Homeostasis Flashcards
what is homeostasis? examples? why do we need it?
the maintenance of the internal conditions of body at equilibrium, despite changes in the external environment.
For example:
* the core temp. of human body remains at about 37°C despite fluctuations in the surrounding air temp.
* the blood glucose level remains about 1g per litre despite eating a meal rich in carbs
important for the efficient functioning of enzymes.
osmoregulation is the _______ of homeostasis? name others?
what is waste products? aka
what is excretion?
process Thermoregulation Excretion
any material that is produced during body metabolism & that may harm the body.
process in which metabolic wastes are eliminated from body to maintain the internal conditions at equilibrium.
metabolic waste
what is osmoregulation?
what is the diff. b/w osmoregulation & thermoregulation?
Osmoregulation: It is regulation of the conc. of water & salts in body fluids (i.e. blood and tissue fluids).
Thermoregulation: The maintenance of internal body temperature.
FMIGTN
why is thermoregulation important?
- The enzymes of body work best at particular temperatures (optimum temp.). Any change in body temp. may affect the functioning of enzymes.
how is CO2 removed by plants?
what causes surplus CO2 to build up?
It is removed from the tissue cells by diffusion.
* In leaves & young stems, CO2 escapes out through stomata.
* In young roots, CO2 diffuses through the general root surface, especially through root hairs.
1. In daytime, the CO2 produced during cellular respiration is utilized in photosynthesis & hence it is not a waste product.
2. At night, it is surplus because there is no utilization of CO2. (no photsynthesis)
just understand and learn this
where is oxygen produced?
what happens after that?
Oxygen is produced in mesophyll cells only during daytime, as a by-product of photosynthesis.
After its utilization in cellular respiration, the leaf cells remove the extra amount of oxygen through stomata.
how is extra water removed in plants? why transpiration doesn’t take place at night?
by guttation or transpiration
The appearance of drops of water on the tips or edges of leaves is called guttation.
hydathodes
At night, transpiration usually doesn’t occur cz most plants have their stomata closed.
how are metabolic waste removed in plants?
The _____________ is a secondary function of leaf fall. what if not shed?
pg 18
the calcium oxalate just remains as harmless crystals in the leaves
removal of excretory products
name other waste produced by plants?
pg 18
latex
what are hydrophytes?
what charcteristics do they have for their habitat?
example?
Hydrophytes are the plants which live completely or partially submerged in freshwater.
Such plants do not face the problem of water shortage. They have developed mechanisms for the removal of extra water from their cells.
* Hydrophytes have broad leaves with a large number of stomata on their upper surfaces. This characteristic helps them to remove the extra amount of water.
* water lily & lotus
what are xerophytes?
what charcteristics do they have for their habitat?
example?
Xerophytes live in dry environments.
1. They possess thick, waxy cuticle over their epidermis to reduce water loss from internal tissues.
2. They have less number of stomata to reduce the rate of transpiration.
3. Such plants have deep roots to absorb maximum water from soil.
4. Some xerophytes have special parenchyma cells in stems or roots in which they store large quantities of water. This makes their stems or roots wet and juicy, called succulent organs.
* Cacti, aloe vera, pineapple
what are halophytes?
how do they maintain water inside if they live in salty environments?
example?
Halophytes are plants growing in areas of high salinity.
Many sea grasses & mangroves
FMIGTN
xero hydro halo phytes are types of _______ on the basis of ______.
plants
the available amount of water & salts
how many layers does skin have?
function of skin?
benefits of sweat?
skin consists of 2 layers.
plays imp. role in the regulation of body temp.
* Metabolic wastes such as excess water, salts, urea & uric acid are removed in sweat.
what happens in cold weather?
how is the body temp. regulated?
- The thin layer of fat cells in the dermis insulates the body.
- Hair raised by the arrector pili muscles result in goosebumps formation. It creates an insulating blanket of warm air.
- the blood vessels in the skin constrict. And less heat is lost to the body.
FMIGTN
what happens in warm weather? skin?
how do lungs keep CO2 conc. in blood in normal range? in short
how is CO2 produced?
pg 20
explain the process of urinary system in short?
