Unit 4 Sheet Flashcards
(22 cards)
What is the purpose of the excretory system
Russ the body of metabolic wastes
Give 3 examples of wastes produced by body cells that must be removed
Bile pigments
Water
CO2
Bicarbonate
Ions-sodium, potassium, calcium, magnesium, iron
Nitrogenous wastes- ammonia, urea
What are 3 major organs of your body that make up the excretory system?
Kidneys- excrete urine
Skin- excretes perspiration (water salt small amounts of urea)
Liver- excretes bile
Lungs- excretes c02 and some water
What is the main organ of the excretory system
Kidney
Homeostasis
Maintaining internal balance. Referring to internal balance of water and salt and other waste products
Urea
Ammonia gets converted to urea in the liver. Urea is excreted by the kidney (in urine) and through the skin (perspiration)
Ureter
A muscular tube that moves urine from the kidneys to the bladder via peristalsis
Urinary bladder
The part of the body that stores urine until it is released from the body. Can expand and contract to hold between 300 and 1000ml of urine. Has stretch receptors that indicate when it is full and notify the brain
Nephron
Functional unit of the kidney filter wastes from the blood and retain water and other needed materials
Glomerulus
A cluster of capillaries where wastes are filtered from the blood
Bowman’s capsule
The cup like end of the nephron where water are forced out of the blood and into the nephron. Surrounds the glomerulus to catch the filtrate (urine) and send it into the proximal convoluted tubule
Loop of henle
À part of nephron that urine flows through. This is the place where urine becomes concentrated before it goes into the distal convoluted tubule
Urine
A liquid by-product of the body secreted by the kidneys through a process called urination m. Contains many byproducts, many rich in nitrogen, that require clearance from the bloodstream
Dialysis
The artificial process of eliminating waste and unwanted water from the blood. A person will be on dialysis if their kidneys cannot perform these functions on their own
Where in the nephron does filtration take place
Filtration takes places in the glomerulus
Blood pressure is so high that it forced small molecules such as water and nitrogenous wastes, nutrients, and ions from the glomerulus into bowman’s capsule where they become filtrate. Large molecules cannot pass into bowman’s capsule so they are filtered out via the efferent artériole
Where in the nephron does réabsorption take place
Réabsorption takes place in peritubular capillaries.
Molecules that are needed by the body are reabsorbed from the filtrate. These molecules move down the proximal convoluted tubule and into the peritubular capillary network where they are reabsorbed into the blood
Materials that don’t get reabsorbed continue through loop of henle. Urine becomes concentrated here. Water is reabsorbed. Salt is actively and passively reabsorbed
Where in the nephron does secretion take place
Secretion is when non -filterable wastes are added to the tubular fluid for secretion out in the urine. This takes places in the distal convoluted tubule. From here, fluid enters the collecting duct, it then enters the lerlcis of the kidney, then the ureters, then the bladder and lastly urethra
What 4 functions does kidneys perform that help with body homeostasis
- Regulate the volume of blood ph
- Help maintain blood ph
- Excrete urine
- Regulate the volume of salts
What is the effect of ingesting caffeine on the process of excretion
Caffeine increase glomerulus blood pressure then there will be more filtration. If caffeine inhibits réabsorption of sodium, then there will be more sodium and more water to be excreted. Therefore, you will urinate more often and your urine will be highly concentrated
What happens when you drink salty popcorn will large pop
Pop has caffeine. Caffeine is a diuretic which is something that makes you urinate more often. Caffeine inhibits réabsorption of sodium, therefore you will have more sodium and water to be excreted. However popcorn is salty and this increased sodium can be reabsorbed with the excess water that there is from the large pop( water follows the salt being reabsorbed) therefore, more popcorn has the potential to avoid having to pee
Why do we need to drink water
-maintain body’s fluid and electrolyte balance
- more water, more urine, more wastes that are excreted from our body
Desert organisms
-desert animals get water from food
To try to prevent it leaving their bodies they
- form burrows that do not get too hot or too cold and hold damp air inside
- thick outer converging on their skin to reduce moisture loss
-the kidneys concentrate urine so they excrete less water
- active at night when it’s cooler
