Skeletal and Muscular
What is the main job of the skeletal system?
to support and protect the body and help it move
What is the main function of the digestive system?
To break down food so nutrients can be absorbed and used by the body.
What gas does the respiratory system bring into the body?
Oxygen
What organ pumps blood throughout the body?
the heart
What organ is the control center of the nervous system?
The brain.
Put these levels in order from simplest to most complex: organ, organism, cell, tissue, organ system.
Cell → tissue → organ → organ system → organism.
Name 2 major jobs of the muscular system
It helps the body move and helps move substances within the body.
Where does digestion begin?
The mouth.
What gas does the respiratory system remove from the body?
Carbon dioxide.
What is one important substance the blood carries to body cells?
Oxygen or nutrients
What is the main job of the nervous system?
To receive information, process it, and send signals that control and coordinate the body.
A group of similar cells working together forms what?
A tissue.
How do muscles and bones work together to create movement?
Muscles contract and pull on bones at joints, causing body parts to move.
What organ absorbs most nutrients from digested food?
The small intestine.
What major organs of the respiratory system exchange gases with the blood?
The lungs.
What is the main job of the circulatory system?
To transport blood, oxygen, nutrients, and wastes throughout the body.
You accidentally touch something hot and quickly pull your hand away. What system detects the danger and sends messages that help your body respond?
The nervous system.
The heart contains several types of tissues working together. Therefore, the heart is classified as what level of organization?
An organ.
A student bends an elbow to lift a book. Which two body systems are working most directly together?
The muscular and skeletal systems. Muscles contract and pull on bones at the elbow joint to move the arm.
Put these in the correct order: stomach, mouth, large intestine, esophagus, small intestine.
Mouth → esophagus → stomach → small intestine → large intestine.
Why does your breathing rate usually increase when you exercise?
Working cells need more oxygen and produce more carbon dioxide, so breathing increases to exchange gases faster.
Why are the respiratory and circulatory systems closely connected?
The respiratory system exchanges oxygen and carbon dioxide, while the circulatory system transports those gases between the lungs and body cells.
How does the nervous system work with the muscular system when you decide to kick a ball?
The nervous system sends signals to the muscles, telling them when and how to contract to move the leg.
Why is a human considered an organism rather than an organ system?
A human is a complete living thing made of multiple organ systems working together.
Why would damage to a muscle attached to a healthy bone make movement difficult even if the bone is not injured?
Bones cannot move by themselves. Muscles must contract and pull on bones to produce movement.
How does the digestive system help your muscles even though food does not travel directly into your muscles?
The digestive system breaks food into nutrients, which are absorbed into the blood. The circulatory system carries those nutrients to muscle cells.
Oxygen enters the lungs when you breathe. Explain what must happen next for oxygen to reach a muscle in your leg.
Oxygen moves from the lungs into the blood, and the circulatory system carries the oxygen-rich blood to the leg muscles.
A person’s heart beats faster during exercise. Explain why this helps the body maintain its needs.
A faster heartbeat moves blood more quickly, delivering more oxygen and nutrients to active cells and carrying away wastes such as carbon dioxide.
A student sees a ball flying toward them and catches it. Describe the role of the nervous system in this action.
The eyes detect the ball, the nervous system sends information to the brain, the brain processes it, and signals are sent to muscles to move the arms and hands.
A runner needs oxygen and nutrients delivered to muscle cells while carbon dioxide is removed. Name at least three systems involved and explain their roles.
The respiratory system brings in oxygen and removes carbon dioxide; the circulatory system transports oxygen, nutrients, and wastes; the muscular system uses oxygen and nutrients to produce movement. The digestive system also supplies nutrients.