Name: ______Date: ______

Excretion Notes

Functions:

  • Removal of metabolic wastes from the body
  • Metabolic wastes are wastes that our cells have created through chemical reactions (EX: Cellular Respiration creates carbon dioxide that we need to get rid of)
  • Main wastes our excretory system removes:
  • Carbon Dioxide
  • Excess Water (too much water will disrupt osmosis)
  • Salt (will disrupt diffusion)
  • Heat (so our enzymes function properly)
  • Urea (created when we digest proteins, toxic)

Main Organs Involved in Excretion:

  • Lungs – remove carbon dioxide from the body through respiration
  • Skin – removes urea, salt, and excess water through sweat
  • Kidneys – remove urine (urea, salt, and excess water) through urination

Skin:

  • The skin has two layers
  • Dermis – lower layer of skin that is made up of cells, sweat glands, sebaceous glands, blood vessels and nerves
  • Epidermis – upper layer of skin covered in dead skin cells and live replicating cells below those

Epidermis:

  • Functions
  • Prevent Water Loss
  • Prevent absorption of unwanted materials
  • Protect cells contained by the skin
  • Keep dividing to keep up with the number of cells lost via friction (your skin touching other things)
  • Epidermis has four layers
  • Stratum corneum – top most layer composed of dead skin cells that protect the cells below it
  • Stratum granulosum – this layer of cells is about to die and become the next layer. The cells are full of granules that will keratinize to offer our skin the protection it needs
  • Stratum spinosum – This layer is full of lipids that reduce water loss from the skin
  • Stratum basale – the cells in this layer are constantly dividing to provide the above layers with new cells.

Dermis:

  • Functions:
  • Cool the body
  • Send sensory information about pressure and heat
  • Sweat Glands:
  • Sweat glands are located all over the skin except on lips and nipples.
  • They consist are essentially a ball of tubing which straightens and extend to the surface of the skin creating a pore
  • The purpose of the sweat gland it tocool the body when it is too hot
  • Some sweat glands excrete an odor as well as sweat. These are mostly concentrated in the arm pits and genital region
  • Capillaries:
  • The capillaries in the dermis supply the sweat gland with the fluid and wastes to make sweat
  • The provide oxygen and nutrients to the dividing cells in the basal layer of skin cells and to the nerves and hair follicles in the dermis
  • Hair Follicles:
  • A sac of cells that creates hair and which the sebaceous (oil) gland is connected
  • The base that is enriched with capillaries is the only living part of the hair
  • Hair is important because it is attached to nerves which send sensory information about how the hair moves
  • It also helps prevent air from stealing our warmth
  • Nerves:
  • Sense pressure and hot or cold

Urinary System:

Kidneys:

  • A large artery called the renal artery flows into the kidney and divides into tiny capillaries
  • The capillaries join nephrons which makes up the kidneys where wastes such as urea and salt are filtered out
  • Then the newly filtered blood leaves through the renal vain to travel back to the heart
  • The waste materials flow into the ureter
  • The inner portion of the kidney is the medula and the outer layer is the cortex

Nephrons:

  • The capillaries form a ball called the glomerulus which is surrounded by the Bowman’s capsule
  • The Bowman’s Capsule thins out and forms a loop (Loop of Henle)
  • The capillaries go around the loop and as the loop descends the concentration changes pulling more urea out of the blood via diffusion

Ureter:

  • The wastes (salt and urea) pulled from the blood by the Loop of Henle travel to the collecting duct, which leads to the Ureter
  • The ureter is the tube that urine (composed of urea, salt, and water) travels down from the kidneys to the bladder

Urinary Bladder:

  • The bladder is a large muscular sac that holds the urine until there is enough to pass out of the body
  • The bladder is flexible and expands with increase urine and contracts to push theurine out of the bodythrough the urethra

Urethra:

  • This is the tube that connects the bladder to the outside of the body
  • In men it has a smaller diameter and is much longer than in women

Excretory Diseases:

  • Kidney stones – build up of minerals inside the kidneys until those minerals form a stone
  • Urinary Tract Infections – bacterial infection of the urethra and bladder causing irritation and bleeding
  • Kidney Disease – when the nephrons in the kidney start to die and stop filtering the blood
  • Gout – a build up of uric acid in the blood
  • Boils – a bacterial infection of the sweat gland causing it to swell and become very uncomfortable

