B4 Transportation Flashcards
What is blood plasma? What does it do?
Blood plasma carries red blood cells, white blood cells and platelets and it also carries many dissolved substances around your body, it is a yellowy substance/liquid
What does the Red Blood Cells do? What do they look like? Describe the structure.
Red blood cells pick up oxygen from the air in your lungs and carry it to the cells where it is needed. Having a dent in the middle increases surface area to volume ratio for diffusion. They have red pigment called haemoglobin. Red blood cells have no nucleus making more space for haemoglobin
What do the white blood cells do? Describe their structure. What do they look like?
White blood cells are bigger than red blood cells but there are fewer of them. They have a nucleus and form part of the body’s defence system against harmful microorganisms. Some form anti-toxins against poisons made by microorganisms, others engulf and digest invading bacteria and viruses.
What are platelets? What do they do?
Platelets are small fragments of cells. They have no nucleus. They are very important in helping the blood to clot the site of a wound (scab). Blood clotting is a series of enzymes-controlled reactions that result in converting fibrinogen into fibrin. This produces a network of protein fibres that capture lots of red blood cells
Double circulatory system
Humans have two loops in our body in which blood circulates. One is oxygenated, meaning oxygen rich, and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.
Artery characteristics
Thick walls.
Small lumen.
Thick layer of muscle and elastic fibre.
Vein characteristics
Relatively thin walls.
Large lumen.
Often have valves.
Capillary characteristics
Walls a single cell thick.
Tiny vessel with narrow lumen
How is the structure of an alveolus adapted for it’s function?
Alveolus provide a very large surface area. This is important for achieving the most efficiency of oxygen and carbon dioxide. The alveoli has a big supply if blood capillaries. This maintains the concentration gradient in both directions. Blood going into to the lungs is always relatively low in oxygen and high in carbon dioxide compared to the inhaled air.
Explain why the left ventricle wall is thicker than the right ventricle wall.
The left ventricle wall is thicker as it is larger and carries oxygenated blood. This means it needs a thick wall to protect it.
Name the different parts of an alveoli
- Bronchiole
- Blood away from alveolus
- Blood to alveolus
- Capillary
- Alveolus (air sac)
Ventilation (alveoli)
Ventilation moves air in and out and helps maintain a steep diffusion gradient.
Xylem cells
The xylem tissue carries water and mineral ions from the soil around the plant to the stem and the leaves.
Phloem tissues
The phloem tissue transports the sugars made by photosynthesis from the leaves to the rest of the plant. This includes transport to the growing areas of the stems and roots.
Translocation
Translocation is the movement of dissolved sugars from the leaves to the rest of the plant.
