Question 1

Elements in the same period have the same __.

valence electron

electrons

atomic number

valence shell number

Question 2

Which element has the greatest reactivity? (Refer to a periodic table)

Phosphorous (P)

Chlorine (Cl)

Sodium (Na)

Lithium (Li)

Explain how the cell cycle is normally controlled, including reference to the role of tumor-suppressor genes:

Genetic drift refers to changes in the gene pool of a population that result from O A. injuries caused by male competition O B. changes in the number of polygenic traits O c. a type of artificial selection D. random changes in allele frequencies

What kind of information would be required if karyotype analysis were to be used to detect the genetic disorders of real organisms?

What causes exhalation?

Why is water so effective at hydrogen bonding? Choose 1 answer: (Choice A) Oxygen is very electronegative and strongly attracts hydrogen's electron.

What effect on the evolution of mammals was caused when the continents drifted apart?

What does the bacterial cell, human cell and plant cell have in common?

Which of the following correctly identifies the purpose of the ribosomes? A: Ribosomes are responsible for the cell division B: Ribosomes contain all the genetic material found in the cell C: Ribosomes are where most proteins are constructed in the

Which of the following statements is true? (a) Phospholipids will spontaneously form liposomes in nonpolar solvents. (b) In eukaryotes, all membrane-enclosed organelles are surrounded by one lipid bilayer.

Which type of rock is created when lava cools and hardens? A. igneous B. sedimentary C. metamorphic D. cement