Natural selection lead to different species when the squirrels were separated, some of them acquired traits better suited for their new environment. This allowed them to survive and reproduce better than others. Over time, each group evolved to display unique traits for their different environments until one species evolved into two.
Explanation:
The speciation in the squirrels due to the barrier in canyon occurred due to this. Such speciation is called allopatric speciation.
Speciation leads to formation of new species from the existing species due to change in their habitat or physical structure.
The squirrels on the two different side of canyon adapted to the habitat they are in. Their reproductive cycles, habitat and adaptation mode has become different due to the change in environment.
The species of squirrels became two as they reproduce and passed on the traits for survival in the environment which they had adapted.
The squirrels have become <em>reproductively isolated</em> also.
Genetic divergence takes place due to natural selection as squirrels arenow two different species.
The chronological order of the response brought about by the nervous system is as follows.
1. Sensory receptors in the arteries detect low oxygen levels.
2. Sensory neurons generate an impulse.
3. The central nervous system relays an impulse to certain brain regions.
4. The brain sends signals through motor neurons.
5. Isabel's breathing rate increases.
The response to a stimulus is called a reflex action and the pathway traveled by the reflex action is called the reflex arch. A reflex action is an automatic involuntary response to a stimulus which minimizes any damage to the body. During conditions of low levels of oxygen in the body, the receptors detect the stimulus of low oxygen levels which could pose a threat to the individual and sensory neurons generate an impulse. It reaches the central nervous system and then the brain. In turn, brain sends signals through the motor neurons that carry a message and help in increasing the breathing rate of Isabel.
Answer:
is the process of breeding only organisms with desirable traits
Explanation:
Answer:
The correct option is E) Contraction still occurs because Ca2+ can enter the cell directly through Ca2+ channels in the plasma membrane and bind to calmodulin.
Usually, the calcium ions are released from the sarcoplasmic reticulum of a cell during a muscle contraction, but if those are blocked, the contractions is an cell can still arise through the calcium ions which are present in the cell membrane of a cell.
Explanation:
Endoplasmic reticulum is one of the cell organelles found in the cytoplasm of the cell. It is an important cell structure. It is made up of folded membranes.
- In the endoplasmic reticulum protein is synthesized.
- It helps in the transport of protein molecules to the golgi apparatus.
- Protein is usually folded in the endoplasmic reticulum.
Learn more:
Endoplasmic reticulum brainly.com/question/2622106
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