H B S+ Project(2)
-
Upload
albanyhighschool -
Category
Health & Medicine
-
view
4.176 -
download
2
description
Transcript of H B S+ Project(2)
Chapter 41Animal Nutrition
Kaia Morrow, Jeff Cooper, Kat Malek and Zoë Atlas
Glucose Regulation• Energy is stored as
glycogen, which can be secreted if needed
• Insulin decreases blood glucose
• Glucagon increases blood glucose
• Glucose regulation is maintained by a negative feedback mechanism
Deficiency Diseases
• Malnutrition - lack of essential nutrients
Ex. The protein deficiency Kwashiorkor causes the swelling of the belly because blood cannot absorb as much water from the body cavity through osmosis because of the lack of blood proteins
• Undernourishment - calorie deficiency that can lead to starvation and death
Essential Nutrients - Proteins, Carbohydrates and Lipids
• Proteins - broken down and used as fuel
• Carbohydrates - oxidized for the generation of ATP, energy-rich, organic
• Lipids - provide ATP when oxidized during cellular respiration, energy-rich, organic, stores energy in the form of glycogen
Essential Nutrients - Vitamins and Water
• Vitamins - organic molecules, necessary in small amounts (0.01 to 100 mg/day), have diverse physiological functions
• Water - used by water-soluble vitamins that function as coenzymes in metabolic processes
Essential Nutrients - Minerals
• Minerals - inorganic compounds, required in small amounts (less than 1 to 2,500 mg/day)
Essential Amino Acids
• Amino acids are required to make proteins
• Essential amino acids cannot be synthesized by the body, so they must be consumed though diet
Modes of Heterotrophic Nutrition
• Carnivores - eat meat• Herbivore - eat
vegetation• Omnivores - eat both
meat and vegetation
Four Main Stages of Food Processing
• Ingestion - the act of eating• Digestion - the act of breaking
up food into molecules small enough for the body to absorb
• Absorption - animal cells take up small molecules such as amino acids and simple sugars from the digestive compartment
• Elimination - wastes are eliminated from the body
Intracellular Digestion
• Food particles are taken in by endocytosis and digested inside of food vacuoles
• Occurs safely within a compartment that is enclosed by a membrane
food vacuole
Food Vacuoles
• Simplest digestive compartment
• Used by heterotrophic protists
• Fuse with lysosomes
Extracellular Digestion
• In extracellular digestion, Hydrolysis occurs outside of cells (in an alimentary canal or gastrovascular cavity)
• Advantage - it allows an animal to digest larger prey than can be intracellularly digested
Adaptive Value of the Alimentary Canal
• The alimentary canal moves food one way down the canal and can be organized into special regions for digestion
Changes to Food in the Mouth
• Bacteria is killed by the saliva in the mouth
• Food shape
changes and
becomes a
bolus
Oral Cavity, Pharynx, and Esophagus
• Lubricate food and begin digestion
• Carry food into the stomach through peristalsis
• Salivary amylase breaks down food for preparation of full digestion
Stomach• Churns and digests food
with hydrochloric acid and the enzyme pepsin
• Porous walls of stomach secrete hydrochloric acid and pepsin to digest food
• Walls of the stomach are coated with mucus to protect them from gastric juices
Secretions of the Duodenum
• Acid chyme from the stomach is combined with digestive juices fromthe pancreas, gallbladder, liver, and gland cells of the intestinal wall
• Hydrolytic enzymes from the pancreas are activated in the duodenum
• Bile is produced by the liver and secreted into the duodenum, aiding in fat digestion
• Digestive enzymes enter the duodenum from the epithelial lining
Pancreas Peptidases
• The pancreas prevents digesting itself by producing enzymes and bicarbonate-rich solutions
• Bicarbonate is a buffer that offsets the enzyme’s acidity, and allows their secretion in an inactive form
• Once in the intestine, the enzymes are activated
Human Digestive System
Location of Carbohydrate, Protein, Nucleic Acid, and Fat Digestion
• Carbohydrates- oral cavity, pharynx, esophagus, lumen of small intestine, epithelium of small intestine
• Protein – stomach, lumen of small intestine, epithelium of small intestine
• Nucleic Acid – lumen and epithelium of small intestine
• Fat – lumen of small intestine
Small Intestine and Features that Improve Its
Function• Major organ of digestion and
absorption• The brush border, or epithelial lining
of the duodenum, provides many digestive enzymes
• Microvilli increase the surface area and rate of nutrient absorption
• Lacteals are vessels of villi that carry lymph and absorb nutrients, putting them into the bloodstream
• The hepatic portal vein leads directly to the liver, ensuring that it is supplied with the nutrients absorbed in the small intestine
Roles of Gastrin, Secretin, and Cholecystokinin
• Gastrin - begins gastric juice production• Secretin - discharge into the filtrate from wastes of the body• Cholecystokinin -
Causesdigestive enzyme release
Large Intestine
• Functions as a home for vitamin-synthesizing bacteria
• Aids in the absorption of water
Dental Adaptations
• Dentistry of
mammals is usually
specialized for their
diet
Stomach and Intestinal Adaptations of Herbivores
• As vegetation has cell walls that are difficult to digest, herbivores have longer alimentary canals than carnivores
• Many herbivores have fermentation chambers specialized for cellulose digestion