Answer Key for Assessment:

Part 1: Microarray Background and Technology:

  1. What is the relationship between DNA and RNA?

RNA is a copy of a specific sequence of DNA.

  1. True/False: DNA leaves the nucleus to be translated into proteins.

False, DNA never leaves the nucleus. Only RNA will leave the nucleus.

  1. Proteins are made in:
  1. The nucleus
  2. On the RNA
  3. Ribosomes
  4. Outside the cell

Answer: C

  1. True/False: Cells contain only the DNA that is relevant to their specific function.

False, all nucleated cells carry the full set of DNA.

  1. True/False: At any given time, not all the genes of a cell are active.

True, genes are turned on and off depending on the needs of the cell.

  1. DNA Microarray technology takes advantage of what natural occurrence?

Complimentary base pairing.

  1. DNA Microarrays are made of:
  2. Plastic
  3. Silicon
  4. Glass
  5. All of the above

Answer: D, all of the above

  1. What are DNA probes?

Fragments of gene sequences that are spotted onto a DNA chip.

  1. Why do mRNAs from the cell have to be made into cDNAs?

RNAs are not stable due to RNAses in the environment, cDNAs are stable.

  1. What is the name of the enzyme that converts RNA cDNA?

Reverse Transcriptase.

  1. Write out the cDNA copy of the RNA sequence: AUGCCAUUGAC

TACGGTAACTG

  1. What process allows the scientist to “see” which sequences have bound the chip?

Fluorescent labeling of the cDNA sequence.

  1. Which of the following will the cDNA sequence ATGCC hybridize to?
  2. TTCA
  3. ACGG
  4. CAGT
  5. TACC

Answer: B, ACGG

  1. Define hybridization

The process of a cDNA sample binding via complimentary base pairing to the DNA chip.

  1. How can the scientist tell if the sample has hybridized to a probe?

The probe that has bound the sample will be fluorescent.

  1. True/False: Using Microarray technology, a scientist can examine thousands of genes from multiple samples all at the same time.

True

  1. How can a scientist tell the difference between multiple samples run together?

They have to be labeled with different colored fluorescent probes.

Part 2: Coral Reef Biology

  1. Corals are members of which phylum?
  2. Cnidaria
  3. Porifera
  4. Platyhelmenthis
  5. Nematoda

Answer: A, Cnidaria

  1. True/False: Corals have true tissues, including distinct “gut” and brain.

False: Corals have true tissues, but no gut or brain.

  1. What is the function of cnidocytes?

To paralyze prey.

  1. Which type of reproduction (sexual or asexual) increases genetic variability and allows the coral to set-up in novel locations?

Sexual

  1. What type of environment houses coral reefs?

Warm, tropical waters.

  1. What does it mean to have a symbiotic relationship?

Both parties benefit.

  1. Describe the relationship between the coral and the zooxanthellae.

The coral protects the algae and provides the substrates of photosynthesis; the zooxanthellae are photosynthetic and provide the coral with glucose and oxygen as well as aid in the production of calcium carbonate.

  1. What is CaCO3?

Calcium carbonate (limestone) that is the exoskeleton of the coral and the framework of the reef.

  1. True/False: All corals build reefs.

False:Only hard corals build reefs.

  1. What species of coral are found around the Hawaiian Islands?

Lobe coral, finger coral and cauliflower coral.

  1. Describe coral bleaching.

Coral bleaching occurs when the coral ejects the zooxanthellae and lose their color; ie. Turn white or bleach.

  1. Why is it important that we protect and try to support the growth of coral reefs?

They are an important habitat for marine life and they are a draw for tourists.

Answer Key for Assessment
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