Speciation is not a mechanism of microevolution.
Answer:
A) Hummingbirds drinking nectar from a plant.
Step-by-step explanation:
Here are some examples of natural selection: In a habitat there are red bugs and green bugs. The birds prefer the taste of the red bugs, so soon there are many green bugs and few red bugs. The green bugs reproduce and make more green bugs and eventually there are no more red bugs.
c.Chromatin in the nucleus condenses.
Prophase is the 1st stage. So in Prophase chromatin don't condence. It occurs at anaphase.
Answer:
The correct option is <u>C. The nervous system when the brain regulates the body's breathing and heart rate.</u>
Explanation:
The main function of the respiratory system is to exchange oxygen for carbon dioxide in the body.
The brain controls the rate at which the heart pumps blood. The pumping of the heart supplies oxygenated blood to other parts of the body. Hence, the rate at which heart pumps blood is very important to maintain homeostasis of the respiratory system.
The brain regulates the rate at which a person breathes. This rate is very important to breathe in the right amount of oxygen and to breathe out the right amount of carbon dioxide.
Mutations are the source of all new alleles. An allele is a variant form of a gene. Variations in alleles lead to variations in organisms. Positive mutations give an organism a better chance of survival. It means that the mutation may be passed on to the offspring. Negative mutations may lead to an early death.<span> Therefore, changes in alleles from one generation to another form the basis of evolution.</span>