7th grade · Science · Unit 2 of 8
Body Systems
Nerves, hormones, kidneys and more
What your child practices
How the nervous and endocrine (hormone) systems send messages, how the excretory system removes waste, and the basic organs of the reproductive system, all at a simple organ-and-job level.
Arizona Academic Standards learning standard: 7.L1U1.10 · how cells, tissues and organ systems keep animals alive
How we explain it
Children can open this short lesson before they practice.
- The nervous system sends fast signals along nerves. A reflex is fast and automatic.
- The endocrine system sends slower messages with hormones in the blood.
- The excretory system removes waste: kidneys filter blood and the bladder stores urine.
Example: You pull your hand away from a hot pan before you think. What is this? It happens automatically. It is very fast. Answer: a reflex
Body Systems in Arizona
In the Arizona Academic Standards, this is unit 2 of 8 in 7th grade Science, after Cells: Life's Building Blocks and before Our Senses.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Arizona Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Which body system lets you feel a cold breeze on your skin?
🌬️- the endocrine system
- the nervous system
- the excretory system
- the reproductive system
the nervous system
Hint: Sensors in your skin send messages along nerves to your brain.
Question 2
Which body system does each part belong to? Tap an item, then tap its basket.
Sort into: ⚡ nervous system · 🚰 excretory system · 🧪 endocrine (hormone) system
- 🏃adrenal glands
- 💧kidneys
- 🔗spinal cord
- 〰️nerves
- 🎛️pituitary gland
- 🎈bladder
⚡ nervous system: spinal cord, nerves · 🚰 excretory system: kidneys, bladder · 🧪 endocrine (hormone) system: adrenal glands, pituitary gland
Hint: The nervous system carries fast electrical messages. The excretory system removes wastes. Endocrine glands release hormones into the blood.
Question 3
What does the reproductive system make possible?
- digesting food
- keeping your balance
- producing offspring (babies)
- removing waste from the blood
producing offspring (babies)
Hint: To reproduce means to make new living things of the same kind.
Question 4
A ball is thrown to you. Put the steps in order as your nervous system helps you catch it.
- Motor nerves carry signals to your arm muscles
- 👀Your eyes see the ball coming
- 🙌Your hands close around the ball
- 🧠Your brain decides to catch it
- Sensory nerves send the message to your brain
Your eyes see the ball coming → Sensory nerves send the message to your brain → Your brain decides to catch it → Motor nerves carry signals to your arm muscles → Your hands close around the ball
Hint: Messages travel from your senses to your brain, the brain decides, and then messages travel out to your muscles.
Question 5
What are the main parts of the nervous system?
🧠- brain, spinal cord and nerves
- kidneys, bladder and ureters
- lungs, windpipe and diaphragm
- heart, blood and blood vessels
brain, spinal cord and nerves
Hint: The nervous system is your body's message network. The brain and spinal cord are the control center, and nerves reach every part of you.
Question 6
Using the table, which kind of message controls slow changes like growing taller over many years?
Two ways the body sends messages Feature Nerve signals Hormones Travel through nerves the blood Speed a fraction of a second seconds to hours Effect lasts a short time minutes to years - nerve signals
- hormones
- neither one
hormones
Hint: Look at the Effect lasts row. Which message's effects can last for years?