Topic 8- Exchange and transport in animals

Question 1

Why do multicelular organisms need transport systems?

Answer 1

-Cells in internal structures cannot access outside sources
-Therefore organisms need e.g blood vessels
-To supply all cells with oxygen, water, nutrients

substances are vital for life + prevent waste build up

Question 2

What is SA:V ratio?

Answer 2

-Surface area to volume ratio
-Giraffes have a larger SA:V than polar bear

Question 3

What does build up of Carbon Dioxide do?

Answer 3

-Dissolve in blood
-Acidic
-Acidosis

Question 4

What are specialised exchange surfaces?

Answer 4

-Efficient way of transporting substances

Question 5

Examples of exchange surfaces?

Answer 5

-Kidney (nephron walls)
-Leaf stomata
-Lungs
-Small intestine
-Gills
-Root hair cells

Question 6

What makes an exchange surface efficient?

Answer 6

-Short diffusion distance
-Large SA (more space)
-Higher temp (more collisions)

Question 7

How are alveoli’s adapt for gas exchange?

Answer 7

1) Millions of alveoli (clusters)
2) All covered in tiny capillaries
3) One cell thick-short diffusion distance
4) Spherical + tiny
5) Steep concentration gradient (constant co2 supply from capillaries)

Question 8

Fick’s law?

Answer 8

Rate of diffusion α (SA x Conc diff)/ Thickness

proportional to

Question 9

Why do single celled organisms not need transport systems?

Answer 9

-Small metabolic needs
-met by diffusion of substances in the air

Question 10

How are red blood cells suited to their function?

eurythrocytes

Answer 10

-Biconcave (SA)
-Haemaglobin (oxygen binds–> oxyhaemaglobin)
-Flexible (squeeeze through capilaries)
-No nucleus = more space

Question 11

Two types of white blood cells?

Answer 11

-Phagocytes
-Lymphocytes

Question 12

What do phagocytes do?

Answer 12

-Engulf pathogens + mix them with digestive enzymes
-In a ‘sac’

Question 13

How are phagocytes suited to thier function?

Answer 13

-Lobe nucleus (flexible–> engluf)
-Flexible membrane
-Contain digestive enzymes
-Attracted to pathogens through chemcial signals
-Non specific (can engulf many diff pathogens)

Question 14

What do lymphcytes do?

Answer 14

-Produce specific complementory antibodies
-Produce antitoxins to neutralise toxins
-Turn into memory lymphocytes

Question 15

How are lymphocytes suited to thier function?

Answer 15

-Large nucleus (produce antibodies)
-Fast antibody production
-Rapid cell division
-Produce antibodies and antitoxins

Question 16

How is plasma related to its function?

Answer 16

-Yellow Liquid carries blood components
-Hormones
-Platelets
-Protiens
-Carbon dioxide

primarily water

Question 17

How are platelets suited to thier function?

Answer 17

-Cell fragments
-Surface coated with protiens (for sticking)
-Clump together to form clots (stop bleeding)
-Dries + hardens = scab

Question 18

What happens to fibrinogen?

Answer 18

-Soluable
-Turns into insoluable fibrin when damaged

Question 19

What is the structure and function of an artery?

Answer 19

-Carries blood from the heart
-Small lumen= high pressure (from heart)
-Thick muscle layer = strength
-Thick elastic fibre layer = stretch
-Found deeper in body to prevent being damaged

Question 20

what is the structure of function of the vien?

Answer 20

-Larger lumen (hold more blood)
-Valves prevent backflow
-Thinner elastic and muscle layers

Question 21

what is the structure of function of the capillaries?

Answer 21

-One cell thick (short diffusioin distance)
-Blood flow very close to cells
-Permeable walls (easy for oxygen to diffuse across)

Question 22

The heart’s structure?

Answer 22

-Right and left Atrium
-Right and left ventricle
-Tricuspid and bicuspid valve
-Pulmonic and aortic valve

Question 23

What are the viens that connect to the heart?

Answer 23

-Superioir and inferioir Vena Cava
-Pulmanory vein

Question 24

What are the arteries that connect to the heart?

Answer 24

-Pulmanory artery
-Aorta (to body)

Question 25

What does the heart do?

Answer 25

-Pumos blood around the body in a **double circilatory system** -**Deoxygenated** blood in the right atrium and ventrical -*Pulmanory* *artery* to lungs for **gaseous** exchange -**Oxygenated** blood through *pulmanory* *vien* to heart to be pumped to rest of body (left side is thicker) through **aorta**

Question 26

How is the heart suited to its function?

Answer 26

-Thick muscle walls (strong pumps) -4 chambers seperated deoxy/oxyginated blood -Valves prevent backflow -Coronary arteries cover the heart to supply itself oxygen

Question 27

The process of a heartbeat?

Answer 27

1) Atrium systole (they squeeze blood into ventricles) 2) Ventricle systole (tricuspid and biscupid valves close, aortic and pulmonary valves open and ventricles squeeze blood into aorta and pulmonary artery) 3) Diastole (heart relaxed, allows to be filled with blood)

Question 28

What cells control heartbeat?

Answer 28

-Pacemakers in right atrium -Stimulate through small electrical impulses | can use an artificial pacemaker if irregular heartbeat

Question 29

What is respiration?

Answer 29

-Exothermic reaction -All living cells undergo to survive -Release energy from glucose (ATP) -For metabolic purposes

Question 30

What are the two types of respiration?

Answer 30

Aerobic= Oxygen + glucose --> CO2 and water Anerobic= Glucose ----> lactic acid -Anerobic produces less energy -Build up of lactic acid= oxygen debt + soreness

Question 31

What is anerobc respiration in yeast?

Answer 31

Glucose--> Ethanol + CO2

Question 32

**Core Practical:** Investigate the rate of respiration in living organisms

Answer 32

1) Add soda lime to test tubee (take out CO2) 2) Place cotton wool and organisms (small) 3) Add pung and capillary tube 4) Add to water bath at 30 degrees 5) Add coloured liquid to beaker and place cpaillary tube in 6) Measure starting place of liquid 7) Wait 5 mins and see new liquid placement 8) Repeat at diff temps | same no. of organisms

Question 33

How to measure cardiac output?

Answer 33

stroke volume x heart rate