nutrition+diet exam questions

• what is the function of fibre in the diet


  to help push food through the small intestine
• give 2 effects of lack of fibre in the diet

  -constipation -risk of bowel cancer
• how does food move along the oesophagus

  through a process called peristalsis which is the contraction of muscle tissue
• which 2 organs is the pancreas in between

  stomach, small intestine
• what is the function of villi (in small intestine) 


  to absorb digested food
• give 2 reasons why not all the heat given off by the burning food is absorbed by the water

  -some energy is lost in the atmosphere -some energy is absorbed by glass
• what is the relationship between the temperature rise and the energy content of food

  the higher the energy content, the more the temperature will increase
• what is present in a peanut that makes it burn readily

  fat
• what is left at the end of an experiment when foods are completely burnt

  carbon
• what is the use of iron in the body

  iron is a key component of haemoglobin, a protein in our red blood cells which transport oxygen around the body. The lack of these blood cells is anemia where you dont receive as much oxygen to ur tissues
• what is the use of vitamin d in our body

  absorbing calcium from food. deficiency disease is rickets (soft bones and teeth
• what is the role of vitamin c in our body


  to keep skin and blood VESSELS healthy
• why do people with anemia always feel tired


  anemia is when you do not have as much red blood cells to transport oxygen to your tissues. there is less oxygen meaning less is reaching our muscles and there is not enough respiration to release energy
• explain why too much fat in the diet is unhealthy

  -can lead to obesity if not eaten in correct amounts -can lead to high cholestrol
• where does the digestion of protein begin

  stomach
• digested foods are absorbed into the blood and carried to the liver. which blood vessel do they travel through

  hepatic portal vein
• what happens to excess glucose when it reaches the liver

  it changes to glycogen
• what is the hormone released which controls the process of excess glucose changing to glycogen in the liver

  insulin
• where is the hormone inulin produced

  pancreas
• in liver excess amino acids are deaminated. what chemical is produced as a result of this deamination

  urea
• where is urea transported to

  the kidneys
• urea is transported to the kidneys. which 2 blood vessels does this chemical travel through

  hepatic vein, vena cava
• what is the purpose of digestion

  it breaks down large insoluble food molecules into smaller soluble food molecules, allowing our bodies to absorb them
• what are 2 conditions present in the stomach which are needed for enzyme action/ protease

  -it has hydrochloric acid which provides the right pH for an enzyme to work -it has a suitable temperature of 37 degrees
• dialysis tubing is described as selectively permeable. what does this mean?


  it allows small particles to pass through but restricts larger ones
• what is the liquid inside the visking tube representing

  food
• what is the liquid outside the beaker in a model gut experiment representing

  blood
• what is the difference in size of a starch and glucose molecule

  starch is a bigger molecule than glucose
• what are 3 digestive juices

  pancreatic juice, gastric juice, saliva
• where is gastric juice produced

  stomach
• what is 1 process by which digested food is absorbed

  diffusion
• describe what happens to food that is not digested and absorbed

  water is absorbed from the food and forms faeces which are stored in the rectum and released from the anus
• use term monomer and polymer to explain difference between simlpe sugars and complex carbohydrates

  complex carbs are polymers while simple sugars are monomers as complex carbs are large molecules made out of smaller sugar molecules
• what can herbivores digest that we cant

  sodium
• what type of appartus do you need in order to measure the energy in food


  boiling tube, water, stop watch, mounted needle, measuring cylinder, thermometer, clamp stand, bunsen burner
• what is the calculation for finding the energy in a crisp

  20 x 4.2 x temp rise of water = energy in crisp (J) change from joules to kilojoules by dividing by 1000
• how do you find the energy per g of crisps

  energy in crisp (J) / mass of crisp (g)
• why are our results from the practical not the same as on the packet

  they are lower as: the entire food sample might not be burned, some energy is lost in the atmosphere, some is used to heat the glass of the boiling tube
• what are some of the control variables of the energy in crisp experiment

  mass of food, mass of water, distance from food from water
• how do we know that the food has a lot of energy from the experiment

  a large increase in temperature