1. which of the following is always single-stranded?
a. messenger rna (mrna)
b. double-stranded rna (dsrna)
c. dna
d. dna and rna
(obviously its not b.)
2. which of the following is a difference between dna and rna?
a. most types of rna are double-stranded
b. rna contains lipids
c. they have different sugars
d. rna has thymine
3. which of the following bases are found in rna but not in dna?
a. uracil
b. guanine
c. adenine
d. cytosine
i'm pretty sure 3 is a. but i want to be sure.

The questions below will determine which restriction enzyme should be used to make a plasmid that contains both an intact vgp gene and a functional ampr gene. answer questions 1–4 by selecting from the answer choices on the left. drag the correct answer to the right of each question.

Transmission electron microscope are best for viewing a) microorganisms in pond water b) internal organs of a mouse c)internal structures of a cell d) surface features of a specimen

Ineed to get this test done which of the following statements is correct in hour our immune system responds to a potential pathogen? a.) the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. b.) b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c.) the adapted immune system will call on the innate immune system to destroy the pathogen. d.) the t-cells in the adapted immune systems are the first to recognize the pathogen