Name: ______Date: ______

Excretion Notes

Functions:

  • Removal of ______wastes from the body
  • Metabolic wastes are wastes that our ______have created through chemical ______(EX: Cellular ______creates ______that we need to get rid of)
  • Main wastes our excretory system removes:
  • Carbon Dioxide
  • Excess ______(too much water will disrupt ______)
  • Salt (will disrupt ______)
  • ______(so our enzymes function properly)
  • Urea (created when we digest ______, toxic)

Main Organs Involved in Excretion:

  • Lungs – remove ______from the body through ______
  • Skin – removes ______, salt, and excess ______through ______
  • Kidneys – remove ______(urea, ______, and excess water) through filtration and urination

Skin:

  • The skin has ______layers
  • Dermis – ______layer of skin that is made up of cells, sweat ______,______glands, blood vessels and nerves
  • ______– upper layer of skin covered in ______skin cells and live replicating cells below those

Epidermis:

  • Functions
  • Prevent ______Loss
  • ______absorption of unwanted materials
  • ______cells contained by the skin
  • Keep dividing to keep up with the number of cells lost via ______
  • Epidermis has four layers
  • Stratum corneum – ______most layer composed of ______skin cells that ______the cells below it
  • Stratum granulosum – this layer of cells is about to ______and become the next layer. The cells are full of granules that will ______to offer our skin the protection it needs
  • Stratum spinosum – This layer is full of ______that reduce water loss from the skin
  • Stratum basale – the cells in this layer are constantly ______to provide the above layers with ______cells.

Dermis:

  • Functions:
  • ______the body
  • Send ______information about ______and ______
  • Sweat Glands:
  • Sweat glands are located all over the skin except on ______and ______.
  • They are essentially a ball of ______which straightens and extend to the surface of the skin creating a ______
  • The purpose of the sweat gland it to______the body when it is too ______
  • Some sweat glands excrete an ______as well as sweat. These are mostly concentrated in the ______and ______region
  • Capillaries:
  • The capillaries in the ______supply the ______gland with the ______and wastes to make sweat
  • The provide ______and ______to the dividing cells in the basal layer of ______cells and to the nerves and ______follicles in the dermis
  • Hair Follicles:
  • A sac of ______that creates hair and which the sebaceous (______) gland is connected
  • The ______that is enriched with ______is the only ______part of the hair
  • Hair is important because it is attached to ______which send sensory information about how the hair ______
  • It also helps prevent ______from stealing our ______
  • Nerves:
  • Sense ______and hot or ______

Urinary System:

Kidneys:

  • A large artery called the ______artery flows into the ______and divides into tiny ______
  • The capillaries join ______which makes up the kidneys where ______such as ______and ______are filtered out
  • Then the newly ______blood leaves through the renal vain to travel back to the heart
  • The waste materials flow into the ______
  • The inner portion of the kidney is the ______and the outer layer is the ______

Nephrons:

  • The capillaries form a ______called the ______which is surrounded by the ______capsule
  • The Bowman’s Capsule thins out and forms a ______(Loop of ______)
  • The ______go around the loop and as the loop descends the ______changes pulling more urea out of the ______via ______

Ureter:

  • The wastes (______and ______) pulled from the blood by the ______of ______travel to the ______, which leads to the ureter
  • The ureter is the ______that urine (composed of urea, salt, and water) travels down from the ______to the ______

Urinary Bladder:

  • The bladder is a large ______sac that holds the ______until there is enough to pass out of the body
  • The bladder is ______and expands with increasing urine and ______to push theurine out of the bodythrough the ______

Urethra:

  • This is the tube that connects the ______to the ______of the body
  • In men it has a smaller ______and is much ______than in women

Excretory Diseases:

  • Kidney ______– build up of ______inside the kidneys until those minerals form a stone
  • ______Tract Infections – ______infection of the ______and ______causing irritation and bleeding
  • Kidney Disease – when the ______in the kidney start to ______and stop ______the blood
  • Gout – a build up of ______in the blood
  • Boils – a bacterial ______of the ______gland causing it to swell and become very uncomfortable