Science 9 Chapter 4 Practice Test

Multiple Choice

Identify the choice that best completes the statement or answers the question.

____ 1. A gene is

a. / another name for a chromosome.
b. / a section of DNA that codes for a specific protein.
c. / a tightly coiled strand of DNA.
d. / produced in the Golgi body.

____ 2. In the DNA molecule, the nitrogen bases are always found in pairs. The base A pairs with

a. / the base C. / c. / the base G.
b. / the base T. / d. / another base A.

____ 3. The “genetic code” is made up of

a. / the arrangement of sugar and phosphate groups along the DNA molecule.
b. / the sequence of bases along the DNA molecule.
c. / the pairs of chromosomes in a cell.
d. / the proteins that make up a particular stretch of DNA.

____ 4. A mutation causes a bacterial cell to begin producing a new protein. The mutation probably

a. / changed the number of chromosomes in the bacterial cell.
b. / led to a new combination of chromosomes in the bacterial cell.
c. / changed the sequence of nucleotides within part of the bacterial DNA.
d. / will not be passed on to daughter cells when the bacterial cell divides.

____ 5. Where in the cell are the chromosomes located?

a. / chloroplasts / c. / nucleus
b. / Golgi bodies / d. / vacuoles

____ 6. The endoplasmic reticulum is labelled on the diagram of the plant cell shown above. It is labelled as part number

a. / 1. / c. / 9.
b. / 2. / d. / 11.

____ 7. Part number 2 in the diagram of the green plant cell is responsible for making ribosomes. It is called the

a. / Golgi body. / c. / nucleus.
b. / nucleolus. / d. / vesicle.

____ 8. Part number 11 in the diagram of the green plant cell is referred to as the “powerhouse” of the plant cell. It is called the

a. / Golgi body. / c. / nucleus.
b. / mitochondrion. / d. / vesicle.

____ 9. Part number 6 in the diagram of the green plant cell is a specialized organelle that sorts and packages proteins for transport in the cell. It is called the

a. / Golgi body. / c. / nucleus.
b. / mitochondrion. / d. / vesicle.

____ 10. Part number 1 is the control centre of the cell. It is called the

a. / Golgi body. / c. / nucleus.
b. / mitochondria. / d. / vacuole.

____ 11. The type of mutation that benefits an individual

a. / never happens.
b. / is called a positive mutation.
c. / happens every time an individual produces new cells.
d. / happens only when a geneticist uses gene therapy.

____ 12. A neutral mutation

a. / does not affect the organism.
b. / never happens since all mutations affect an individual.
c. / cannot be transmitted to the next generation.
d. / will not be seen until two or three generations have been produced.

____ 13. Substances or factors that cause mutations in DNA are called

a. / bacteria. / c. / mutagens.
b. / diseases. / d. / mutations.

____ 14. When a cell is preparing to reproduce, the chromatin in the nucleus forms into

a. / chromosomes. / c. / genes.
b. / deoxyribonucleic acid. / d. / ribonucleic acid.

____ 15. The normal human cell carries

a. / 23 separate chromosomes. / c. / 46 separate chromosomes.
b. / 23 pairs of chromosomes. / d. / 46 pairs of chromosomes.

____ 16. Genes

a. / are small segments of DNA located at specific places on a chromosome.
b. / are specific arrangements of bases in the DNA.
c. / can vary in length from hundreds to thousands of bases.
d. / can be all of the above.

____ 17. One side of a gene segment is composed of the following bases: GTGCAATCGCTT. What would the bases on the other side of the ladder be?

a. / GTGCAATCGCTT / c. / CACGTTAGCGAA
b. / ACATGGCTATCC / d. / TGTACCGATAGG

____ 18. One side of a gene segment is composed of the following bases: AACGTCTGATCG. What would the bases on the other side of the ladder be?

a. / TTGCAGACTAGC / c. / CCATGAGTCGAT
b. / GGTACTCAGCTA / d. / AACGTCTGATCG

____ 19. A specific protein is produced when

a. / an RNA molecule brings the instructions to a ribosome.
b. / a DNA molecule brings a chemical message to a ribosome.
c. / a DNA molecule brings a chemical message to a Golgi body.
d. / a vesicle receives a chemical message from the endoplasmic reticulum.

____ 20. Gene mutation is

a. / a change in the arrangement of bases in a gene.
b. / always a bad thing for an organism.
c. / easily corrected with surgery.
d. / none of the above.

____ 21. When a gene mutation occurs

a. / one of the bases is left out of the sequence.
b. / one of the bases is substituted for another.
c. / a new base is added to the sequence.
d. / any of the above could have occurred.

____ 22. Which of the following are examples of mutagens?

a. / Cigarette smoke, X rays, and UV radiation.
b. / Cigarette smoke, pollutants such as pesticides, and some household chemicals.
c. / X rays, radiation, and some forms of industrial waste.
d. / All of the above are examples of mutagens.

____ 23. Treatment for mutations that alter the genes is called

a. / gene correction. / c. / genetic manipulation.
b. / gene therapy. / d. / genetic surgery.

____ 24. When mutations are corrected by inserting healthy genes, the result is

a. / the correct proteins are produced.
b. / the cell reproduces the new genetic material.
c. / healthy genes are inserted into the chromosomes.
d. / all of the above occur.

____ 25. What is the correct order for building a protein from a gene?

I / Ribosomes build the protein.
II / RNA is copied from the DNA in the nucleus.
III / RNA carrying the gene code is read by the ribosomes.
IV / RNA is sent out into the cytoplasm.
a. / II, IV, III, I / c. / II, III, IV, I
b. / III, I, II, IV / d. / I, IV, III, II

Completion

Complete each statement.

26. DNA is found in the form of long strands called ______.

27. Each strand of DNA is divided up into functional units called ______.

28. Each gene is responsible for coding for a particular ______.

29. A DNA molecule looks somewhat like a coiled ladder. The rungs (or steps) of the ladder are made up of ______.

Their names are : ______,______,______,

______

30. A DNA molecule looks somewhat like a coiled ladder. The sides of the ladder are made of phosphate and ______.

31. Within the cell, the DNA is found in the ______.

32. Mutations of the DNA within the nucleus of a cell can be caused by exposure to ______.

33. The cell part responsible for controlling the flow of materials into and out of the cell is the ______.

34. The message to produce a specific protein is carried from the DNA to the ribosome by means of ______.