Circulatory System Quiz Flashcards
Do all organisms require a circulatory system?
No, single celled organisms, sponges and yeast are examples as they don’t need to transport oxygen or nutrients (they can just absorb them as they are directly exposed to environment)
What are the functions of a circulatory system? (6)
- Delivers O2 from respiratory system
- Delivers nutrients from digestive system
- Delivers hormones from endocrine system
- Delivers chemicals or cells from immune system
- Delivers metabolic wastes from cells to kidneys and liver
- In warm-blooded animals, it plays a role in distributing thermal energy throughout body to maintain body temp
What are the 3 main features of circulatory systems?
- A fluid that circulates materials through the body
- A network of tubes in which the fluid circulates
- A pump that pushes the fluid through the tubes
What are open circulatory systems? (5)
Found in most invertebrates (snails, insects, crustaceans)
Circulatory fluid (hemolymph - mixture of blood and tissue fluid) pumped into interconnected system of body cavities (sinuses) where it bathes the cells directly
Contractions of one or more hearts forces hemolymph out circulatory tubes through sinuses
When the heart relaxes, hemolymph is drawn back to heart through open ended pores (pump and bucket)
Body movement can help circulation
What is a closed circulatory system? (3)
All vertebrates and some invertebrates have them (earthworms, squid, octopus)
Fluid (often blood) is contained w/in a network of tubes or blood vessels which separates the blood and the tissue
Tissue fluid surrounds the cells and provides a medium for diffusion of substances from the bloodstream to the cells (open-blood and tissue mix in tissues)
What is a two-circuit circular system?
Mammals, birds and crocodilians have it
Circulation to the lungs is separate from circulation to the body
2 parts - pulmonary circuit: delivers blood to lungs; systemic circuit: delivers blood around the body
How many liters of blood die the human body contain?
4-5L
What is the circulatory system made of?
Cellular component and intercellular component (plasma)
What is plasma?
Protein-rich liquid in which blood and platelets are suspended
Made mostly of water but also contains albumins, globulins and fibrinogen
What are albumins?
Determine how much water enters or leaves bloodstream
What are globulins?
Transport lipids, cholesterol, some fat-soluble vitamins and some minerals (immunoglobulins/antibodies- fight infectious diseases)
What are fibrinogens?
Plays a critical role in blood clotting
What does the cellular component consist of?
Red blood cells, white blood cells and platelets
What are red blood cells? What is the main function? How do they form? Is there a nucleus? How many days does it spend in circulation?
Aka erythrocytes
Shaped in Biconcave disks
Main function: carry O2 from lungs to body and carry CO2 from body to lungs
Formed from stem cells in marrow of vertebrae, ribs, breastbone, skull and bones of arms and legs
Has a nucleus when developing but it dissolves after
Spend about 120 days in circulation
What are white blood cells? Where are they formed? What are the 2 categories?
Aka leukocytes
Formed in bone marrow as well
2 categories are granular and agranular
What are granular leukocytes? What are the three kinds?
Have granules in their cytoplasm
Neutrophils: play role in immune system; first to travel to infection site; ingest microorganisms
Eosinophils: play role in immune system; releases enzymes during infection, allergic reaction and asthma
Basophils: play role in immune system; releases enzymes during allergic reaction and asthma
What are agranular leukocytes?
Specialized for engulfing bacteria and other microorganisms
Use phagocytosis to destroy bacteria/harmful substances (engulfs it and then releases enzymes to break it and the WBC down - pieces left behind as pus)
Two kinds- lymphocytes and monocytes
What are lymphocytes?
Produce antibodies that attack microorganisms or their toxins
What are monocytes?
Enlarge to become macrophages
Clean up bacteria, dead cells and other debris in bloodstream and tissue
What are platelets?
Small cell fragments produced from stem cells in the bone marrow
Essential in blood clotting, or coagulation
What are the three types of blood vessels?
Arteries, veins and capillaries
What are arteries?
Blood vessels that carry blood away from the heart toward body tissues
What is the aorta?
The single large artery that leaves the heart
It branches into other major arteries that carry blood through the body