Students who demonstrate understanding can: Gather and synthesize information that sensory receptors respond to stimuli by sending messages to the brain for immediate behavior or storage as memories.
Assessment boundary: Assessment does not include mechanisms for the transmission of this information.
Official wording from the Next Generation Science Standards (NGSS Lead States, 2013). NGSS is a registered trademark of WestEd. Neither WestEd nor the lead states and partners that developed the NGSS were involved in the production of this page, and they do not endorse it. View on nextgenscience.org
Touch a hot pan and you pull your hand away before you even think about it. Smell cookies baking and a memory of a family kitchen might come flooding back. Both experiences start with sensory receptors: specialized cells in the eyes, ears, nose, tongue and skin that respond to stimuli such as light, sound, chemicals, pressure and temperature. The receptors send messages along nerves to the brain, which either triggers an immediate behavior or stores the information as a memory.
Students gather and synthesize information from several sources, such as texts, videos, reaction-time experiments and diagrams, to explain this pathway. They should be able to describe what a stimulus is, which receptors detect different stimuli, and how the brain uses the incoming messages in two different ways: responding right now, or saving the information so it can shape behavior later.
How the electrical and chemical signals actually travel along nerves is beyond this standard, so the focus stays on the overall route from receptor to brain to response or memory.
Eyes and ears detect the stimulus, but the experience of seeing or hearing happens when the brain interprets the messages it receives.
Some responses, like blinking when something flies at your eye, happen very quickly with little thinking. Others, like choosing what to eat, involve memory and decision-making.
Information from the senses is stored by the brain. Your nose detects a smell, but the memory it triggers is held in the brain.
In a reaction-time test, a student catches a dropped ruler after it falls 15 cm on her first try and 9 cm after ten practice tries. Explain the pathway involved and why her catch improved.
Answer: Eyes detect the fall, nerves carry messages to the brain, the brain signals the hand to grab; practice is stored as memory, which shortens the reaction from 15 cm to 9 cm of fall.
Ruler-drop reaction tests, two-point touch tests and taste or smell investigations give students firsthand evidence to combine with reading. Ask them to build a flow chart (stimulus, receptor, nerve, brain, response or memory) and then annotate it with evidence from each source they used.
Assessment expects synthesis, so have students cite where each piece of evidence came from. Keep explanations of how impulses travel out of scope for now.
Original questions written for this standard. Choose an option or type your answer, then press Check. Every question has a worked explanation.
Answer: C) A change in the environment that an organism detects
A stimulus is something, such as light, sound or heat, that a receptor can detect.
Answer: B) Eye
Light receptors are in the eyes.
Answer: brain (also accepted: the brain)
Sensory messages travel along nerves to the brain, which processes them.
Answer: D) Sensory information combined with memory guided behavior
Smell receptors sent a message to the brain, which used a stored memory to choose a response.
Answer: C) Nerves
Nerves carry signals between receptors, the brain and muscles.
Answer: skin (also accepted: the skin)
The skin has receptors for touch, pressure, heat and cold.
Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
Plan and conduct an investigation to provide evidence that feedback mechanisms maintain homeostasis.
A full lesson with slides, activities and an exit ticket on senses, signals and memory, pitched to grades 6-8 and editable in PowerPoint or Google Slides.
Make a lesson βA printable, differentiated worksheet on MS-LS1-8 with an answer key, ready in about a minute.
Make a worksheet βTurn senses, signals and memory into a quiz students answer online that marks itself, with a class summary for you.
Build a test βGathering and combining information from texts, videos and simple experiments, such as reaction-time tests, to explain how senses send messages to the brain.
No. The assessment boundary excludes the mechanisms that transmit the information.