Flashcards in Chapter 7- Human Nutrition Deck (45)
What are examples of some essential nutrients?
Unsaturated fatty acids
Why are some nutrients essential and some non-essential
The nutrients that are non essential, another nutrient can be used for the same purpose or because they can be made in the body from another nutrient - essentials can't
Examples of no -essential nutrients?
What is an example of conditionally essential nutrients
Vitamin K is produced by the metabolism of symbiotic bacteria in the intestine- infants don't have colonies of this bacteria so at birth they are given supplementary injections
What is vitamin C what does it do
Is a compound called ascorbic acid- needed for the synthesis of the collagen fibres that form
Part of the tissue in the body- most plants and animals can synthesis vitamin c in the body
Why in some animals do it they not produce vitamin C?
Due to mutations that led to genes no longer producing the protein necessary to make vitamin C- due to mutation in the GLO gene which codes for the production of the enzyme l-guluno- lactone oxidase
Examples of mammals that cannot produce Vitamin C
Fish- Ray-finned-cod, salmon, herring
What can be the cause of a lack of vitamin C
Why are some amino acids essential in the body?
-of the 20 amino acids only half are that essential because they cannot be synthesized in sufficient quantities- other half can be made from nitrogen compounds
Example of essential amino acids in body
1) threonine and arginine are conditionally essential
Threonine can be synthesized if phenalanine is present
Arginine is produced by healthy living individuals
Example of essential fatty acids?
They cannot be synthesized in the body
Name 3 essential amino acids
What does a lack of essential amino acids affect?
The production of proteins
What is a lack of essential amino acids that affects the production of protein called?
Protein deficiency malnutrition
Why may essential amino acids by lacking?
Due to overall insufficiency of protein in the diet or to an imbalance in the types of protein
Consequences of protein deficiency malnutrition?
Causes a lack of blood plasma proteins which results in fluid being retained in tissues - causes swelling
Child development may be mentally and physically retarded with stunted growth and development disabilities
Adults may undergo serious weight loss
How much minerals are needed on the diet?
Relatively small quantities
What are minerals
Example of mineral deficiency
Iodine- needed by thyroid gland to produced thyroxin - this stimulates the metabolic rate- lack of iodine squads IDD (iodine deficiency disorder)
- pregnant lady may be born with brain damage, mental development and intelligence are impaired
What are vitamins
Chemically diverse carbon compounds that cannot be synthesises by the body
What do vitamins do?
Serve a variety of roles such as co factors for enzymes, anti-oxidants and hormones
What is malnutrition caused by?
Is the outcome of a bad diet- could be a deficiency , imbalance or exceeds of nutrients in the diet
What is starvation ?
Is a consequence of a diet lacking in adequate protein and carbohydrates
Where is appetite controlled from?
Hypothalamus of the brain- appetite control centre
What hormones do the appetite control centre receive to reduce the desire to eat?
Small intestine secrets PYY3-36 when it contains food
Pancreas secreted insulin when blood glucose level is high
Adipose tissues secrets leptin when amounts of fat stored increases
What are the two main consequences of obesity?
Hypertension and type II diabetes
What is diabetes mellitus?
Sugar is present in the urine
Can be developed 2 Ways-
1) auto immune destruction of insulin secreting cells
2) decreased responsiveness of body cells to insulin due to 'burn out'
Type II diabetes have increased blood concentrations of fatty acids - linked to following risk factor ?
Diets rich in fat and low in fibre
Obesity due to overeating and lack of excercise
Genetic factors which affect fat metabolism
What are the symptoms of diabetes II
Elevated levels of blood glucose
Glucose in urine
Dehydration and thirst resulting from excretion of large volumes of urine