Summary Grade 11 the Excretory System ( The Kidney)

module 1 .
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fxcretorysystemm.am
excretory organs


kidneys
•
excrete all nitrogenous waste ( mostly urea )
• also excrete non -

nitrogenous waste :




excretion coz
-




-
water
-
ions
-
drugs
the body
-




removal of waste products from the

-
metabolic reactions all reactions taking place in the body
,


◦
cer tain waste products if accumulated can become

highly toxic lungs


.
coz released from cellular respiration
-

exhaled from lungs
homeostasis -


maintaining the internal environment of
'

steady
'
the body in a State so that cells c an


function properly
skin


•
H2O salt and urea released as sweat as water evaporates
liver ,
&
,
heat is lost body is cooled


-

not an excretory organ however many waste products
-
maintain temp
,

form here
-

Rid Of Waste




Nitrogenous waste

from excess amino acids
secretion : release of useful substances hormones
☆ urea formed ,
specialized the
-
main waste
from cells in
body
nitrogenous


☆ uric acid formed from breakdown of nucleic acid

colon
found muscle cells
☆ creatinine is in skeletal

formed from creatine phosphate
•
bite a cholestrol formed in liver -

small intestine


waste colon
Non -

Nitrogenous
egestion : removal of undigested a unabsorbed
food material ( faeces )
☆ toxins a drugs
-
painkillers nicotine
,




☆ at Chono /

permanent
causes damage main kidney
•




function of


other -
maintain homeostasis by controlling
☆ bile pigments composition a volume Of body fluid
breakdown of RBC
excrete nitrogenous waste to prevent
They :
☐

_ •




Cholesterol
toxic build up
☆

-
breakdown of bile salts
-
Responsible for OSMO regulation

◦
help maintain pH by excreting Ht

•
help maintain balance of ions by
reabsorbing or secreting them

, the urinary system kidneys
-




external structure :




function : maintain homeostasis by regulating
•

bean -
shaped
,
dark re d


the volume
-
and concentration of body fluids .
Inner border facing ver tebrae is concave = hilum

ureter vessels enter & exit
by filtering
a
-



and
.




reabsorbing materials from
the blood
•
tissue layers : -

Renal capsule of fibrous tissue

-
middle layer of adipose

homeostasis the
tendency of the body to seek
, _ outer layer of fibrous connective
✗ maintain a condition of balance or equilibrium tissue ( Renal fascia )
within its internal environment .




macroscopic structure
pyramid made up of
structure : inferior vena cava
,
car ries renal capsule collecting
,
ducts
,
deoxygenated blood to hear t
protects
papilla
a prevents tip of each
,
inte pyramid
Aor ta oxygenated blood Adrenal gland
µ
•Éf #
, ,
with nitrogenous waste secretes
-
cortex
to aldosterone nephron
body
( hormones )
↓ ↑ medulla
Renal artery # Made up of
,

carries Oz ✗
^ 8- ' 2
nitrogenous e Renal vein
,
carries
renal artery
waste to blood to vena in
Dynamics
blood
kidney cava
S Calyx
,
Renal vein a
shor t duct
purified collects
blood out from
kidneys ,
urine

titer nitrogenous waste collecting
out

Regulate
of blood

Hzo a salt ↓ ducts
pyramids
of



balance


ureter
↓ space
Renal sinus

between
,

ureter carries
calyces
,
urine to

motor nerve
,
_
bladder
↓ Renal pelvis
stimulate ,
contrac tion of urine drains from
bladder wall calyces into this
bladder stores a re a of
, ureter
urine




sphincter 1 urethra
,
carries
muscle controls flow urine to exterior
,
of urine


aldosterone

↑
• Adrenal glands endocrine glands ✗ release ADH which
,
regulates sal t concentration in
body