BIO 51 LAB EXAM 2 FINAL (NEW) ADVANCED(2025/2026) | ACTUAL
EXAM QUESTIONS WITH DETAILED ANSWERS AND PRACTICE EXAM |
LATEST UPDATED AND VERIFIED FOR GUARANTEED A+
Bio 51 Lab Exam 2
What does the crystal violet stain do?
- stains the bacteria purple
What does the lugol's solution do?
- sets the stain
What does the alcohol/acetone do?
- destains the gram-negative bacteria
What does the safranin do?
- stains the gram-negative bacteria
convergent evolution
- when species independently evolved similar structures in response to similar environments or ways of
life, not because they share a recent common ancestor
ex: wings of bats and birds, shape of dolphins and fish, sugar gliders and flying squirrels
binary fission
- A form of asexual reproduction in which one cell divides to form two identical cells
- the cell duplicates its components and divides into two daughter cells
streak plate method
- a method of isolating a culture by spreading microorganisms over the surface of a solid culture medium
bioindicators
- when biological organisms are used to assess the condition of habitats
relative abundance
- the proportion each species represents of all individuals in the community
taxon (taxa)
- consists of a group of organisms that are phylogenetically related
- an order, family, genus, species, etc
taxa richness
- the total number of taxa in a sample
- often used as a measure of the diversity within a sample
- higher richness values are correlated with greater habitat diversity and higher water quality conditions
Simpson's Index of Diversity
,- represents the probability that two individuals, randomly selected from the sample, belong to different
taxa
- a simple metric that gives values ranging from 0-1
- the greater the index value, the greater the sample diversity
Simpson's Index of Diversity formula
1 - ∑(ni/N)^2
ni (SID)
- the total number of organisms of each particular taxon i
N (SID)
- the total number of organisms of all taxa
% EPT
- the percentage of a sample comprised of Ephemeroptera, Plecoptera, and Trihoptera
What does EPT % tell us?
- EPT are generally associated with clean, high quality streams
- members of these taxa are known to be sensitive to pollution and low water quality
% EPT formula
(total # of EPT individuals/total # of individuals in the entire sample) X 100
taxonomy
- the field devoted to the classification of organisms
taxonomic system
- devised by carolus linneaus
- a hierarchical system since organisms are grouped into ever more inclusive categories from species up
to kingdom
dorsal vessel (earthworm)
- a major blood vessel that runs along the dorsal surface of the worm
clitellum (earthworm)
- situated near the anterior end
- is involved in making a gelatinous egg casing during reproduction
pharynx (earthworm)
- the region between the mouth and esophagus
seminal vesicles (earthworm)
- what sperm matures into (larger)
seminal receptacles (earthworm)
- where sperm is received (spherical)
aortic arches (earthworm)
- dark, ring-like structures of the heart
- pump blood throughout the body
- surround the esophagus
, esophagus (earthworm)
- the tube that transports food from the pharynx to the crop
septa (earthworm)
- membranous structures that separate each segment
crop (earthworm)
- stores food (soil)
gizzard (earthworm)
- muscular and contains small rocks
- grind and mechanically digest food
intestine (earthworm)
- the site of chemical digestion and absorption of nutrients
- cells in the intestine secrete digestive enzymes
anus (earthworm)
- where feces is removed
alimentary canal
- digestive tube that extends from the mouth to the anus
antennae (grasshopper)
- sensory appendages
compound eyes (grasshopper)
- eyes that contain many lenses and are especially keen at sensing movement
- have three ocelli function as motion detectors
homologous traits
- similar structures, or inherited traits, that species share from the same common ancestor
homology
- similarity resulting from common ancestry
branch point (node)
- the point at which two lines separate on a phylogenetic tree
- indicates when a particular lineage split
convergent evolution
- when species independently evolved similar structures in response to similar environments or ways of
life, not be
analogous traits
- similar characteristics resulting from convergent evolution, therefore not derived from a common
ancestor
EXAM QUESTIONS WITH DETAILED ANSWERS AND PRACTICE EXAM |
LATEST UPDATED AND VERIFIED FOR GUARANTEED A+
Bio 51 Lab Exam 2
What does the crystal violet stain do?
