Mass Transport In Mammals

Question 1

Mass transport in animals

Answer 1

Mass flow, the bulk movement of substances through transport systems
Transport systems linked with specialist exchange system, maintain con grad

Question 2

Transport systems in mammals

Answer 2

Larger organisms cannot exchange materials sufficiently across surface
Need exchange surfaces, eg alveoli in lungs
Required to take material between cells, exchange surface

Question 3

What do transport systems in mammals rely on?

Answer 3

SA:V

How active the organism is

Question 4

Features of a transport system

Answer 4

Medium to carry medium across
Medium needs to be moved in bulk over large distance
Closed system of tubular vessel containing medium
Mechanism for moving transport medium, eg, muscular contractions of heart

Question 5

Circulatory system in mammals

Answer 5

Double circulatory system
Important to maintain high body temp and high rate of metabolism
Material exchange takes place by diffusion, over large SA, short distances, steep diffusion gradient

Question 6

Vessels in systemic circulation

Answer 6

Hepatic artery and vein
Hepatic portal vein (from stomach)
Renal artery and vein

Question 7

Vessels in pulmonary circulation

Answer 7

Superior vena cava
Pulmonary artery
Pulmonary vein
Aorta

Question 8

Blood vessels

Answer 8

Arteries
Arteriolar
Capillaries
Venues
Veins

Question 9

Structure of blood vessels

Answer 9

Tough outer layer
Muscle layer
Elastic layer
Endothelium (caps only have E and L)
Lumen

Question 10

Function of veins, ventures

Answer 10

Blood to heart from body
Thin collagen walls
Low pressure
Large lumen, reduce flow resistance
Valves to prevent backflow
Low pressure blood
Deoxygenated blood except pulmonary vein

Question 11

Function of capillaries

Answer 11

Allow diffusion of materials between blood and tissues
Very thin permeable walls, 1 cell thick, material exchange
V small lumen, short diffusion pathway for material exchange
No valves
BP falls in capillaries
Changes from oxygenated to deoxygenated

Question 12

Function of arteries, arterioles

Answer 12

Carry blood from heart to body
Thick walls, smooth elastic layers, restrict high pressure
Muscle layer aids pumping
Small lumen
No valves except in pul artery, aorta
High BP
Oxygenated except in pul art

Question 13

Arterial movement

Answer 13

Expand during systole
Recoil during diastole
Arterioles, more muscular, vasoconstriction, close off cap beds
Vasodilation, opens up cap beds
Changes occur under control of medulla

Question 14

Venous movement

Answer 14

Leg contractions help blood move up against gravity

DVT caused by lack of movement

Question 15

Tissue/ Interstitial fluid

Answer 15

Contains glucose, amino acids, fatty acids, salts, oxygen. No AA
Similar to plasma
Supplies substances to tissues
Recieves waste, CO2
Tissue fluid moves into and around cells, diffusion

Question 16

Hydrostatic pressure

Answer 16

Hydrostatic pressure of tissue fluid out caps, prevents outward fluid movement

Question 17

Water potential in cap beds

Answer 17

Lower WP of blood due to plasma proteins

Pulls water back into blood within capillaries

Question 18

Blood composition

Answer 18

55% plasma
1% WBC
44% RBC
Hematocrit can change

Question 19

Tissue fluid formation

Answer 19

High hydrostatic pressure in arterioles end of cap, blood plasma squeezed out cap
Cell proteins too big
Tissue fluid formed, material exchanged from fluid to cel by 4 methods of transport
Low hydrostatic pressure at venous end, lost too much plasma, plasma back into caps
Water enters caps by osmosis
NOt all plasma returns, drains into lymph vessels in cap beds
Waste diffuses into caps
Lymph, similar to tissue fluid, move digestive product fats
Narrowing of vessels pushes fluid out of vessels, ultrafiltration

Question 20

Lymphatic system

Answer 20

Made up of system of lymph vessels along veins
Lead to heart, lymph drains back into blood system at superior vena cava
Helped by muscle contractions like in veins
Vessels also absorb fats from small intestines from lacteals
Networks in various places, lymph nodes
Swollen if more WBC needed to fight infection