Kidneys filter blood to produce urine & the ureters carry urine from kidneys to urinary bladder. The bladder temporarily stores urine until it is released from body. Urethra is the tube that carries urine from urinary bladder to the outside of body
1 pair of kidneys, a pair of ureters, a urinary bladder and a urethra.
What is the shape & color of the kidneys? Why
What is the weight of each kidney?
Which kidney is positioned higher in the body?
what are the functions of kidney?
- Kidneys are dark-red & bean-shaped.
- Each kidney weighs about 120 grams.
- The left kidney is positioned a little higher than the right kidney.
Where are the kidneys located in the body?
What protects the kidneys?
the _____ side of kidney faces ver?
Kidney receive blood from and to?
They are placed against the back wall of abdominal cavity just below diaphragm, one on either side of vertebral column.
They are protected by the last 2 ribs.
concave vertebral column
what is hilus?
What structures pass through the concave side of the kidney?
from where does kidney receive blood?
- a depression near the centre of the concave area of kidney.
- The ureter, blood vessels, lymphatic vessels, & nerves.
- from the dorsal aorta via renal arteries
What are the main regions visible in the longitudinal section of the kidney?
What is the outer part of the kidney called and what is its color?
What is the base of the ureter called?
Q: What is the inner part of the kidney called and what is its color?
Q: What structures make up the renal medulla?
Q: Where do the renal pyramids project into?
A: The renal cortex & the renal medulla.
A: The outer part is renal cortex, & it is dark red in color.
A: renal pelvis.
A: The inner part is called the renal medulla, and it is pale red in color.
A: The renal medulla consists of several cone-shaped areas called renal pyramids.
A: The renal pyramids project into a funnel-shaped cavity called the renal pelvis.
Q: what is nephron?
Q: How many nephrons are there in each kidney?
Q: What are the main parts of a nephron?
Q: What are the parts of the renal corpuscle?
Q: What is the glomerulus?
Many collecting ducts join together to form
____________ which drain into _________.
A: the functional unit of kidneys
A: There are over 1M nephrons in each kidney.
A: The renal corpuscle & the renal tubule.
A: The glomerulus & Bowman’s capsule.
A: The glomerulus is a network of capillaries.
several hundred papillary ducts renal pelvis
Q: What is Bowman’s capsule?
Q: What are the parts of the renal tubule, in order?
Q: Where do the distal convoluted tubules of many nephrons open into?
The __________ is the part of nephron which starts after Bowman’s capsule
A: a cup-shaped structure that encloses the glomerulus.
A: The proximal convoluted tubule, the Loop of Henle, and the distal convoluted tubule.
A: They open into a single collecting duct, which then joins with others to form papillary ducts that drain into the renal pelvis.
renal tubule
go to notion and label the diagram of nephron and kidney?
name the structure that is involved in
filtration
re absorption
tubular secretion
glomerulus
PCT & LOH
DCT & collecting duct
Q: What is the first step in urine formation?
Q: Where does blood enter the kidney?
Q: Main function of kidney?
Q: urine formation takes place in ____ steps.
Q: where is glucose reabsorbed in the kidneys?
A: Pressure filtration.
A: Via the renal artery.
A: urine formation
A: 3
A: most of the glucose is reabsorbed from the proximal convoluted tubule.
what happens in pressure filtration?
When blood enters the kidney via the renal artery, it goes to many arterioles, and then to the glomerulus. The pressure of blood is very high & so most of the water,salts, glucose & urea of blood is forced out of glomerular capillaries. This material passes into the Bowman’s capsule and is now called glomerular filtrate.
Q: What is the second step in urine formation?
Q: What role does the Loop of Henle play in selective re-absorption?
Q: What occurs in the distal convoluted tubule during selective re-absorption?
Q: Why is tubular secretion important?
A: selective reabsorption
A: The descending limb of the Loop of Henle allows the reabsorption of water, while the ascending limb allows the reabsorption of salts.
A: The distal convoluted tubule allows the reabsorption of additional water into the blood.
