College Biology Pretest

1. Each element has its own characteristic atom in which

The atomic weight is constant

The atomic number is constant

The mass number is constant

2. How many chromatids would a cell with 12 chromosomes have in the G2 phase of its cell cycle?

6

9

12

24

48

3. Sex-linked traits:

Are carried on an autosome but expressed only in males

Are coded for by genes located on a sex chromosome

Are always inherited from the mother in mammals and fruit flies

Are the same as sex-influenced traits

4. A sodium ion (Na+) contains 10 electrons, 11 protons, and 12 neutrons. What is the atomic number of sodium?

10

11

12

23

33

5. If the nucleotide sequence of one strand of a DNA helix is GCCTAA, what would be the sequence on the complimentary strand?

GCCTAA

CGGAUU

CGGATT

ATTCGG

TAAGCC

6. The longest part of the cell cycle is:

Prophase

G1 phase

G2 phase

Interphase

7. Carriers of a genetic disorder:

Are indicated by solid symbols on a family pedigree

Will produce children with that disease

Are heterozygotes for the gene that can cause the disorder

Have a homozygous recessive genotype

8. Homologous chromosomes:

Have idenitcal genes

Have genes for the same traits at the same loci

Are found in gametes

Seperate in meiosis II

9. Ions diffuse across membranes down their:

Electrochemical gradient

Electrogenic gradient

Electrical gradient

Osmotic gradient

10. Plants store most of their energy as:

Glucose

Glycogen

Starch

Sucrose

Cellulose

11. Contractile elements of muscle cells are:

Intermiediate filaments

Centrioles

Microtubules

Actin filaments

Fibronectins

12. Adding a base to a solution would:

Raise the pH

Lower the pH

Decrease the hydrogen ion concentration

Do both a and c

Do both b and c

13. Temperature is a measure of:

Specific heat

Average kinetic energy of molecules

Total kinetic energy of molecules

Celsius degrees

Joules

14. A 1:1 phenotypic ratio in a testcross indicates that:

The alleles are dominant

The dominant phenotype parent was a heterozygote

The alleles segregated independently

The alleles are codominant

15. How many "turns" of the Calvin Cycle are required to produce one molecule of glucose?

1

2

3

6

12

16. The ultrastructure of a chloroplast could be seen best using:

Transmission electron microscope

Scanning electron microscope

Phase-contrast light microscope

Fluorescence microscope

17. Transformation involves:

The uptake of external genetic material, often from one bacterial strain to another

The creation of a strand of RNA from a DNA molecule

The infection of bacterial cells by phages

The replication of DNA along the lagging strang

18. A planet cell placed in a hypotonic environment will:

Plasmolyze

Shrivel

Become turgid

Become flaccid

Lyse

19. A son inherits color blindness from his:

Mother

Father

Mother only if she is color blind

Father only if he is color blind

Mother only if she is not color blind

20. Which of the following is mismatched with its location?

Light reactions -- grana

Electron transport chain -- thylakoid membrane

Calvin cycle -- stroma

ATP synthase -- double membrane surrounding chloroplast

Splitting of water -- thylakoid space

21. The DNA of an organism has thymine as 20% of its bases. What percentage of its bases would be guanine?

20%

30%

40%

60%

80%

22. The restoration of the diploid chromsome number after halving in meiosis is due to:

Synapsis

Fertilization

Mitosis

DNA replication

Chiasmata

23. Translocation involves the transfer of genetic material by means of:

Plamids

Bacteriophages

Free DNA fragments

Conjugation

24. A signal molecule that binds to a plasma-membrane protein functions as a:

Ligand

Second messenger

Protein phosphatase

Protein kinase

Receptor protein

25. Each water molecule is capable of forming:

One hydrogen bond

Three hydrogen bonds

Four hydrogen bonds

One covalent bond and two hydrogen bonds

One covalent bond and three hydrogen bonds