Name: _____________________________________ Date: _________________________

Excretion NotesFunctions:

o 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)o 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:o Lungs – remove carbon dioxide from the body through respirationo Skin – removes urea, salt, and excess water through sweato Kidneys – remove urine (urea, salt, and excess water) through urination

Skin:o 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:o 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)o 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:o Functions:

Cool the body Send sensory information about pressure and heat

o 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 to cool 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

o 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 dermiso 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

o Nerves: Sense pressure and hot or cold

Urinary System:

Kidneys:o A large artery called the renal artery flows into the kidney and divides into tiny capillarieso The capillaries join nephrons which makes up the kidneys where wastes such as urea and salt are filtered

outo Then the newly filtered blood leaves through the renal vain to travel back to the hearto The waste materials flow into the ureter o The inner portion of the kidney is the medula and the outer layer is the cortex

Nephrons:o The capillaries form a ball called the glomerulus

which is surrounded by the Bowman’s capsuleo The Bowman’s Capsule thins out and forms a loop

(Loop of Henle)o The capillaries go around the loop and as the loop

descends the concentration changes pulling more urea out of the blood via diffusion

Ureter:o The wastes (salt and urea) pulled from the blood by

the Loop of Henle travel to the collecting duct, which leads to the Ureter

o The ureter is the tube that urine (composed of urea, salt, and water) travels down from the kidneys to the bladder

Urinary Bladder:o The bladder is a large muscular sac that holds the

urine until there is enough to pass out of the bodyo The bladder is flexible and expands with increase

urine and contracts to push the urine out of the body through the urethra

Urethra:

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

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

Name: _____________________________________ Date: _________________________

Excretion NotesFunctions:

o 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)

o 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:

o Lungs – remove ___________________ _______________________ from the body through

_____________________

o Skin – removes ______________, salt, and excess __________________ through ________________

o Kidneys – remove __________________ (urea, ___________, and excess water) through filtration and

urination

Skin:

o 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:

o Functions

Prevent _____________________ Loss

___________________ absorption of unwanted materials

_____________________ cells contained by the skin

Keep dividing to keep up with the number of cells lost via ____________________

o 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:

o Functions:

_______________ the body

Send ______________________ information about ____________________ and ___________

o 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

o 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

o 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 ___________________

o Nerves:

Sense _______________________ and hot or ________________

Urinary System:

Kidneys:

o A large artery called the ________________ artery flows into the __________________ and divides

into tiny _________________________

o The capillaries join _______________________ which makes up the kidneys where ______________

such as __________ and ____________ are filtered out

o Then the newly ___________________ blood leaves

through the renal vain to travel back to the heart

o The waste materials flow into the _________________

o The inner portion of the kidney is the _______________ and

the outer layer is the _________________

Nephrons:

o The capillaries form a ____________ called the

______________________ which is surrounded by the

______________________ capsule

o The Bowman’s Capsule thins out and forms a

______________ (Loop of ________________)

o The _____________________ go around the loop and as the

loop descends the _______________________ changes

pulling more urea out of the _________________ via

_________________________

Ureter:

o The wastes (___________ and _____________) pulled from the blood by the _______________ of

________________ travel to the ________________________ _____________, which leads to the

ureter

o The ureter is the ______________ that urine (composed of urea, salt, and water) travels down from the

_____________________ to the ___________________

Urinary Bladder:

o The bladder is a large ____________________ sac that holds the _______________ until there is

enough to pass out of the body

o The bladder is _____________________ and expands with increasing urine and ___________________

to push the urine out of the body through the _____________________

Urethra:

o This is the tube that connects the ___________________ to the ______________________ of the body

o In men it has a smaller _____________________ and is much ____________________ than in women

Excretory Diseases:

o Kidney __________________ – build up of ____________________ inside the kidneys until those

minerals form a stone

o __________________ Tract Infections – ____________________ infection of the _________________

and ___________________ causing irritation and bleeding

o Kidney Disease – when the _____________________ in the kidney start to _________ and stop

______________________ the blood

o Gout – a build up of ______________ _______________ in the blood

o Boils – a bacterial _______________________ of the _______________ gland causing it to swell and

become very uncomfortable