A: to maintain blood at a normal pH.
Q: What is selective re-absorption in the kidneys?
Q: What is tubular secretion in the kidneys?
A: the process where about 99% of the glomerular filtrate is reabsorbed into the blood capillaries surrounding the renal tubule through osmosis, diffusion, and active transport.
A: the process where different ions, creatinine, urea, etc., are secreted from the blood into the filtrate in the renal tubule to maintain a normal blood pH.
where is water reabsorbed in the kidneys?
Proximal convoluted tubule: some water is reabsorbed from the proximal convoluted tubule. Here, salts are reabsorbed by active transport & then water follows by osmosis.
loop of Henle: the descending limb of loop of Henle allows the reabsorption of water.
Distal convoluted tubule: again allows the reabsorption of water into the blood.
where is salt reabsorbed in the kidneys?
which organ in the body plays imp. role in osmoregulation?
What causes the material to move from glomerular capillaries to Bowman’s capsule?
Proximal convoluted tubule: Here, salts are reabsorbed by active transport and then water follows by osmosis.
loop of Henle: the ascending limb of Loop of Henle allows the reabsorption of salts.
kidneys
Blood pressure
label the diagram of nephron in terms of urine formation.
what happens when there is excess water in body fluids?
A: kidneys filter more water from glomerular capillaries into Bowman’s capsule. Similarly less water is reabsorbed & abundant dilute urine is produced. It brings down the volume of body fluids to normal.
how kidney helps to overcome the problem of dehydration.
This whole process is under ________ control.
what is the thirst centre?
kidneys filter less water from glomerular capillaries and the rate of reabsorption of water is increased. Less filtration and more reabsorption produce small amount of concentrated (hypertonic) urine. It increases the volume of body fluids to normal.
hormonal
hypothalamus
How do kidney stones form?
pg 24
Where do most kidney stones start, and where can they travel?
what happens if kidney stones passes to the ureter?
How can most kidney stones pass through the urinary system? how can kidney stones be removed?
Most kidney stones start in the kidney. Some may travel to the ureter or the urinary bladder.
may stimulate severe pain in the kidney….
About 90% of kidney stones can pass by drinking plenty of water.
by surgery or lithptripsy
write the movement of a molecule of urea from blood to urethra?
pg 24
what is lithotripsy?
What are the treatments for kidney failure?
Lithotripsy uses non-electrical shock waves from outside to break stones into sand-like particles that pass through urine.
dialysis & kidney transplant.
What is kidney failure?
What are the leading causes of kidney failure?
Kidney failure means a complete or partial failure of kidneys to function.
The leading causes of kidney failure are diabetes mellitus & hypertension. Sudden interruption in the blood supply to the kidney and drug overdoses can also cause kidney failure.
renal artery
renal vein?
-
Renal Artery: Carries oxygen-rich blood with waste to the kidneys for filtering.
red -
Renal Vein: Carries clean, oxygen-poor blood away from the kidneys back to the heart.
blue
renal vein blue very blue v b vein blue
“A” for arriving “V” for vanishing
what is dialysis?
peritoneal cavity is lined by ________.
function of liver?
Dialysis means the cleaning of blood by artificial ways. There are two methods of dialysis.
peritoneum
What is the role of the peritoneum in peritoneal dialysis?
Peritoneal dialysis
Pg 26
what is haemodialysis?
what is dialyzer?
how is blood cleaned?
- In haemodialysis, patient’s blood is pumped through an apparatus called dialyzer.
- The dialyzer contains long tubes, the walls of which act as semi-permeable membranes
- Blood flows through the tubes while the dialysis fluid flows around the tubes. Extra water & wastes move from blood into the dialysis fluid. The cleansed blood is then returned back to body
What is kidney transplantation?
Who can donate a kidney for transplantation?
What is the average lifetime of a donated kidney?
What if kidney is not matching?
- the replacement of a patient’s damaged kidney with a healthy donor kidney.
- A kidney may be donated by a deceased donor or a living donor, who may or may not be a relative of the patient.
- ten to fifteen years.
- connected to the patient’s blood and urinary system.
