biology option D Flashcards
CLASSES OF NUTRIENTS (6)
carbohydrates, proteins, lipids, vitamins, minerals and water
malnutrition
health condition caused by a deficiency, imbalance or excess of nutrients in the diet.
it is caused by improper diet
anorexia, how is it caused, symptoms, etc.
psychiatric illness caused by voluntary (sometimes not) starvation and loss of body mass. the amounts of nutrients consumed are too less of what the body’s energy requires.
results:
There is wasting of muscles, resulting in loss of strength, infertility, hair loss, slow heart rate, poor circulation.
skeletal muscle is digested and heart muscle deteriorates
(breakdown of the heart muscles)
exocrine glands function
produce and secrete substances onto an epithelial surface - on the body or the lumen of the digestive track
what controls the secretion of the digestive juices
mechanical, nervous and hormonal mechanisms.
sympathetic system controls what
FIGHT OR FLIGHT
controls processes involved in responses to danger. it slows down the digestion when there is no food available
parasympathetic system controls what
REST AND DIGEST
homeostasis and processes related to rest and digestion., it speeds up digestion when food is ingested
essential nutrients
those that cannot be synthesized by the body therefore must be ingested as part of the diet.
non-essential nutrients
those that can be made by the body or can be replaced
how to find BMI
kg\m2
iron defficiency and how to get it form
anemia, fatigue, poor concentration, not enough oxygen
get iron from meat and spinach
Vitamin C defficiency and where to get it from
it can get you scurvy - this condition involves bone and blood vessel disease, bleeding in the hands
you can get it from citrus, bell pepers and broccoli
energy homeostasis
process that regulates food intake and energy flow
which part of the brain receives signals from fat cells that they are hungry?
hypothalamus
scurvy symptoms, causes, treatment
causes - not enough Vitamin C
symptoms - joint, muscle or leg pain, teeth falling out, skin bruises easily
treatment - eat vitamin C
PKU symptoms, causes, treatment
treatment - taking a PKU formula to make sure you have enough essential protein
causes- a change in the gene PAH, it makes the acid built up in the body
symptoms - being sick, behavioural dificulties, different skin and color of eyes
rickets causes symptoms and treatment
symptoms - pain, skeletal deformities
causes - lack of vitamin D or calcium
treatment - increasing the intake of vitmain D or calcium
osteomalacia causes symptoms and treatment
causes - lack of vitamin D or calcium
symptoms - pain in the bones and joints, bones break easily, difficulty walking
treatment- vitamin D or calcium, phosphate supplements
concequences of obesity
heart problems, cancer, diabetes
which hormone affects apetite
leptin, it supresses the apetite targeting hypothalamus part of the brain
Determination of the energy content of food by combustion.
First, the mass of the food is being recorded by a scale.
The mass of the water that is going to be heated is measured by a scale.
The temperature of the water is being recorded by the thermometer.
The food is being burned or heated (combusted) below the water to release energy in a form of heat.
measuring the increase of the temperature comparing the initial temperature and the changed temperature.
The energy is calculated by the formula:
Q (J) = Mass of water (g) × 4.2 (J/gºC) (the heat capacity of water) × Temperature increase (ºC)
to find it per a gram of food, you divide by the mass of a food.
calorimeter can be used
which nerves are involved in the digestion
the medulla of the brain sends nerve impulses to the stomach
the stretch receptors of the stomach send nerve impulses to the secretory cells of the gastric glands
mucus cells in gastric pits
secrete mucus
pariental cells in the gastric pits
responisble for gastric acid secretion which aids in the digestion, and control of harmful bacteria
chief cells in gastric pits (explain how the product changes itself)
secrete pepsinogen which is a proenzyme which than changes from inactive enzyme in the acidic environment to an active acid (pepsin) to not digest the cell it is produced in.
pepsinogenbreak down proteins
G-Cells in the gastric pits
secrete the hormone gastrin into the blood it helps fro growth o the gastric mucosal.
which hormones are involved in the chemical control of digestion
gastrin, secretin and somatostatin
mechanical mechanism
chewing, mixing and squeezing food in the stomach, it controls the secretion of digestive juice - the body prepares for some food
chemical mechanism
stomach acids, bile and enzymes