what is a cell?
A cell is the basic unit of life; all living things are made of cells.
What organ pumps blood around the body?
The heart.
What muscle helps you breathe in and out?
The diaphragm.
What is the main job of the digestive system?
To break down food and absorb nutrients.
What is energy?
Energy is the ability to do work or cause change.
What part of the cell controls what enters and leaves?
The cell membrane controls movement of substances in and out of the cell.
Which blood vessels carry blood AWAY from the heart?
Arteries.
What is the main job of the respiratory system?
To bring oxygen into the body and remove carbon dioxide.
. What organ uses acid and enzymes to break down food?
The stomach.
What type of energy does a moving object have?
Kinetic energy.
What is the function of the mitochondria?
Mitochondria release energy for the cell during respiration.
What prevents blood from flowing backward in the heart?
Valves.
What are the tiny air sacs where gas exchange happens?
The alveoli.
What is the role of bile in digestion?
Bile breaks down fats into smaller droplets so they’re easier to digest.
What is the rule about energy that says it cannot be created or destroyed?
The law of conservation of energy.
What does the nucleus do?
The nucleus controls the cell and contains the DNA (instructions).
What do red blood cells carry?
Oxygen.
Why are alveoli only one cell thick?
So gases (oxygen and carbon dioxide) can move in and out quickly.
Where does most nutrient absorption happen?
The small intestine.
What type of energy is stored in food, batteries, and fuel?
Chemical energy.
What is the difference between plant and animal cells?
Plant cells have a cell wall, large vacuole, and chloroplasts; animal cells do not.
whast the use of plasma, red blood cells and white blood cells
red- carries oxygen
white- immune system
plasma- carries nutrients and waste, hormones
How do the respiratory and circulatory systems work together?
The respiratory system adds oxygen to the blood, and the circulatory system transports it around the body.
What are villi?
Tiny finger-like structures in the small intestine that absorb nutrients.
If something is lifted higher off the ground, what type of energy increases?
Gravitational potential energy.