- stains the bacteria purple
What does the lugol's solution do?
- sets the stain
What does the alcohol/acetone do?
- destains the gram-negative bacteria
What does the safranin do?
- stains the gram-negative bacteria
convergent evolution
- when species independently evolved similar structures in response to similar environments or ways of
life, not because they share a recent common ancestor
ex: wings of bats and birds, shape of dolphins and fish, sugar gliders and flying squirrels
binary fission
- A form of asexual reproduction in which one cell divides to form two identical cells
- the cell duplicates its components and divides into two daughter cells
streak plate method
- a method of isolating a culture by spreading microorganisms over the surface of a solid culture medium
bioindicators
- when biological organisms are used to assess the condition of habitats
relative abundance
- the proportion each species represents of all individuals in the community
taxon (taxa)
- consists of a group of organisms that are phylogenetically related
- an order, family, genus, species, etc
taxa richness
- the total number of taxa in a sample
- often used as a measure of the diversity within a sample
- higher richness values are correlated with greater habitat diversity and higher water quality conditions
Simpson's Index of Diversity
,- represents the probability that two individuals, randomly selected from the sample, belong to different
taxa
- a simple metric that gives values ranging from 0-1
- the greater the index value, the greater the sample diversity
Simpson's Index of Diversity formula
1 - ∑(ni/N)^2
ni (SID)
- the total number of organisms of each particular taxon i
N (SID)
- the total number of organisms of all taxa
% EPT
- the percentage of a sample comprised of Ephemeroptera, Plecoptera, and Trihoptera
What does EPT % tell us?
- EPT are generally associated with clean, high quality streams
- members of these taxa are known to be sensitive to pollution and low water quality
% EPT formula
(total # of EPT individuals/total # of individuals in the entire sample) X 100
taxonomy
- the field devoted to the classification of organisms
taxonomic system
- devised by carolus linneaus
- a hierarchical system since organisms are grouped into ever more inclusive categories from species up
to kingdom
dorsal vessel (earthworm)
- a major blood vessel that runs along the dorsal surface of the worm
clitellum (earthworm)
- situated near the anterior end
- is involved in making a gelatinous egg casing during reproduction
pharynx (earthworm)
- the region between the mouth and esophagus
seminal vesicles (earthworm)
- what sperm matures into (larger)
seminal receptacles (earthworm)
- where sperm is received (spherical)
aortic arches (earthworm)
- dark, ring-like structures of the heart
- pump blood throughout the body
- surround the esophagus
, esophagus (earthworm)
- the tube that transports food from the pharynx to the crop
septa (earthworm)
- membranous structures that separate each segment
crop (earthworm)
- stores food (soil)
gizzard (earthworm)
- muscular and contains small rocks
- grind and mechanically digest food
intestine (earthworm)
- the site of chemical digestion and absorption of nutrients
- cells in the intestine secrete digestive enzymes
anus (earthworm)
- where feces is removed
alimentary canal
- digestive tube that extends from the mouth to the anus
antennae (grasshopper)
- sensory appendages
compound eyes (grasshopper)
- eyes that contain many lenses and are especially keen at sensing movement
- have three ocelli function as motion detectors
homologous traits
- similar structures, or inherited traits, that species share from the same common ancestor
homology
- similarity resulting from common ancestry
branch point (node)
- the point at which two lines separate on a phylogenetic tree
- indicates when a particular lineage split
convergent evolution
- when species independently evolved similar structures in response to similar environments or ways of
life, not be
analogous traits
- similar characteristics resulting from convergent evolution, therefore not derived from a common
ancestor
