Lecture 17 Flashcards Preview

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Flashcards in Lecture 17 Deck (26):
1

AIDS

symptoms and signs present during late stage HIV

2

bacteriophage / phage

A virus that
infects bacteria; also called a phage.

3

capsid

The protein shell that encloses a viral
genome. It may be rod-shaped, polyhedral,
or more complex in shape.

4

conjugation

In prokaryotes,
the direct transfer of DNA between
two cells that are temporarily joined.
When the two cells are members of different
species, conjugation results in horizontal gene transfre

5

F factor

In bacteria, the DNA segment that
confers the ability to form pili for conjugation
and associated functions required
for the transfer of DNA from donor to
recipient. The F factor may exist as a plasmid
or be integrated into the bacterial
chromosome.

6

generalized transduction

In generalized transduction, a small piece of the host cell?s degraded DNA is
packaged within a capsid, rather than the phage genome

7

HIV

human immunodeficiency virus)
The infectious agent that causes AIDS.
HIV is a retrovirus.

8

lysogenic cycle

A type of
phage replicative cycle in which the viral
genome becomes incorporated into the
bacterial host chromosome as a prophage, is
replicated along with the chromosome, and
does not kill the host.

9

lytic cycle

A type of phage replicative
cycle resulting in the release of new phages
by lysis (and death) of the host cell.

10

nucleoid

Nucleus Like

11

operon

A unit of genetic function
found in bacteria and phages, consisting of
a promoter, an operator, and a coordinately
regulated cluster of genes whose products
function in a common pathway.

12

plasmid

A small, circular, doublestranded
DNA molecule that carries accessory
genes separate from those of a bacterial
chromosome; in DNA cloning, can be used
as a vector carrying up to about 10,000 base
pairs (10 kb) of DNA.

13

prion

Prions are infectious proteins that spread a diseas

14

prophage

A phage genome that has
been inserted into a specific site on a bacterial
chromosome.

15

provirus

A viral genome that is permanently
inserted into a host genome.

16

R plasmid

A bacterial plasmid carrying genes
that confer resistance to certain antibiotics.

17

retrovirus

an important class of
cancer-causing viruses

18

reverse transcriptase

An
enzyme encoded by certain viruses (retroviruses)
that uses RNA as a template for DNA
synthesis.

19

specialized transduction

Specialized transduction occurs via a temperate phage, when the viral genome that is excised from the chromosome it sometimes takes with it a small region of adjacent bacterial DNA on the viral genome

20

temperate phages

Phages capable of using both modes
of replicating within a bacterium are called temperate phages

21

transduction

A process in which phages
(viruses) carry bacterial DNA from one bacterial cell to another. When these two
cells are members of different species, transduction
results in horizontal gene transfer.
(2) In cellular communication, the conversion
of a signal from outside the cell to a
form that can bring about a specific cellular
response; also called signal transduction.

22

transformation

The conversion of a
normal animal cell to a cancerous cell.

23

transposon

transposable element that
moves within a genome by means of a DNA
intermediate.

24

vaccine

A harmless variant or derivative
of a pathogen that stimulates a host?s immune
system to mount defenses against the
pathogen.

25

viral envelopes

Virus' outer membrane

26

virulent virus

reproduce only by a lytic cycle