Biology 12 - Circulatory System
Umbilicial arteries and veins
Vessels that travel and form the placenta
Where does the blood pumped related with the arterial duct go?
Will be directed to the lungs and into the aorta
How does the artery travel across the placenta?
With waste
Where is the venous duct located?
Attaches at the babies liver but bypasses the liver
Where do interstitial fluid go?
Back into the body through capillary membrane but most enter lymphatic capillaries to become lymph
Interstital fluid
Bits of blood and other body liquids that collect in the spaces between cells
How is blood pumped in the systemic circuit?
Blood is pumped to the tissues and organs by the left ventricle of the heart
What do the veins act as?
Blood reservoirs
Right side pumps...
Blood to the lungs
Venules function
Drains blood from the capillaries and then join to form a vein
Thoraic duct
Drains the rest of the body and drains into the left subclavian vein
Aterial duct also known as...
Ductus arteriosus
Venous Duct is also known as...
Ductus venosus
How can babies be affected by what mothers ingest
Due to the venous duct
Purpose of the Arteries thick elastic walls
For it to stretch
How are Lymphs formed?
From interstital fluid
Vein travels....
From placenta to fetus with blood rich in oxygen and nutrients
What does Lymph resemble?
Plasma but it is more diluted
What does flow depend on in the Lymphatic system?
Pressure from the blood system and massaging effect of the muscles
Valves function
Prevents backflow of blood then they are closed and allows for blood to move in a certain direction
Heart function
Pump that circulates the blood throughout the body
Renal vein
Returns blood from kidneys to posterior vena cava
Subclavian Vein
Returns blood from the arms to anterior vena cava
Iliac veins
Returns blood from the legs to posterior vena cava
Hepatic vein
Returns blood from the liver to the posterior vena cava
How is the pulmonary circuit powered?
Right ventricle of the heart
Lymph nodes physical appearance
Small oval or round structures that occur along strategic places on lymph vessels
What are Capillaries?
Small vessels that are the branches of the aterioles
What is pumped through the Oval Opening?
Some blood from the right atrium therefore pumped through and into the left atrium, bypassing the pulmonary circuit
In a capillary bed some, many or most of these....
Sphincter muscles may be closed off so that less ormore blood flow to the area as needed
Lacteal
-Blind ends of lymph vessels in villi of the small intestine -Products of fat digestion enter here
Function of the circulatory system (2)
-Bring nutrients to the cells -Take wastes away from the cells
What does the lymph also pick up? (Beside from interstital fluid) And why?
-Cell debris -Fat globules They are too big to be absorbed through capillary membrane
Fighting Infection (Lymphocyte function)
-Cleansing lymph -Produce lymphocytes -Some lymphocytes produce antibodies
Right Lymphatic Duct
-Drains the upper upper portion of the body and empties into the right subclavian vein
Differences between fetal and adult circulation
-Fetal lungs are not used to provide oxygen -Fetus must get all its nutrients and dump waste through the mother
Arteries description
-Large -Thick elastic walls - Surrounded by smooth muscle to control the diameter of the artery
Aorta
-Largest artery -Takes blood to all major body regions and organs from the left ventricle
Superior or Anterior Vena Cava
-Largest vein -Collects blood from jugular and subclavian veins
Posterior or Inferior Vena cava
-Largest vein -Collects blood from lower body
Spleen
-Located behind the stomach -Contains white blood cells and stores blood
Thymus Gland
-Located in the upper thoraic cavity -Functions in production and maturation of some lymphocytes -Decrease in size with age
Heart 3 tissue layers
-Pericaridum -Myocardial -Endothelial
2 circuits of the Cardiovascular system
-Pulmonary circuit -Systemic circuit
Two main trunks of the Lymphatic vessels
-Right Lymphatic Duct -Thoraic duct
Capillaries function
-They connect the arterioles to venules -Exchange material with tissues
Lymph nodes function
-They produce and store lymphocytes
Main functions of Lymphatic system
-Transport of excess tissue fluid back to the cardiovascular system -Absorption of fat from the intestine and transport to blood -Fight infection
5 types of blood vessels
-Vein -Arteries -Capillaries -Arteries Artery
Description of Capillaries
-Very narrow microscopic tubes -The walls of these tubes are one layer thick
Veins Description
-Walls are thinner than arterial walls -Has valves
How big are aterioles?
0.2 mm in diamter or smaller
Arteries contain about (%) of body's blood
20
When does the fetal heart develop?
3-4 weeks into the pregnancy
Capillaries contain about (%) of body's blood
5
Veins contain about (%) of body's blood
75
What does the Lymph not have?
A pump of its own
Similar thing between the arterial duct and the oval opening
Both have the function to bypass the pulmonary circuit
Pulmonary vein
Brings oxygenated blood to the left atrium from the lungs
Veins and venules function
Carry blood from the tissues to the heart
Lymph capillaries take up...
Cell fluids
What does the Lymphatic system ultimately do?
Connects back with the cardiovascular system because the fluid from the lymphatic system eventually gets sent back to the bloodstream
Hepatic portal vein
Connects blood vessels to the villi to the liver, carries nutrient rich blood to liver for processing
Arterial duct function
Connects pulmonary artery and aorta
Venous duct function
Connects umbilical vein to the vena cava to bring the blood back the to baby's heart
Septum
Divides the left and right side of the heart
What happens at the walls of the capillaries
Gases and small moleculee like glucose
Systemic circuit
Includes all blood vessels except those in the pulmonary circuit
Lymph capillaries drain...
Into lymph veins which have valves for one way flow
Portal system
Is a vascular system that begins and ends in the capillaries
Lymphatic system
Is another vascular system in your body
What happens if the oval opening doesn't close after birth and how can it be corrected?
It can cause mixing of blood and blue babies -Cured by open heart surgery
What is special about the Lymphatic system?
It is separate from the cardiovascular system because it has its own veins and capillaries
Venules
Join together to form veins
Atrioventricular valves
Located between the atria and ventricles
Lymph contain what
Lymphocytes
Placenta
Membrane shared by the mother and baby across which gases, nutrients and wastes are exchanged
What are Arterioles mostly made of?
Mostly smooth muscle to allow for more control of the ateriole
Lymph
Once fluid enters the lymph vessel
Lymphatic system is a what system and explain
One way system that starts in the tissues and empties into the cardiovascular system
Description of Oval opening
Opening right between the right and left atria, covered by a flap that looks like a valve
Foramen ovale known as
Oval opening
Pulmonary circuit
Path of blood from the heart to the lungs
What contains the heart?
Pericardial sac
Jugular vein
Takes blood from the head to the anterior vena cava
Carotid artery
Takes blood to head, subclavian arteries/to arms branch off
Subclavian artery
Takes blood to the arms from the aorta
Mesenteric artery
Takes blood to the intestines
Renal arteries
Takes blood to the kidneys from the aorta
Iliac arteries
Takes blood to the legs from the aorta
Pulmonary artery
Takes unoxygenated blood from the right ventricle to the lungs
Arterioles
The branches of arteries
Where does blood first enter?
The vena cava
Arteries and artioles function
They carry blood away from the heart to tissues
What is special about Veins?
They have valves
Left side of the Ventricles is....
Thicker because the body is further from the heart
Right side of the Ventricles is....
Thinner because lungs are close to the heart
How are the umbilical arteries grafted?
To the iliac arteries
Left side pumps...
To the rest of the body
Lymphocytes
Type of white blood cell
