Page 9 - Science B.B Prim.4 concept 2&3 t.1 e-book _2024-2025. - Copy (1)_Neat
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Egyptian jerboa
A desert rodent searches for food at night.
It has large and senstitive ears to detect even a quiet snake.
It has long hind legs to jump a long distance.
It’s feet and toes have hair to grip the sand when it hops or jumps.
It hops in zigzag to escape quickly from danger. “Behavioral adaptation”
How does an Egyptian jerboa feel the presence of snakes?
1- The sensory receptors in the jerboa’s ears send the information
along the nerves to its brain.
2- The jerboa’s brain translates this information and alerts its legs to
move by sending a message through the nerves to the legs.
? It can feel the presence of snakes.
3- The jerboa’s strong hopping legs start to jump away from the snake
in zigzag pattern.
4- This happens in less than one second, the time taken by
jerboa to react to danger is known as:
"Reaction time".
Reaction time: It is the time taken by the body of a living organism
to respond and react to different information from the environment.
First Term Both human and jerboa move quickly
away from danger.
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