Which invertebrate animal group is characterized by having a closed circulatory system?
A) Echinodermata
B) Annelida
C) Platyhelminthes
D) Nematoda
E) Arthropoda
B
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Answer the following statements true (T) or false (F)
1. Prokaryotic genomes often contain a circular chromosome with hundreds of thousands of genes and highly repetitive DNA. 2. In humans, the genome is made up of 22 autosomes and 1 sex chromosome. 3. Some transposable elements contain a central region that encodes transposase, an enzyme that facilitates the actual transposition. 4. If a researcher determines that 25% of a liver cell's total genome encodes genes for metabolic enzymes, then he/she can conclude that metabolic enzymes make up 25% of the total protein composition of the cell. 5. A nerve cell and a muscle cell taken from the same individual would have two different sets of genes.
HIV inserts its genome into the host cell's DNA
a. True b. False
Phylogenetic trees are usually constructed using either a distance-based ________ approach, or a characteristic ________ approach.
Fill in the blank(s) with the appropriate word(s).
In a population of 50,000 diploid individuals, what is the probability that a new neutral mutation will ultimately reach fixation?
a. 0.001 b. 0.0001 c. 0.00001 d. 0.000001 e. 0.0000001