Which invertebrate animal group is characterized by having a closed circulatory system?

A) Echinodermata
B) Annelida
C) Platyhelminthes
D) Nematoda
E) Arthropoda


B

Biology & Microbiology

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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.

Biology & Microbiology

HIV inserts its genome into the host cell's DNA

a. True b. False

Biology & Microbiology

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).

Biology & Microbiology

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

Biology & Microbiology