Do you think that a part or slice of a substance will have a different density than the whole piece? Explain your ideas about this.

1: the largest region of the brain is the:

  cerebrum

2. the term "psychology" literally means:

the process or procedure of the science or study of the mind.

3. the area of the brain responsible for respiration, heart rate, and smooth muscle control of our blood vessels is t

medulla oblongata

4. the structure that conducts nerve impulses to and from the brain and serves as a reflex center for some sensory information without input from the brain is the:

spinal cord

5. the three-layered membrane that covers the brain and spinal cord and literally means membrane is called the:

meninges

6. the cord-like (string-like) structures that carry bio-electrical impulses from one part of the body to another are called

nerves

7. a group of nerve cell bodies that are found outside of the spinal cord and brain are referred to as:

ganglions or ganglia (pl.) “literal meaning knot”

8. the term that means spinal cord inflammation is:

myel/itis

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation: