excretory system notes

science 10 review

diffusion-substances moving in and out of cells with the concentration gradient, h→l concentration

osmosis-movement of water across a semipermeable membrane with the concentration gradient

forced filtration-blood pressure forces materials across a  cell membrane

facilitated diffusion-diffusion aided with cell membrane proteins with concentration gradient.  Occurs more quickly than just diffusion

active transport-use cell proteins & ATP to move substances across cell membrane against the concentration gradient

bulk transport-cell membrane wraps around  clusters of molecules and forms vesicles inside the cell

how does bulk transport happen?

1. Twisting of the microtubules or “cytoskeleton” causes the membrane to surround the food particle.

2.  Particle becomes enclosed by the membrane and “pinches off” to form a vacuole.

3.  Food is then exposed to enzymes that break it down into useable molecules for cell metabolism.

• phagocytosis-food particles are engulfed, forms vesicle inside cell
• pinocytosis-fluids and dissolved particles are engulfed
• receptor mediated endocytosis-process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane'

^^what’s excreted by the skin:^^ & how:: releases thermal waste (heat energy)

• perspiration::excretes H2O & salt from the skin

^^what’s excreted by the nose & lungs & how::^^ it excretes gaseous waste when exhaled air excretes CO2 & H2O. The lungs excrete smaller molecules, which is why alcohol can be smelled. The nose excretes salts →mucus

^^what’s excreted by the digestive system & how::^^ solid waste is excreted through remaining materials from digestion. It’s egested by the large intestine

^^what’s excreted by the livers & how::^^toxic/poisonous waste is excreted. the liver removes urochrome. deanimation & converting ammonia into urea that’s released into blood & removed by kidneys. it overall detoxifies poisons/toxins in your blood stream.

• urochrome::yellow pigment making urine yellow. it’s a byproduct of hemoglobin breakdown
• deamination of proteins::removing amino groups (NH2) from AA. this results in ammonia (NH3) production & very toxic!
  • 2(NH3) + CO2 → [urea] CO(NH2)2 + H2O

^^what’s excreted by the urinary system & how::^^liquid waste is excreted. the systems is made of tissues/organs to filter, concentrate, store, & excrete urine

urinary excretory system

identify the primary tissues & organs in the urinary system

^^kidneys: function:^^1. remove wastes from blood(filtration) 2. maintain H2O balance in blood 3. maintain blood pH. produces urine

• what’s the most likely method for waste to get to the kidney before excretion:^^:^^ the blood

^^liver f^^::ingested toxins →soluble compounds for kidney elimination. hazardous protein products from metabolism→metabolites for kidney elimination. make uric acid waste product (form from breakdown nucleic acids) for kidney excretion

• how does the liver metabolise proteins::excess protein→carbs
• what do proteins have that carbs don’t:: nitrogen. ammonia is a toxic byproduct in deamination, so the liver ammonia→urea
• how is uric acid formed:: breakdown of nucleic acids. excreted by kidneys

^^blood f^^:: wastes travels through. aorta→renal arteries→kidneys (filter blood). blood→renal veins→body

^^ureters f^^:: connect urine from kidney→bladder. peristalsis transports urine

^^bladder f^^: sphincter @ base controls urine flow out of bladder→urethrea. stores urine

^^urethrea f^^: single tube onnects urine from bladder→exterior. urine out

Describe the direction of travel wastes take from your heart to the outside of your body, including all structures they pass through:: liver, heart (waste goes back to heart), aorta, renal arteries, rbcs along a + ra kidneys, ureters, bladder, urethra

kidney anatomy

^^renal cortex^^::outer layer of connective tissue that encircles the kidney

^^renal medulla^^::inner layer found beneath the cortex that ontains the salt gradient…

^^renal pelvis^^::area where the ureter joins the kidney. where urine is funneled towards the ureters from the medulla.

^^renal arteries^^:: blood away from heart→kidney

^^renal veins^^::blood from kidney & ureters →inferior vc

nephron::unit of the kidney that allows concentration of urine

• afferent arterioles::Small arteries that branch from the renal artery. They supply the nephrons with blood & travel towards the glomerulus
• glomerulus:: high pressure capillary bed surrounded by Bowman’s Capsule. blood filtration site.
• efferent arterioles:: away from glomerulus-→capillary net (vasa recta) that wraps around kidney tubules. substances removed due to filtration
• bowman’s capsule::A cap-like structure surrounding the glomerulus. receives the filtered fluids from the glomerulus b4 sending filtrate→PCT.
• PCT - Proximal Convoluted Tubule:: Carry filtrate from Bowman’s Capsule towards Loop of Henle. Secretion and Absorption of materials.
• loop of henle:: Divided into thick and thin sections, descending and ascending limbs. Crosses from the cortex→medulla and back→cortex. Water and Sodium movement take place here
• Distal Convoluted Tubule: Carry filtered fluids from Loop of Henle→collecting duct. Secretion and Absorption of materials
• vasa recta (capillary net)::Supply nutrients and oxygen→nephron. Absorption of water and solutes out of nephron
• collecting duct::carry urine from nephrons→renal pelvis→ureters→bladder→urethra

^^how does filtrate form urine in the nephrons:^^: 1. filtration: leaves blood & sends out most things 2.reabsorption: brings back important stuff 3.secretion:secrete toxic stuff & actively pump out urine

^^what occurs in the filtration of urine?^^::

@@filtration@@::high pressures forces solutes→BC (filtrate)

• high pressure in glomerulus forces solutes (glucose, salt, water, AA, H+, ammonia, urea)→BC=filtrate
• erythrocytes, wbcs, platelets, & larger plasma proteins are too large and stay in blood

^^what happens in the reabsorption of urine^^

@@reabsorption@@::selective transfer of essential solutes & water from the nephron tubules back→blood

• ^^given the molecules now in the filtrate, identify which are still needed by the body & can be returned to the blood plasma using the capillaries network^^:: hydrogen, AA, glucose, urea, water
• ^^what would happen if these substances remained in the filtrate^^:: substances wouldn’t be used since it’s immediately secreted. no nutrients=pass out

table on pg 10-11 \n

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