material that contains nutrients |
|
|
* Nutrients |
* substances an organism needs to stay alive, such as amino acids, vitamins, minerals, and electrolytes |
|
|
Digestion |
is the breakdown of food into small enough pieces to allow for absorption (the uptake of nutrients) |
|
|
What four processes are necessary to obtain energy and nutrients from food? |
Four processes are needed to obtain energy from food – ingestion, digestion, absorption, and elimination |
|
|
What are the different food capturing strategies? Briefly describe each. |
Food Capturing Strategies *Suspension feeders filter small organisms or bits of organic debris from water, by means of cilia, mucus-lined “nets”, or other structures (sponges) * Deposit feeders swallow organic-rich sediments and other types of deposited material (earthworms) * Fluid feeders suck or lap up fluids (hummingbirds) Mass feeders seize and manipulate chunks of food by using jaws, teeth, beaks, or special toxin-injecting organs (most animals) |
|
|
1. Compare and contrast the complete vs. incomplete digestive tract |
1.
Digestion Digestion is the breakdown of food into small enough pieces to allow for absorption (the uptake of nutrients) 2. Two general schemes: 3. Incomplete digestive tracts have one opening for both ingestion of food and elimination of wastes. Digestion takes place in a gastrovascular cavity Complete digestive tracts have two openings, the mouth for ingestion, and the anus, for elimination of wastes. In addition to the gastrointestinal (GI) tract, auxiliary components contribute to the digestion process |
|
|
Be able to identify the structures and functions of the human GI tract and its accessory organs. Also be able to tell what is part of the GI tract and what is an accessory organ. |
The Human Digestive System (GI tract) 1. mouth 2. esophagus 3. stomach 4.small intestine 5.large intestine 6. appendix 7. anus
|
|
|
Where does carbohydrate digestion begin? Protein digestion? Lipid digestion? |
* Carbohydrate digestion begins in the mouth (amylases break down the carbs) * Protein digestion begins in the stomach (pepsin breaks down the protein) Lipid digestion begins in the small intestine |
|
|
Chief cells |
secrete pepsinogen |
|
|
Parietal cells |
secrete HCl, which denatures proteins |
|
|
Mucous cells |
secrete mucous, which protects against HCl damage. Gastric juice can have a pH as low as 1.5 |
|
|
Why does the small intestine have an enormous surface area? |
• The enormous surface area of the small intestine increases the efficiency of nutrient absorption. |
|
|
What is the function of the large intestine? |
* When solutes are absorbed in the small intestine, water follows by osmosis * The large intestine compacts the remaining waste and absorbs enough water to form feces. Aquaporins play a key role in this o Colon – main section The size and function of the large intestine varies dramatically among animals o Symbolic bacteria may also digest cellulose |
|
|
1. How do insulin and glucagon help maintain blood glucose levels? |
o Insulin is produced in the pancreas when blood glucose levels are high o Insulin causes cells to increase their rate of glucose uptake, which decreases blood glucose levels 1.Nutritional Homeostasis Too much or too little of a nutrient can be problematic or even fatal 2. People with the disease diabetes mellitus experience abnormally high levels of glucose in their blood 3. The disease is caused by problems with the hormone insulin 4. If blood glucose levels fall too much, cells in the pancreas secrete glucagon, another hormone 5. In response to glucagon, cells in the liver catabolize glycogen and produce glucose o Blood glucose levels rise Insulin and glucagon form a negative feedback system |
|
|
What do the pancreas secrete? What are the functions of these enzymes? |
• Insulin and glucagon provide negative feedback in a homeostatic system. Both insulin and glucagon are secreted by cells in the pancreas but have opposite effects on blood glucose levels |
