11 nutirtion - modes

describe autotrophic and heterotrophic

auto: organisms makes their own food from inorganic materials

hetero: organisms cant make their own food and need to consume complex organic molecules produced by autotrophs

what are the types of autotrophs?

photoautotroph: organisms use light as the nergy source to make their own food

chemoautotrophic: organisms use the energy from chemical reactions

describe saprotrophic nutrition

used by fungi and sime bacteria, feeding on decaying matter (eg. rhizopus)

describe holozoic nutrition

used by mist animals where food is ingested, digested and egested (eg. amoeba)

describe ingested, digested, egested

ingwsted: food into body

digestion: breakdown

adsorbed: passage of molecules and ions through gut wall into blood

egestion: elimination of waste

structure of a gut wall

lumen

epithelium

mucosa

submocosa

muscle layer

serosa

describe a endoparasite and how it can live a while

• eg. pork tapeworm

• lives inside the organisms body, in which benefits itself but not the host

• ribbon like body in sections (proglottids)

• scolex - anterior end, made of muscle carrying suckers and hooks

• primary h: human, secondary host: pig

• pig becomes infected when its food is contaminated with human faeces

• hunans are then infected by eating undercooked pork

maintaining the tapeworms cyce

how does a endoparasite survive and what conditions it has to survive in

survived by the conditions of the gut

• living in surrounded by digestive juices and mucus

• experiencing pH changes

they must:

• penetrate and attach to the howt

• protect itself against the host’s immune response

• produce many eggs for transmission into 2° host

• intermediate host

• resistant stages while away from host

describe a ectoparasite and its life cycle

parasite that lives ontop of a body

• nits are empty eggs, easily seens

• after 1-2 weeks eggs hatches (nymphs)

• then becomes adults about 10 days and feeds on blood (scalp)

describe and explain the digestive system

1. mouth (buccal cavity mechanically digests) contains amylase, breaksdown starch

2. oesophagus (muscles to bring food down), sphinter prvent food leaving, goblet cells secrete mucus

3. STOMACH - bile (neutralises and emuksifies fats), gallbladder (stores it) chem and mech breakdown, pancreas and acidic (HCl)

4. small intestines - duodenum to ileum , where nezymes are released from pancreas (lipase, carbohydrase, amylase)

5. large intestines - colon, abosrbs water

6. rectum, waste products eliminated

explain the enzymes in the stomach

1 cheif cells → peosinogen →(HCl) pepsin (endopeptidase)

2a trypsinogen →(enterokinase) trypsin (endopeptidase)

2b sucrose (sucrase) → glucose and fructose

lactose (lactase)→glucose and galactose

maltose (maltase)→glucose

3 exopeptidase (peptides to amino acids)