2.24-2.33 Human Nutrition Flashcards
What is important for a balanced diet
Apropriate proportions of carbohydrates, protein, lipids, vitamins, minerals, water and dietary fibre
Carbohydrate : functions and where to find it
Provides energy
found in pasta,rice, sugar
Protein : functions and where to find it
needed for growth and repair of tissues
found it meat and fish
Lipids : functions and where to find it
to provide energy and act as an insulator
found in butter & oily fish
Name 3 vitams, their function and where to find it and deficiency
Vitamin A: found in oily fish and dairy products needed for growth and development as well as good vision
deficiency- night blindness
Vitamin C: found in citrus fruits needed for healthy teeth and gums
deficiency- scurv
Vitamin D: found in dairy products and produced by body using sunlight needed for strong bones and teeth
deficiency- rickets
Name 2 minerals, their function and where to find them and deficiency
Calcium: found it dairy products, needed for strong bones and teeth
deficiency-rickets
Iron: component of heamoglobin which helps bind oxygen to blood
deficiency- anemia
Teeth function
to break down food
Salivary gland function
produces amylase enzyme in the saliva
Tongue function
helps the movement of food and assists swallowing
oesophagus function
the muscular tube that conects the mouth and stomach
liver function
regulates most chemical levels in the blood and excretes a product called bile
stomach function
pummels the food with its muscular walls
produces protease enzymes
produces hydrochloric acid to kill bacteria with an optimum of ph 2
Pancreas function
produces protease amylase and lipase enzymes which it releases into the small intestide
large intestine function
also the colon
excess water is absorbed from food
small intestine function
produces protease amylase & lipase enzymes to complete digestion
nutrients are absorbed
first part is the duodenum and the last part is the ileum
rectum function
last part of the large intestine
where feaces are stored
anus function
feaces exit the body through the anus
ingestion definition
the consumtpion of a substance
digestion definition
breaking down large food molecules into small food molecules
absorption definition
digested food molecules are absorbed by the small intestine into the blood
assimilation meaning
small food molecules used to build up larger food molecules
egestion meaning
removing feaces from the anus
excretion meaning
removal of cell waste
explain how food is moved through the gut by peristalsis
peristalis is the process which food is moved through the oesophagus and intestines using the muscles of their walls which contract and relax rythmically to move the food along
How is the small intestine adapted for its function?
Has villi which has :
-a large surface area for absorption
-short diffusion pathway (one cell thick)
-maintain a concentration gradient between the food in the ileum and the blood
-have a network of lymphatic vessels called lacteals
where is bile produced and stored and what is its function
produced in the liver and stored in the gallbladder used to neutralize stomach acid and emulsify lipids
Experiment used to investigate energy content in a food sample
-weigh a small amount of dry food and skewer it onto a mounted needle
-add a set volume of water to a boiling tube held by a clamp
-measure the temperature of the eater then set fire to the food using a bunson burner
-hold the burning food under the boiling tube until the flame goes out. Repeat until food wont catch fire again
-lastly measure the temperature of water again
how to calculate energy in food
energy in food (in J)=
mass of water (in g)
X
temperature increase
X
4.2
all divided by mass of food sample
