Animal Transport Flashcards
Why do multicellular organisms need a mass transport system
- constant supply of nutrients e.g glucose
- constant supply of oxygen around body
- water products produced e.g carbon dioxide needs to be continuously removed
Large more active animals e.g humans,fish and birds cannot rely on diffusion alone
- cells are very metabolically active + need rapid supply of oxygen and nutrients
- produce large amounts of waste products that need removal so rely on double pum
Arteries can resist any chain of bp flowing though what allows them to do this?
Thick layer of muscle in tunica media
-arteries to expand + relax
- amount of muscle in artery increases as further AWAY from heart
Thick elastic layer in tunica externa
- vessel to recoil (diastole) + reduces chance of bursting
- stretches when high bP (ventricular systole) = reduced pressure
- so recoil inward as pressure DROPS
- blood flow enerend out
Which components are found in ALL blood,tissue fluid and lymph
- fatty acids AND carbon dioxide
- tissue fluid + lymph formed from plasma and are small dissolved subst found in it = forced out of blood through “leaky” capillary walls —> bathing cells
What is meant by double circulatory system
- blood passes twice through heart during one complete circulation of the body
Loop 1 = pulmonary circulation to oxygenate blood in lungs + remove CO2
Loop 2= systemic circulation that delivers oxygenated blood to all cells/tissue + returns blood higher in CO2 to heart to pass through PCS
What tissues are found in ALL blood vessels?
- endothelial as lining of all BV
- made of squamous epithelium + smooth to reduce friction as blood flows through
Arteriole is small BV leading to capillary bed in tissues and one role is to increase/decrease blood flow to tissue.
Why can arterioles carry out this function?
- Muscular fibers so can contract = narrowing lumen
- Muscle fibers can relax = widening/dilating lumen
- controlling blood flow into capillary bed
LABELLING GRAPH OF BC’S
- Erethrocyte = bioconcave shape + no nucleus
- Lymphocyte= large round nucleus taking up nearly ALL cell vol
- Phagocyte= lobed nucleus
Venules
- formed when all capillaries from capillary bed + join together = large BV/Venules
- Venules JOIN —> Veins
3 layers arteries + veins composed of
- Inner ENDOTHELIAL LINING = made of squamous epithelium/flat layer of cells + smooth —> less friction between moving blood AND elastic fibers
- Middle layer TUNICA MEDIA = smooth muscle —> collagen + elastic fibers
- Outer layer TUNICA EXTERNA = contains elastic fibers + collagen fibers
How are capillaries adapted for their function as exchange vessels?
- One cell thick/thin capillary wall
- Endothelium/epithelium for wall
- Short diffusion distance
- Endothelial pores
- More gas exchange
- Large SA:V
7.Small lumen + slows down flow of rbc’s
BLOOD PLASMA + TISSUE FLUID
- pale yellow colored fluid + flows through capillaries in tissue = leaks through gaps between cells of capillary walls
- spaces filled w leaked plasma = TISSUE FLUID
- Tissue fluid IDENTICAL to blood plasma BUT LESS PROTEIN MOL —> protein mol too big to leak through capillary cell
Why is blood plasma good solvent?
- Water w subst dissolved in it e.g glucose,urea,plasma proteins etc
- Water main component of blood/tissue fluid
- Water able to transport POLAR mol e.g glucose from SI to liver/body cells
- Blood plasma transports heat around body = water high SHC —> absorb lots of thermal energy w/o altering blood temp too quickly
4.High SHC of water in tissue fluid = whole body maintains relatively constant temp
How much fluid leaves the capillary to form tissue fluid via Osmosis?
- occurs due to 2 opposing pressures
- Arterial end of capillary bed = BP in capillary HIGH enough —> push fluid out into tissue
- Tissue fluid DOES NOT have high protein conc that blood plasma has = LOW SOLUTE POTENTIAL
- So by OSMOSIS - water in tissue fluid osmotically moves into capillaries from tissue fluid as water mol move from H-L conc down WG
ROLE OF TISSUE FLUID
- forms immediate environment of each body cell
- exchange of materials between cell + blood via TF
- Homeostasis = maintaining constant internal environment of TF -> OPTIMUM ENVIORNMENT in TF so cells can work best
