Chromosomes are thread-like structures present in the nucleus, which carries genetic information from one generation to another. They play a vital role in cell division, heredity, variation, mutation, repair and regeneration.
When Timmy steps on the rose bush, the sensory receptor on his toe receives the stimuli, sends it the spinal cord through a sensory neuron which they initiates a response sent through a motor neuron to the muscle and he withdraws his leg in pain.
<h3>What is a reflex arc?</h3>
A reflex arc refers to the neuronal pathway which controls a reflex action.
A reflex action is an action which occurs involuntarily.
Examples of reflex actions include thhe following:
- withdrawing the foot quickly when one steps on a sharp object
- withdrawing the hand quickly when one touches a hot surface
- the je_rking of the knee
- coughing or sneezing, when irritants enter the nostrils.
Reflex actions do not need to involve the brain, hence they occur very quickly.
The path of a reflex arc begins with a sensory receptor which receives the stimuli, travels to the spinal cord through a sensory neuron which they initiates a response that is sent through a motor neuron to an effector such effector such as a skeletal muscle.
In conclusion, a reflex arc is the path of a reflex action through the body.
Learn more about reflex arc at: brainly.com/question/10003986
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Answer:
because the beaks are different and since they prefer other avaliable seeds.
because the population changes over time its called natural selection, in darwins drawings there were extremely different from eachother.
because when he drew normal finches and went to galapagos islands he saw that there were also finches but they looked completely different and he analyzed their beaks. there are animals who change over natural selection
Explanation:
Segments of DNA transferred from parent to offspring are called genes.
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