The Heart
What is the heart?
Works as a pump to move blood around the body.
What are the four main components of blood?
RBC, WBC, Plateles and plasma
Name the three types of blood vessels.
Arteries, veins, capillaries.
How many chambers does the heart has?
Right atrium, left atrium, right ventricle, left ventricle.
What is the role of red blood cells?
Carry oxygen, nutrients, and wastes.
What is the function of arteries?
Carry blood away from the heart; thickest walls withstand high pressure created by the heart.
How does oxygenated blood enters the heart?
Right atrium takes in blood with carbon dioxide; squeezed down into right ventricle; taken to lungs where oxygen replaces carbon dioxide.
Describe how platelets help in the clotting process.
Gather at injury site; extend thin, thread-like extensions (filopodia); change into spider-like form; form a plug to stop bleeding.
Explain why capillaries have the thinnest walls among blood vessels.
Thinnest walls allow substances like oxygen and sugars to pass through into or out of the blood for exchange between blood and tissues.
How you can calculate your pulse rate by your own?
Oxygen-carrying blood from lungs enters left atrium; pumped into left ventricle; starts journey throughout the body.
In a centrifuge, why do red blood cells settle at the bottom while plasma is at the top?
Blood spun at high speed in centrifuge divides into components; red blood cells are heaviest so settle at bottom; plasma is lightest liquid at top.
Describe how veins ensure blood flows in one direction toward the heart.
Veins carry blood back to heart under low pressure; special valves help blood go only one way, preventing backward flow.
If the heart's chambers did not contract in sequence, how might this affect the exchange of carbon dioxide and oxygen in the body? Analyze based on the blood flow process.
Non-sequential contraction could mix deoxygenated blood (from body to right side) with oxygenated blood (from lungs to left side), preventing proper direction to lungs for CO2 release and O2 pickup, or to body for O2 delivery, leading to inefficient gas exchange.
How might the unique shape of red blood cells be compromised in sickle cell disease, and what impact could this have on their ability to move through blood vessels?
In sickle cell disease, red blood cells become hard, sticky, and C-shaped instead of flexible disc; this irregular shape makes them clog and block blood flow through narrow vessels.
If a vein lacked its special valves, how could this affect blood flow under low pressure compared to arteries? Analyze the structural differences.
Without valves, low-pressure blood in veins could flow backward; veins are less muscular and stretchy than arteries, which use high pressure and thick walls to push blood forward without needing valves.