BIO2

• Nutrition is a substance that is needed for the growth and maintenance of an organism
• Autotrophs and Heterotrophs are two modes of nutrition based on the type of organism
• Autotrophs are organisms that obtain energy from sunlight and chemicals to produce their own food
• Heterotrophs are organisms that cannot make their own food and obtain energy from other organisms
• Autotrophs are self feeding that obtain their energy from the environment
• Autotrophs are the producers
• Types of Autotrophic nutrition are photosynthesis and chemosynthesis
• photosynthesis use energy from sunlight to produce organic molecules
• chemosynthesis use energy from oxidation of inorganic compounds
• heterotrophs obtain energy from other living things
• heterotrophs are the consumers
• types of heterotrophic nutrition are saprotrophic, parasitic, and holzoic
• saprotrophic obtain energy from dead plants, dead and decaying animal bodies
• parasitic feeds on another living organism
• holzoic obtain energy from the ingestion of organic food materials
• types of feeding adaptations are suspension/filter feeders, substrate feeders, fluid feeders, and bulk feeders
• suspension or filter feeders sift food from water
• substrate feeders live in or on their food
• fluid feeders sucks fluid from a host
• bulk feeders eat large pieces of food
• two types of system are incomplete digestive system snd complete digestive system
• incomplete digestive system - one way, saclike digestive system
• complete digestive system - tube with an opening at each end
• digestive system - performs processes of digestion, absorption of nutrients, and elimination of waste
• digestion - breakdown of food into smaller form
• digestion involves ingestion, peristalsis, digestion, absorption, defecation
• two types of digestion - mechanical digestion and chemical digestion
• mechanical digestion - ingested food are broken down into smaller pieces by chewing or mastication and peristalsis
• chemical digestion - food id acted upon by catalytic enzymes to be broken down into its absorbable form
• oral or buccal cavity or mouth - responsible for sense of taste
• oral or buccal cavity or mouth - responsible for mechanical breakdown of food and chemical digestion of carbohydrates
• ptylin - salivary amylase in the saliva
• pharynx - common passageway for food and air where swallowing begins
• esophagus - 25 cm or 10 inches long that secretes mucus and transport food through peristalsis
• peristalsis - smooth muscle contractions that push food through a sphincter
• sphincter - ring shaped muscle that open or close a passageway in the body
• stomach - mixes and stores ingested food, secretes hydrochloric acid and digestive juices
• small intestines - where enzymatic hydrolysis occurs and absorption of digested food by its villi
• small intestines - 6 meters long divided into three parts : duodenum, jejunum, and ileum
• duodenum - 25 cm or 10 inches long, complete digestion of food by enzymes