Transport systems in multicellular animals

Question 1

Why do larger organisms need specialised transport systems?

Answer 1

• high metabolic demands
  
  • large O2 demand and produce lots of waste
• smaller sa:v
  
  • diffusion distances increase in size
  • too slow
• hormones or enzymes may be made in one place but needed in anotherhormones or enzymes may be made in one place but needed in another
• waste products need to be removed nutrients need to be transported to cells

Question 2

What are the common features of a circulatory system?

Answer 2

• carry gases, nutrients, waste products and hormones
• liquid medium that circulates around the system (blood)
• they have vessels that carry the medium
• a pumping mechanism to move the fluid around

Question 3

What is the difference between a closed circulatory system and a open circulatory system?

Answer 3

open: very few vessels to contain the blood, pumped straight into the body cavity
closed: blood is enclosed in blood vessels and it does not come directly into contact with the cells heart pumps the blood around by the heart and substances diffuse through the walls

Question 4

What are the features of a single circulatory system?

Answer 4

single: found in fish blood is pumped from the heart and travels all around the body before returning to the heart first set of capillaries exchange O2 and CO2, second set substances are exchanged between cells

Question 5

What are the features of a dobule circulatory system?

Answer 5

double: most mammals are active and maintain their body temperature, made possible by their double most efficient way blood travels twice from the heart higher pressure and fast flow is maintained