Location and Functions of Key
Structures
1. Excretory System
S. Structure Location Function
No.
1 Kidney/Nephron Lie along the posterior abdominal wall, Excretion of Nitrogenous wastes
one on either side of the vertebral like urea. Osmoregulation.
column.
2 Ureters They arise from the renal pelvis of the Transports urine from the pelvis of
kidneys at the hilum and the other end the kidney to the urinary bladder.
opens into the urinary bladder.
3 Urinary bladder Sac like structure situated in the lower Temporary storage of urine.
end of the abdomen into which the
other end of the ureter opens.
4 Urethra Short, muscular tube arising from the Allows the passage of urine from
neck of the urinary bladder and leading urinary bladder to outside the
to the outside. body.
5 Glomerulus Knot of capillaries present in the cup of Brings about ultrafiltration.
the Bowman's capsule.
6 Proximal convoluted Lies in the cortex of the kidney. Reabsorbs water, glucose and
tubule sodium and chloride ions from
glomerular filtrate into renal
capillaries.
7 Loop of Henle Present in the renal medulla. Reabsorption of water and sodium
ions from glomerular filtrate to
renal capillaries.
8 Distal convoluted Present in the cortex of the kidney. Tubular secretion of K+, Creatinine
tubule and foreign substances like
antibiotics into urine.
9 Collecting duct Formed by the union of collecting Transports urine from nephron to
tubules, passes through the cortex, the pelvis of the kidney.
medulla and opens into the pelvis of the
kidney.
, 2. Circulatory System
S. Structure Location Function
No.
1 Heart Situated between the two lungs in the Pumps oxygenated blood from
thoracic cavity. The apex is tilted lungs to the different parts of the
towards the left side. body. Pumps deoxygenated blood
from parts of body to lungs for
oxygenation.
2 Pericardial fluid Found in the pericardial cavity, Protects the heart from mechanical
between the two membranes of the injury and shock. Acts as a
pericardium. lubricant and reduces friction for
the beating of the heart.
3 Sino atrial node Upper wall of right atrium close to the Initiates and regulates the heart
(SA node) or opening of the vena cava. beat. Receives impulse from
Pacemaker medulla oblongata and regulates
the contraction of the auricles.
4 Atrio Ventricular Bottom of the right auricle near the Regulates the contraction of the
node (AV node) tricuspid valve. ventricles.
5 Bundle of His Arises from the AV node and extends It receives an impulse from the AV
to the interventricular septum. node and transmits it to the
Purkinje fibres.
6 Bicuspid valve or Between the left auricle and ventricle Prevents the backflow of blood
mitral valve of the heart. from the left ventricle to the left
auricle.
7 Tricuspid valve Between the right auricle and ventricle Prevents the backflow of blood
of the heart. from the right ventricle to the right
auricle.
8 Chordae tendinae Extend from the papillary muscles to Keeps the tricuspid and bicuspid
the pointed ends of the cuspid valves. valves in position and prevents
them from upturning into the
auricles.
9 Pulmonary At the opening of the pulmonary Prevents backflow of
semilunar valve artery which arises from the right deoxygenated blood from the
ventricle. pulmonary artery into the right
ventricle.
10 Aortic semilunar At the opening of the aorta which Prevents backflow of oxygenated
valve arises from the left ventricle. blood from the aorta into the left
Structures
1. Excretory System
S. Structure Location Function
No.
1 Kidney/Nephron Lie along the posterior abdominal wall, Excretion of Nitrogenous wastes
one on either side of the vertebral like urea. Osmoregulation.
column.
2 Ureters They arise from the renal pelvis of the Transports urine from the pelvis of
kidneys at the hilum and the other end the kidney to the urinary bladder.
opens into the urinary bladder.
3 Urinary bladder Sac like structure situated in the lower Temporary storage of urine.
end of the abdomen into which the
other end of the ureter opens.
4 Urethra Short, muscular tube arising from the Allows the passage of urine from
neck of the urinary bladder and leading urinary bladder to outside the
to the outside. body.
5 Glomerulus Knot of capillaries present in the cup of Brings about ultrafiltration.
the Bowman's capsule.
6 Proximal convoluted Lies in the cortex of the kidney. Reabsorbs water, glucose and
tubule sodium and chloride ions from
glomerular filtrate into renal
capillaries.
7 Loop of Henle Present in the renal medulla. Reabsorption of water and sodium
ions from glomerular filtrate to
renal capillaries.
8 Distal convoluted Present in the cortex of the kidney. Tubular secretion of K+, Creatinine
tubule and foreign substances like
antibiotics into urine.
9 Collecting duct Formed by the union of collecting Transports urine from nephron to
tubules, passes through the cortex, the pelvis of the kidney.
medulla and opens into the pelvis of the
kidney.
, 2. Circulatory System
S. Structure Location Function
No.
1 Heart Situated between the two lungs in the Pumps oxygenated blood from
thoracic cavity. The apex is tilted lungs to the different parts of the
towards the left side. body. Pumps deoxygenated blood
from parts of body to lungs for
oxygenation.
2 Pericardial fluid Found in the pericardial cavity, Protects the heart from mechanical
between the two membranes of the injury and shock. Acts as a
pericardium. lubricant and reduces friction for
the beating of the heart.
3 Sino atrial node Upper wall of right atrium close to the Initiates and regulates the heart
(SA node) or opening of the vena cava. beat. Receives impulse from
Pacemaker medulla oblongata and regulates
the contraction of the auricles.
4 Atrio Ventricular Bottom of the right auricle near the Regulates the contraction of the
node (AV node) tricuspid valve. ventricles.
5 Bundle of His Arises from the AV node and extends It receives an impulse from the AV
to the interventricular septum. node and transmits it to the
Purkinje fibres.
6 Bicuspid valve or Between the left auricle and ventricle Prevents the backflow of blood
mitral valve of the heart. from the left ventricle to the left
auricle.
7 Tricuspid valve Between the right auricle and ventricle Prevents the backflow of blood
of the heart. from the right ventricle to the right
auricle.
8 Chordae tendinae Extend from the papillary muscles to Keeps the tricuspid and bicuspid
the pointed ends of the cuspid valves. valves in position and prevents
them from upturning into the
auricles.
9 Pulmonary At the opening of the pulmonary Prevents backflow of
semilunar valve artery which arises from the right deoxygenated blood from the
ventricle. pulmonary artery into the right
ventricle.
10 Aortic semilunar At the opening of the aorta which Prevents backflow of oxygenated
valve arises from the left ventricle. blood from the aorta into the left
