7 Human Nutrition Flashcards
balanced diet
a diet differeing in foods so that the requirement for calories, proteins, minerals and vitamins and nutrients is adequate
importance of carbohydrates
bodys main fuel source
importance of fats and oils
helps your body absorb fat-solutble vitamins such as A, D, E and K
importance of proteins
help body repair cells and make new ones
importance of vitamin C
forms an essential part of collagen protein, which makes up skin, hair, gums and bones.
- deficiency causes scurvy
importance of vitamin D
help absorb calcium for strong teeth and bones
importance of calcium
- needed for strong steeth and bones
- involved in the clotting of blood
- deficiency can lead to osteoporosis
importance of iron
required for the formation of haemoglobin
importance of fibre
acts as a bulking agent to the body and helps remove waste (cannot be digested)
importance of water
keep a normal temperature, lubricate and cushion joints, protect organs, rid of wastes
scurvy caused by
not having enough vitamin C in your diet
rickets caused by
a lack of vitamin D or calcium
main digestive system organs
alimentary canal: mouth oesophagus, stomach, small intestine, large intestine
associated digestive system organs
salivary glands, pancreas, liver and gall bladder
ingestion
taking in of substances - food and drink - into the body
digestion
the breakdown of food
absorption
the movement of digested food molecules through the walls of the intestine and into the blood
assimilation
movement of digested food molecules into the cells of the body where they are used, becoming part of the cell
egestion
the removal of undigested food from the body as faeces
physical digestion
breakdown of food into smaller pieces without chemical change to the food molecules
why does physical digestion occur?
it increases the surface area of food for the action of enzymes in chemical digestion
enamel
hard, calcified outer covering used to break down food
dentin
softer, more vulnerable material which is the tooths last defense for the tooth pulp if enamel is broken/dissolved
cementum
calcified connective tissue which attaches tooth in jaw, keeping it firmly in place
insisors
four front teeth in the upper and lower part of jaw. single root and a sharp incisal edge. function is to cut food
canines
four next teeth next to incisors. single pointed cusp and a single root. function to tear food
premolars
positioned after canines. function to crush and grind food
molars
furthest teeth away from the front. broader and flat. function to grind food
bile role
- emulsifies fats to increase their SA for enzymes to digest them
- An akalali mixture that neutralises acidic mixture of food and gastric juices entering the duodenum from the stomach - to provide a suitable pH for enzyme activity
oesophagus
carry food and liquid from your mouth to your stomach
mouth
breaks down food into smaller pieces, amylase from salivary glands break down starch
stomach
- creates digestive juices and breaks down food
- contains muscles that
contract to mix food wiht the strong digestive juices - hydrochloric acid kills harmful microorganisms in food and provides a pH of 2 for opt enzyme activity
pancreas
produces pancreatic juices to digest substances (amylase, protease, lipase)
liver
produces bile and stores it in the gallbladder, detoxifies alcohols, de and reamination
small intestine
further digests food with the pancreatic juices, most water is absorbed here
large intestine
absorbs water and electrolytes, producing and absorbing vitamins, forming and propelling faeces towards the rectum for elimination
villi
tiny hair-like projections that are made up of cells that line the lining of the small intestine. it absorbs nutrients and shuttle them into your blood stream
chemical digestion
break down of large insoluble molecules into small soluble molecules that can be absorbed
amylase
breaks down starch into maltose produced in the salivary glands and pancreas, yet used in the mouth and small intestine
pepsin
breaks down proteins into amino acids produced and used in the stomach
(acidic conditions)
trypsin
breaks down proteins into amino acids produced in the pancreas and used in the small intestine
(alkaline conditions)
lipase
breaks down fats and oils into fatty acids and glycerol produced in the pancreas and use in the small intestine
Peristalsis
series of muscle contractions that help move substances from mouth to stomach
Treatment of CHD
Angioplasty (balloon inserted into artery)
Bypass graft (make another way for blood to pass)
Heart Transplant
lacteal (villi)
absorbs fatty acids and glycerol
blood capillary (villi)
absorbs glucose and amino acids
thin epithelium purpose (villi)
one cell thick to increase diffusion rate
microvilli to increase surface area for absorption
maltase
breaks down maltose to glucose on the membranes of the epithelium lining in the small intestine
Some of the cells on the surface of the villi secrete mucus for protection.
Suggest what the villi need to be protected against
protected agaisnt the enzymes and stomach acid, so no physical damage happens.
(against pathogens)
anus
(part of large intestine)
where indigestible food is egested
effects of build up of cholesterol
cause CHD/heart attack/cardiac arrest;
reduced blood flow/blockage of artery/arteries;
damaged artery wall;
aneurysm;
causes high blood pressure;
reduced supply of oxygen to heart muscle;
muscles respires anaerobically;
