Paragraphs Flashcards
1
Q
Inspiration
A
- the external intercostal muscles contract, raising the rib cage
- the muscles of the diaphragm contract and the diaphragm flattens
- the volume of the thoracic cavity increases
The air pressure inside the lungs decreases below the the atmospheric pressure - the difference in air pressure allows air outside the body to flow into the lungs and equalise the pressure.
- the lungs inflate with air
2
Q
Expiration
A
-the external intercostal muscles relax and rib cage moves inwcavityards and downwards due to gravity
- the diaphragm relaxes and returns to its dome shape
- the volume of the thoracic decreases
- the air pressure inside the lungs increase above atmospheric pressure
- this difference in pressure allows air to be forced out of the lungs into the atmosphere
3
Q
ADH in osmoregulation on a hot day/ sweating/ loss of blood/ dehydration/ exercising
A
- The stimulus: Change in the amount of solutes in the blood increases osmolarity
- That information is sent to the and the hypothalamus registers that there is excessive salt in the blood and starts the process
- the pituitary gland/ hypophysis secretes more anti diuretic hormone (ADH)
- this hormone is sent to the distal convoluted tubule and collecting duct inside the nephron making them more permeable to water in order to absorb more water
- This causes more water to be reabsorbed
- Because of this only a small amount of concentrated urine is produced
- finally equilibrium is restored in terms of the amounts of solute and water in the body
4
Q
ADH in osmoregulation on a cold day/ inactive/ drinking lots of liquids/ resting
A
- The stimulus: Change in the amount of solutes in the blood decrease osmolarity
- That information is sent to the hypothalamus and the hypothalamus registers that there is excessive water in the blood and starts the process
- the pituitary gland/ hypophysis secretes less anti diuretic hormone (ADH)
- this hormone is sent to the distal convoluted tubule and collecting duct in the nephron making them less permeable to water in order to absorb less water
- This causes more water to be lost
- Because of this a large amount of diluted urine is produced
- finally equilibrium is restored in terms of the amounts of solute and water in the body
5
Q
Aldosterone and salt equilibrium maintenance. Fixing imbalance caused by: excessive sweating/ loss of blood/ drop in blood pressure
A
- stimulus: a change in osmolarity occurs, salt concentration is decreasing
- the sensory cells that line the afferent arteriole recognise the change and secrete the hormone, renin.
- the renin triggers the production of the hormone, angiotensin.
- this information is recognised by the adrenal gland and in response it secretes aldosterone
- Aldosterone is sent to the distal convoluted tubule which increases the amount of sodium absorption back into the blood
- equilibrium is restored
6
Q
Nutrition: Absorption of carbohydrates
A
- Starch is acted upon by the enzyme salivary amylase in the mouth in an alkaline medium
- The starch is broken down to maltose. This also happens in the small intestine when amylase from pancreatic juice acts on the remaining starch
- The maltose is then broken down to its monomers, which is glucose, by the enzyme maltase which is secreted by the intestinal glands (intestinal juice)
- the glucose is then absorbed into the blood capillaries of the villus by passive diffusion and transported to the liver by means od the hepatic portal vein
7
Q
Nutrition: absorption of proteins
A
- protein is acted upon by the enzyme pepsin in the gastric juice of the stomach in the mouth (in an acidic medium).
- The protein is broken down to polypeptides. This also happens in the pancreas when trypsinogen changed to trypsin from pancreatic juice acts on the remaining protein
- The polypeptides is then broken down to its monomers, which is amino acids, by the enzyme erepsin which is secreted by the intestinal glands (intestinal juice)
- the amino acids are then absorbed into the blood capillaries of the villus by passive diffusion and transported to the liver by means od the hepatic portal vein
8
Q
Nutrition: absorbing fats
A
- Fat is acted upon by the enzyme lipase in the pancreatic juice in the pancreas
- The fat is broken down into glycerol and free fatty acids. This also happens in the small intestine when lipase in the intestinal juice acts on the remaining fat.
-Glycerol is water soluble so it can be absorbed by the villus - Fatty acid is insoluble so it combines with bile in order to enter the villus
- Inside the villus the fatty acids and glycerol reform and enter the lacteal (structure running down the middle of the villus) a part of the lymphatic system.
- once the this reformed substance mixes with the lacteal it is know as chyle
- finally fat us absorbed by the body
9
Q
Ultrafiltration
A
-Blood flows from the afferent arteriole into the glomerulus (network of blood capillaries)
- Some of the plasma from the blood capillaries passes
10
Q
Gaseous exchange in the alveoli
A
- Deoxygenated blood flow into the alveoli from the body tissues
- the air breathed into the alveoli has a high concentration of oxygen
- this concentration gradient allow diffusion of oxygen in the air into the blood capillaries
- oxygen diffuses through the thin wall of the alveolus and capillary into the blood
- the blood becomes oxygenated and leaves the lings ans passes through the heart to the tissues of the body
- the capillaries around the alveoli contain high concentration of co2 waste from respiration while the air in the alveoli is oxygenated.
- this concentration gradient allows co2 to diffuse out of the blood into the air in the alveoli to be exhaled
