TXST DR. VARGAS BIO 1321 - EXAM 2
QUESTIONS AND ANSWERS 100% PASS
2026 EDITION
Characteristics of prokaryotes - ANS - smallest & simplest living things
- single-celled (cannot be seen w/naked eye)
- 3 common shapes: spherical, rod-shaped, spiral-shaped
- they live EVERYWHERE
- reproduce by binary fission
binary fission - ANS - single bacterium replicates DNA then divides in half
- asexual cell division producing identical copies (sometimes w/mutations)
- can occur as often as every 20 minutes
- fast reproduction=fast evolution
conjugation - ANS - exchange of genetic material between prokaryotes without reproduction
plasmid - ANS - small, circular piece of DNA located in the cytoplasm of many bacteria
- separate from main chromosome
differences between bacteria & archaea - ANS 1. molecular & structural differences
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, 2. archaea can produce methane
3. some bacteria (autotrophs) can undergo photosynthesis
- archaea = heterotrophs
4. some bacteria are pathogenic
5. bacteria contain peptidoglycan
- gram stains
6. some bacteria produce endospores or biofilms
heterotrophs - ANS organisms that cannot make their own food
autotrophs - ANS organisms that are able to make their own food
pathogens - ANS disease causing agents
peptidoglycan - ANS - layers carbohydrates linked by proteins
- forms a mesh-like layer around bacteria
- some bacteria also have an extra fatty layer covering
gram stains - ANS - tells whether the peptidoglycan is on the outside or covered by the extra
fatty layer
- gram positive = purple
- gram negative = pink/red (extra fatty layer)
biofilms - ANS communities of slime-secreting bacteria
endospores - ANS A thick-walled protective spore that forms inside a bacterial cell and resists
harsh conditions.
@COPYRIGHT 2026 ALLRIGHTS RESERVED 2
QUESTIONS AND ANSWERS 100% PASS
2026 EDITION
Characteristics of prokaryotes - ANS - smallest & simplest living things
- single-celled (cannot be seen w/naked eye)
- 3 common shapes: spherical, rod-shaped, spiral-shaped
- they live EVERYWHERE
- reproduce by binary fission
binary fission - ANS - single bacterium replicates DNA then divides in half
- asexual cell division producing identical copies (sometimes w/mutations)
- can occur as often as every 20 minutes
- fast reproduction=fast evolution
conjugation - ANS - exchange of genetic material between prokaryotes without reproduction
plasmid - ANS - small, circular piece of DNA located in the cytoplasm of many bacteria
- separate from main chromosome
differences between bacteria & archaea - ANS 1. molecular & structural differences
@COPYRIGHT 2026 ALLRIGHTS RESERVED 1
, 2. archaea can produce methane
3. some bacteria (autotrophs) can undergo photosynthesis
- archaea = heterotrophs
4. some bacteria are pathogenic
5. bacteria contain peptidoglycan
- gram stains
6. some bacteria produce endospores or biofilms
heterotrophs - ANS organisms that cannot make their own food
autotrophs - ANS organisms that are able to make their own food
pathogens - ANS disease causing agents
peptidoglycan - ANS - layers carbohydrates linked by proteins
- forms a mesh-like layer around bacteria
- some bacteria also have an extra fatty layer covering
gram stains - ANS - tells whether the peptidoglycan is on the outside or covered by the extra
fatty layer
- gram positive = purple
- gram negative = pink/red (extra fatty layer)
biofilms - ANS communities of slime-secreting bacteria
endospores - ANS A thick-walled protective spore that forms inside a bacterial cell and resists
harsh conditions.
@COPYRIGHT 2026 ALLRIGHTS RESERVED 2
