Capillaries and lymph Flashcards
2 main body compartments
60% water and 40% solid
Subparts of the water make up in body
2/3 intracellular fluid
1/3 extracellular fluid
Parts of extracellular fluid
Interstitial fluid
Plasma
Interstitial fluid
Fluid between the cells (surrounding and within tissue)
Types of capillaries
Continuous
Fenestrated
Sinusoidal
Continuous capillary
Tightly joined epithelial cells that regulate selective molecular exchange
Leaky junctions at the cleft of the cells
Fenestrated capillaries
Contains pores that facilitate increased permeability for fluid and small molecules
Location of fenestrated capillaries
Intestinal wall and endocrine organs
Which capillaries have a continues basement membrane
Continuous and fenestrated
Sinusoidal capillary
Capillaries with large gaping spaces enabling passage of cells and large molecules
There is an increase in exchange across the membrane so decrease in regulation
2 primary pressures acting on water within capillaries (starling forces)
Hydrostatic pressure and oncotic pressure
Starling forces
Forces that drive the fluid exchange in capillaries
Determines net movement of H20
Hydrostatic pressure
Filters water out of the capillary into the interstitial space
Forces within hydrostatic pressure
Cap. hydro pressure pushes fluid out of capillary
Interstitial hydro pressure pushes fluid into the cap.
Oncotic pressure
Absorbs water from the interstitial space into capillary
What creates constant oncotic pressure in blood vessels
Albumin
How to determine if net efflux or influx of water
If the answer is negative then water moves into the capillary
If answer is positive water moves out
Lymphatic system functions
Return excess interstitial fluid to the venous circulation
Pick up fat absorbed and transfer to circulatory system
Filter for pathogens
Thoracic lymphatic duct location
Largest lymph vessel, located in posterior mediastinum and terminates in left brachiocephalic vein
Function of thoracic lymphatic duct
Collects lymph from all parts of the body except the right side of head, neck, thorax, and right upper limb
Right lymphatic duct
Terminates in the right brachiocephalic vein
Function of the right lymphatic duct
Collects lymph from right side of the head/neck, right thorax, and right upper limb
Lymph nodes
Where unfiltered lymph drains
Lymph node and immune response
Dendrite in node detects bacteria and presents antigen
B cells react and make antibodies
T cells and luymph
Circulate between lymph nodes, lymph, and blood
Looks out for pathogens that have been tagged
In fetus where does oxygen come from
Placenta via the umbilical cord
Umbilical vein
Supplies fetus with needed nutrition and 02
Umbilical arteries
Delivers waste products and CO2 from fetus to placenta
Ductus venosus
Vessel that directs blood from the umbilical vein directly to the IVC, so bypasses the liver
Travel of ductus venosus
Placenta
umbilical v
left portal v
ductus venosus
IVC
Ligamentum venosus
What used to be the ductus venosus
Foramen ovale
Opening between the RA and LA in a fetus
Purpose of foramen ovale
Shunts oxygenated blood from RA to LA (no lung circulation)
Hypoxic pulmonary vasoconstriction
Arteries in lungs constricted because of no 02 flow, increased resistance to BF, pulmonary arteries have increase in pressure resulting in increase pressure in the RA, higher than LA possible for foramen ovale valve
Closing of foramen ovale
Once LA has higher pressure during normal function the valve is pressed closed until it fuses with the heart tissue
Ductus arteriosus
Fetal blood vessel that shunts blood from pulmonary arteries to descending aorta allowing blood from RV to bypass non functioning lungs
Closing of ductus arteriosus
Once pulmonary function starts, O2 is introduced which constricts and terns into ligamentum arteriosum
