BIOL 204 LECTURE EXAM 2 ACTUAL
EXAMINATION 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
⫸ chitin Answer: •fibrous substance consisting of polysaccharides and
forming the major constituent in the exoskeleton of arthropods and the
cell walls of fungi.
⫸ absorptive heterotroph Answer: •an organism (usually a fungus) that
obtains its food by secreting digestive enzymes into the environment to
break down large food molecules, then absorbing the breakdown
products.
⫸ hyphae Answer: •each of the branching filaments that make up the
mycelium of a fungus.
⫸ septa Answer: Cross walls form compartments
⫸ coenocytic Answer: Hyphae that do not have septa
⫸ mycelium Answer: •A mass of filamentous hyphae that form the
body of a fungus.
,⫸ yeast Answer: any unicellular fungus that reproduces vegetatively by
budding or fission, including forms such as candida that can cause
disease.
⫸ mycorrhizae Answer: •a fungus which grows in association with the
roots of a plant in a symbiotic or mildly pathogenic relationship.
⫸ protists (protozoa) Answer: Single celled eukaryotic organisms that
can be animal-like, plant-like, fungi-like, or parasitic which means they
live on or in another organism causing harm
⫸ size of eukaryotes Answer: 100 to 10,000 times larger than
prokaryotes
⫸ eukaryotic complex/dynamic cytoskeleton Answer: allows the cell to
change shape and move things around within the cell.
⫸ eukaryotic nucleus Answer: n-folding of the cell membrane
surrounded the cell's DNA, compartmentalizing it
⫸ mitochondria (powerhouse of the cell) Answer: Where cellular
respiration takes place in aeukaryotic cell, generating chemical energy
(ATP).
, ⫸ endosymbiotic theory Answer: mitochondria originated when an
ancestral bacterium took up residence inside an ancestral eukaryotic cell
about 2 billion years ago.
⫸ chloroplasts Answer: he organelles in eukaryotes where
photosynthesis takes place (glucose and oxygen given off as a
byproduct).
⫸ photosynthetic eukaryotes Answer: chlorophyll contained in the
chloroplasts
⫸ primary endosymbiosis Answer: process similar to acquisition of
mitochondria, but in this case, the ancestral heterotroph engulfed a
photosynthetic cyanobacterium. Over time, the symbionts became very
dependent on one another. Cyanobacterium allowed for a heterotrophic
cell to make its own organic carbon compounds from inorganic CO2
⫸ secondary endosymbiosis Answer: another kind of horizontal
transfer. It is the spread of chloroplasts to other, and not necessarily
closely related eukaryotic lineages. The chloroplasts of these taxa have
more than two membranes surrounding them.
⫸ ingestion (protist) Answer: some protists are large enough to
surround and ingest other protists through engulfment by long, fingerlike
projections called pseudopodia
EXAMINATION 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
⫸ chitin Answer: •fibrous substance consisting of polysaccharides and
forming the major constituent in the exoskeleton of arthropods and the
cell walls of fungi.
⫸ absorptive heterotroph Answer: •an organism (usually a fungus) that
obtains its food by secreting digestive enzymes into the environment to
break down large food molecules, then absorbing the breakdown
products.
⫸ hyphae Answer: •each of the branching filaments that make up the
mycelium of a fungus.
⫸ septa Answer: Cross walls form compartments
⫸ coenocytic Answer: Hyphae that do not have septa
⫸ mycelium Answer: •A mass of filamentous hyphae that form the
body of a fungus.
,⫸ yeast Answer: any unicellular fungus that reproduces vegetatively by
budding or fission, including forms such as candida that can cause
disease.
⫸ mycorrhizae Answer: •a fungus which grows in association with the
roots of a plant in a symbiotic or mildly pathogenic relationship.
⫸ protists (protozoa) Answer: Single celled eukaryotic organisms that
can be animal-like, plant-like, fungi-like, or parasitic which means they
live on or in another organism causing harm
⫸ size of eukaryotes Answer: 100 to 10,000 times larger than
prokaryotes
⫸ eukaryotic complex/dynamic cytoskeleton Answer: allows the cell to
change shape and move things around within the cell.
⫸ eukaryotic nucleus Answer: n-folding of the cell membrane
surrounded the cell's DNA, compartmentalizing it
⫸ mitochondria (powerhouse of the cell) Answer: Where cellular
respiration takes place in aeukaryotic cell, generating chemical energy
(ATP).
, ⫸ endosymbiotic theory Answer: mitochondria originated when an
ancestral bacterium took up residence inside an ancestral eukaryotic cell
about 2 billion years ago.
⫸ chloroplasts Answer: he organelles in eukaryotes where
photosynthesis takes place (glucose and oxygen given off as a
byproduct).
⫸ photosynthetic eukaryotes Answer: chlorophyll contained in the
chloroplasts
⫸ primary endosymbiosis Answer: process similar to acquisition of
mitochondria, but in this case, the ancestral heterotroph engulfed a
photosynthetic cyanobacterium. Over time, the symbionts became very
dependent on one another. Cyanobacterium allowed for a heterotrophic
cell to make its own organic carbon compounds from inorganic CO2
⫸ secondary endosymbiosis Answer: another kind of horizontal
transfer. It is the spread of chloroplasts to other, and not necessarily
closely related eukaryotic lineages. The chloroplasts of these taxa have
more than two membranes surrounding them.
⫸ ingestion (protist) Answer: some protists are large enough to
surround and ingest other protists through engulfment by long, fingerlike
projections called pseudopodia
