module 17

protein

protein

large, complex polymer composed of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur

virus

nonliving strand of genetic material within a protein coat

Why are viruses considered nonliving?

• Have no organelles to take in nutrients or use energy​

• Cannot make proteins​

• Cannot move​

• Cannot replicate on their own​

capsid

outside layer of all viruses

What happens to the lytic cycle?

the host cell makes many copies of the viral RNA or DNA

What happens to the lysogenic cycle?

viral DNA integrates into a chromosome in a host cell

Retroviruses have…

have RNA instead of DNA for their genetic material

prion

protein that can cause infection or disease

example of prion

CJD

What does CJD result in?

cells in brain burst; spaces in brain

archaea environments

• halophiles (salt-loving)​

• methanogens (use CO2 and give off methane)​

• thermoacidophiles (high temperature, low pH)​

anaerobic cannot tolerate…

oxygen

Prokaryotes

microscopic, unicellular organisms

capsule

surrounds or encloses something else

Pili

submicroscopic hair-like structures made of protein

Binary fission

the asexual division of one cell into two identical cells

conjugation

two prokaryotes attach to each other and exchange genetic information​

Heterotrophs​ cannot…

synthesize their own food

Photoautotrophs

gain energy through photosynthesis

​Chemoautotrophs

break down and release inorganic compounds that contain nitrogen or sulfur

Endospores

dormant cells produced in response to harsh environmental conditions