Heart Flashcards
(16 cards)
How are muscles controlled?
Muscles are controlled by the nervous system, with signals from the brain traveling down the spinal cord and along nerves to muscles.
How are muscle cells adapted to their function?
Muscle cells contain strands that can shorten to produce a pulling force, which requires energy from respiration.
How are oxygen and nutrients delivered to muscles?
Oxygen and nutrients required for respiration are carried to the muscles in the blood. Nutrients are carried in the plasma, while oxygen is carried on red blood cells.
What is the role of white blood cells in the blood?
White blood cells attack micro-organisms.
What is the purpose of the breathing system?
The breathing system allows air to enter and leave the lungs, enabling oxygen to get into the blood and carbon dioxide to leave the blood.
What happens during gas exchange in the lungs?
Oxygen leaves the lungs and enters the blood, while carbon dioxide, a waste product from respiration, leaves the blood and enters the air in the lungs.
What is breathing?
Breathing is the movement of the muscles in your diaphragm and between the ribs, causing changes in the volume of the lungs.
What is ventilation?
Ventilation is the movement of air into and out of the lungs as breathing occurs.
How does blood circulate in the body?
Blood is carried to the heart by veins, enters the chambers of the heart, and is then forced back out when the heart muscle contracts.
What connects arteries and veins?
Arteries are connected to veins by capillaries, which are small vessels with very thin walls that allow oxygen and nutrients to leave the blood.
What are drugs?
Drugs are chemicals that affect how the body works, some of which can damage organs and may be addictive.
What are medicines?
Medicines, such as antibiotics, are drugs that help people suffering from diseases.
What are recreational drugs?
Recreational drugs are taken for their effects on the body, such as caffeine in coffee and alcohol, which are legal drugs.
What are illegal drugs?
Illegal drugs, such as heroin and ecstasy, are banned due to their harmful side effects.
What are depressants?
Drugs that slow down the nervous system are called depressants, such as alcohol, which alters behavior and slows reaction times.
What are stimulants?
Drugs that speed up the nervous system are called stimulants, with caffeine being a common example.
