Excretion Flashcards
What is ADH
Anti- diuretic hormone
Deanination
Conversion of excess amino acids into urea
What is an Endocrine glad
A gland that does not have a duct ( tube) coming out of it
What is a exocrine gland
A gland that has a tube (duct) coming out of it
Egestion
Removal of undigested food material
Excretion
Removal of the waste products of metabolism
Filtration
Removal of materials from the blood
Glomerular filtrate
Content of the blood that has passed through the glomerulus
Homeostasis
The maintenance of a constant internal environment in a living organism
Osmoregulation
Maintaining a constant water level in a living organism
Reabsorption
Returning of filtered material to the blood
Name the source, site of excretion, how it’s made and the excretory product of the organs of excretion.
Protein-Kidneys-filtration and reabsorbtion-urea
Carbs/lipids/proteins-lungs-breathing-Co2 + water Vapor
——-skin-sweating-salts
Excess amino acids- liver-deamination - Bile
Name a method of excretion is plants
Gasses diffuse out of stomata/ lenticels
Why is homeostasis so important in a living organism
So enzymes in the living organism can work at optimism conditions
Functions of the kidney
Execretion
Osmoregulation: maintaining a constant water balance within an organism
Controls PH of body fluids
Where are the kidneys located
Abdominal cavity
Name the associated blood supply of the kidney
Renal artery (comes from aorta/ linked to afferent arteriole) carries O2 and food to the kidney
Renal vein( goes to the vena Cana /linked to efferent arteriole carries CO2 and waste products away from kidney
What is the purpose of the nefron
Increase surface area for filtration and reabsorption
How does the nephron aid the filtration and reabsorption process/ what are its adaptive features
Having a large surface area for greater filtration and reabsorption
Walls of nefron are one cell thick for faster and easier absorption
Surrounded by a good blood supply for aiding in reabsorption and secretion
What is the cortex responsible for
Filtration
What is the medulla responsible for
Reabsorption
Describe associated blood supply of the nefron before urine formation
Blood enters the kidney via the afferent arteriole ( coming from renal artery) The afferent arteriole is larger than the efferent arteriole so that it creates pressure and forces the blood out the arteriole in high pressure to enter the gllmerulus
Describe the process of filtration
Some of the contents ( amino acids, glucose, water , salts and urea)is passed through the glomerulus and become known as the glomrulus filtrate. The filtrate is collected by the Bowman’s capsule and passed to the proximal convoluted tube
Describe the process of reabsorption
The glomerulus filtrate is mostly absorbed by the proximal convoluted tubule . expect Urea
Glucose, AA, vitamins are reabsorbed by active transport and diffusion ( aided by folding scales micro-villi)
Water also reabsorbed by osmosis
Some water(descending loop) and salts(ascending loop) are reabsorbed along the loop of henle
Describe secretion
H+ is secreted into the filtrate from blood
Describe the collecting ducts role in reabsorption
Any water which is not reabsorbed is transported via the collecting duct to ureter and transported back to the bladder. ADH can also act here
Why is the PCT , loop of henle and DCT surrounded by capillaries
Allows for reabsorption of substances into the blood
Secretion of substances from the blood
Desctibe how ADH in the kidneys after vigorous exercise
high salt conc detected by the hypothalamus of the brain.
sends a message to make ADH in the hypothalamus and the pituartry gland to secrete ADH.
ADH travels to the kidneys and increases the permeability of the nefron wall
large volume of water is reabsorbed by the nefrom back in the blood.
small voulme of concentrated urine produced.
what causes ADH to be produced in the hypothalamus
salty food/ vigouous exercise / low water intake
where is the site of action of ADH
Distial convoluted tuble and collecting duct
Ectoderm
outer germ layer from which the skin arises in embryo development
Ectotherm
a living organism obtains its heat from its enviorment surrounding and mannot maintain or regulate its own body temperture
endotherm
living organism that obtains its heat internally from respiration and can regulate its own body temperture
germ layer
single layer of cells
organ
a group of similar tissues working together to carry out a specific function
piloerection
erector muscle contracts and hair shaft stands up. this results in warm air being trapped close to the skin acting as an insulation layer.
Role of the skin
temperture regulation, protection, excretion, vitamin D produce by the epidermis by sunlight
Name the layers / features of skin
Adipose tissue
Hair follicle
Erector muscle
Hair shaft
Sebaceous gland
Nerves - attached to sense receptors
Sweat gland
Sweat duct
Sweat pore
Blood vessels
Dermis
Epidermis -(Malpighian layer (mitosis, melanin) granular layer (keratin added) conifers layer ( dead cells brushed away))
Name the three main layers and their function
Epidermis- protection, vitamin D production
Dermis- temperature regulation, nerve receptors
Adipose tissue- composed of lipids( energy storage and insulation)
Explain how skin is involved in temperature regulation when the individual is cold
Hypothalamus detects temperature drop
Piloerection is when the hair erector muscle contracts and causes hair to stand upright, trapping warm air close to the skin which acts as a insulation layer
Hypothalamus sends message to pituitary gland to increase blood the thyroxine produced by thyroid
Vasoconstriction blood vessels narrow, reducing heat loss from the skin( less blood passing through blood vessels)
Explain how skin is involved in temperature regulation when the individual is warm
Sweat glands secrete sweat and heat is lost as it evaporates.
Vasodilation- blood vessels get wider, increasing heat lost from the skin
Describe how the skin acts as protection
Epidermis is a waterproof barrier preventing entry of pathogens
Melanin protects skin from uv radiation
Sebaceous glands produces sebum oil. Stops skin from drying out and cracking, which is an entry point for pathogens
How does the skin act as an sense organ
Epidermis contains the receptors for pain, pressure and temperature
