Unit 7 - Human Nutrition Flashcards
diet, digestive system, physical digestion, chemical digestion, absorption
What are the seven groups of a balanced diet ?
- carbohydrates
- fats
- proteins
- vitamins
- minerals
- dietary fibers
- water
What are carbohydrates needed for?
primary nutrient for producing energy using respiration
examples of carbohydrates (both simple sugars and starch)
starch : bread pasta potato
simple sugars: cakes , sweets
What are fats/lipids needed for?
- making cell membrane
- storage of energy
- produce fat tissue to stay warm
examples of fats
butter, oil, cheese
What is protein needed for ?
growth and repair. (getting bigger by growing new cells and replacing worn cells)
examples of proteins
meat fish egg beans
What is Vitamin c needed for?
used in creating connective tissue, blood vessels, bones and cartilage.
required for wound healing
What is vitamin d needed for?
helps to basorb calcium from your diet. needed to maintain strong healthy bones
sources of vitamin d
fatty fish, egg yolks, mushrooms, sunlight
What is the fuction of calcium
needed for maintaining healthy bones, for muscle contractions and blood clotting
food examples of calcium
milk, cheese , fish with bones
function of iron
required for making haemoglobin in red blood cells used to bind oxygen.
food examples of iron
red meat, leafy greens, whole grains
function of dietary fibers
ensures food moves through your intestines at the right rate
sources of dietary fibers
fruits and vegetables
function of water
acts as a solvent for cellular reactions, circulatory systems and digestion
helps maintain body temperature
How does the mouth and salivary glands help digest food
- teeth grind food into small pieces
- salivary glands release saliva. the saliva contains amylase enzymes which breaks fown starch into maltose. another enzyme maltase breaks down moltose into glucose
function of the oesophagus in digestion
- back of the mouth food is made into a ball called a bolus
- the bolus is pushed down the oesophagus by rings of muscle.
What is the contraction of digestive muscles called
peristalsis
function of the stomach in digestion
muscles churn food
enzymes( eg pepsin ) are added, hydrochloric acid is added
function of the small intestine
absorbs nutrients, it is made from microscopic villi that help increase the surface area , so more nutrients can be absorbed more quickly.
purpose of cappilaries in villi, what do they transport
reduce diffusion distance (faster diffusion)
transport water, amino acids etc.
what does the lacteal do in villi
absorbs fats
what role does blood have in the small intestine / villi
blood flowing maintains concentration gradient and larger concentration gradient means faster diffusion
what are the 3 parts of the small intestine?
duodenum ileum and jejunum
where is the duodenum and what is its function?
food out of the stomach enters the duodenum where bile and digestive enzymes are added to further digest food
Where is the ileum and what is its function
after the jejunum food wil pass into the ileum where the majority of nutrients are absorbed
function of the large intestine
mainly indigestible food and water enter , job is to basorb water back into the body
function of the rectum and anus
anus is the opening at the end of the digestive system. faeces is stored in the rectum ready to be released
function of the liver and gall bladder
liver produces bile which helps to digest lipids/fats. gall bladder stores bile until it is released into the small intestine
function of the pancreas
produces enzymes involved in digestion
where does physical / mechanical digestion take place
mouth and stomach
physical / mechanical digestion definition
breaking down large bits of food into smaller bits without any chemical change to the molecules in order to maxamise surface area
chemical digestion definition
breaking down large molecules into smaller soluble ones using enzymes
what does ingestion mean
eating food
what does digestion mean
breakdown of food
what does absorbtion mean in digestion
movement of nutrients from the intestines into the blood
what does assimilation mean
movement of nutrients from the blood into the body cells
what does egestion mean
passing of faeces/ undigested food
what are the 4 types of teeth
- canines
- molars
- incisors
- premolars
function of canines
cut and tear up food
function fo molars
teeth that do the most chewing worl while eating
function of incisors
work to bring food into the mouth and cut it
function of premolars
help incisors and canines frind and mix food while chewing
Function of bile in digestion
helps to emulsify fats, increasing the surface area for faster chemical digestion by enzymes
what are the 3 main types of enzymes
carbohydrases
lipases
porteases
function of carbohydrases (amylase)
digest starch into maltose. maltose is digested to glucose by maltase
function of lipases
digest lipids into glycerol and fatty acids
function of pepsin
digest proteins into amino acids
function of trypsin
digests proteins to amino acids
where is amylase produced
- salivary glands
- pancrease and secreted into the duodenum
where are lipases produced
in the pancreas and secreted into the duodenum
where is pepsin found
found in the stomach
optimised for acidic conditions as the stomach contains hydrochloric acid
where is trypsin produced
in the pancreas ad secreted into the duodenum
optimised fro alkaline (bile neuturlaises the hydrochloric acid)
