Transport Systems In Animals Flashcards
Function and structure of arteries
Blood vessels that carry blood away from the heart
Thick muscle layer and narrow central channel allowing them to carry blood at a high pressure without bursting
Function and structure of veins
Carry blood away from the organs and back to the heart
Thin muscle layer and wide central channel as blood is at a low pressure
Have valves that prevent blood flowing backwards
What is transported around mammals bodies in the blood?
Nutrients
Oxygen
Carbon dioxide
Function and structure of capillaries
Form networks of blood vessels that allow the exchange of substances between cells in tissues and organs and blood
Large surface area for exchange of substances
Capillary walls are only 1 cell thick to allow rapid diffusion of substances between blood and cells
What happens to oxygen in the blood when it reaches the organs?
Oxygen is released from oxyhemoglobin and diffuses out of blood into cells of the organs
What are the main structures in the lungs?
Trachea surrounded by rings of cartilage to keep airways open Lung: Bronchi Bronchioles Alveoli
What makes the alveoli good for gas exchange?
Large surface area
Good blood supply
Thin walls for rapid diffusion of gasses
What is mucus?
Sticky substances which traps dirt/germs preventing them from reaching the lungs where they could cause damage
What are cilia?
Small hair like structures that beat to move mucus up the windpipe away from the lungs to the throat where it is swallowed and the stomach acid makes it the dirt and germs harmless
What is peristalsis?
Food is moved through the digestive system using the muscles in the walls of the organs of the digestive system
Muscles behind food contact pounding it forward as muscles in front relax allowing the food to easily move forward
What happens to large insoluble molecules of food in the digestive system?
They are broken down by enzymes into small soluble molecules which can be absorbed across the lining of the digestive system and then move into the blood
The products of digestion
Starch - glucose/maltose
Fats - fatty acids and glycerol
Proteins - amino acids
What is the small intestine lined with?
Microscopic structures called villi that increase the rate at which the products of digestion can be absorbed into the blood.
What are the features of villi?
Thin walls - increase the rate of diffusion
A large surface area for absorption
Many capillaries - provide a good blood supply to aid absorption of glucose and amino acids
Lacteals- transport the products of sat digestion away from the digestive system
Function and structure of capillaries
Form networks of blood vessels that allow the exchange of substances between cells in tissues and organs and blood
Large surface area for exchange of substances
Capillary walls are only 1 cell thick to allow rapid diffusion of substances between blood and cells
