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Flashcards in Transport In Animals Deck (23):
1

Need for a transport system

Size
SA:volume
Level of metabolic activity

3

Good transport system properties

Fluid carry nutrients/oxygen/waste (blood)

Pump to create pressure of the fluid (heart)

Exchange surface to transfer substances through blood (capillaries)

Tubes/vessels to carry blood

2 circuits, pick up O₂ and deliver to tissues

4

In single circulatory systems…

Blood flow rate is slow and there's low pressure

5

Circuit where blood flows to lungs

Pulmonary circulation

6

Circuit where oxygen is transported around body and tissues

Systemic circulation

7

Open circulatory system

Blood not in vessels
Fluid bathes tissues/cells
Movement of body/muscular pumping circulates

8

What's bad about open circulatory systems?

Low blood pressure so slow flow

Circulation affects by body movements or lack of

9

What's good about closed circulatory systems?

High pressure so quick flow and rapid delivery/rapid removal
Transport is separate from body movements

10

Vessels' inner layer, single layer of cells

Endothelium

11

Arteries take blood ____ ____ ___ _____ with ____ ________

Away from the heart
High pressure

12

Artery structure to deal with high pressure

Standard structure of artery

Thick wall to withstand it
Small lumen to keep it

Inner layer is elastic tissue/fibre to stretch wall and maintain pressure
Middle layer is smooth muscle
Outer layer is collagen fibres for strength for pressure

13

Veins carry blood ____ __ ___ ____ at ___ ________

Back to the heart
Low pressure

14

Vein structure

Thin walls
Large lumen
No need to stretch/ recoil because has valves

15

Venules carry blood from…

Capillaries to veins
Walls consist of thin muscle/elastic tissue outside endothelium and thin outer collagen

16

Arterioles are…

Small vessels that carry blood from the artery to capillaries

Smooth muscle constricts arterioles to direct blood to parts

17

WBC

Leucocytes + platelets

18

Capillary structure

Thin walls
Narrow lumen
Walls are a single layer of endothelial cells
Leaky walls to allow blood plasma and dissolved substances through

19

Tissue fluid is…

Plasma leaking from capillaries and surrounding tissues
Supplies tissues with oxygen and nutrients
Happens by mass flow not diffusion

20

When exchange at capillaries occurs, diffusion happens between

Tissue fluid and cells
Nutrients and O₂ goes into cells and waste comes out of cells

21

Hydrostatic pressure is…

It pushes…

What the fluid exerts when pushing sides of vessel

Blood fluid out of capillaries at the arteriole end, only dissolved O₂ and nutrients pass because RBC and WBC are too big

22

At the venous part of the capillary the…

So…

Pressure is low

Allows tissue fluid back with the waste CO₂

23

Some tissue fluid goes to the……… which……

Lymphatic system

returns excess fluid back to the blood system

24

Why does size affect the need for a transport system?

A bigger size means cells are further from the surface so increased diffusion path