chapter 7 animal nutrition Flashcards
(21 cards)
what is a balanced diet
a diet that contains the correct proportions of nutrients that the body needs to function correctly (eg. carbohydrates, lipids, proteins)
which general group of people require the most calories in their diet
adolescent males with active lifestyles
why do pregnant/breastfeeding women need a larger caloric intake
they need more energy to support the development of the child
the diet needs to be balanced as well to provide the correct nutrients
what is constipation caused by
a lack of dietary fibre
what is starvation
suffering or death caused by not eating enough food
what is constipation
infrequent bowel movements causing difficulty passing faeces
what is scurvy caused by
a lack of vit C
What contributes to differentiating energy requirement
Activity levels Age Pregnancy Lifestyle Climate Metabolic rate Health/medical conditions
From the mouth the food passes through the pharynx (back of throat) and then where?
Down the oesophagus
What is peristalsis?
Waves of muscular contraction followed by relaxation that pushes food down the oesophagus and down into the stomach. It occurs along the entire length of the digestive system
How is the oesophagus adapted to suit its function as a passage way?
Muscular
Mucus is produced from goblet cells to reduce friction
Describe three main events that take place in the stomach
HCL is produced. This gives the correct ph for the enzyme pepsin to work. Acid also kills any ingested bacteria
Mechanical digestion by peristaltic movements
Chemical digestion. Pepsin realised from stomach lining and breaks large protein molecules down to amino acids
Where is bile produced and stored
Produced by liver, stored by gall bladder
Why do we need bile
Neutralises stomach acid and emulsifies lipids
From the stomach the food enters a region of the small intestine called the
Duodenum
What is the alimentary canal?
The whole digestive system.
What happens in the duodenum
Pancreatic juices from the pancreas neutralises stomach acid and more enzymes are added.
What is the other part of the small intestine called?
The ileum
What happens in the ileum
Small molecules (final products of digestion) e.g glucose, amino acids, fatty acids and glycerol, vitamins and minerals are absorbed.
How is the ileum adapted to its absorption role?
The whole surface is folded and covered with villi
What passes into the large intestine?
Digestion is finished by this point and the waste material consists of fibre and water and some dead or living bacteria
