How can we help?

You can also find more resources in our Help Center.

99 terms

Lab Practical

STUDY
PLAY
What are the two types of data?
qualitative and quantitative
What is name of the scientific measurement system.
metric OR System International (SI)
Convert 250 mL to liters
.25 L
Microscope Parts
eyepiece, revolving nosepiece, objective, stage, base, observation tube, stand (arm), specimen holder (stage clip), condenser, main switch, sliding control lever, fine adjustment knob, soars adjustment knob, tension adjustment knob, tension adjustment ring, observation tube clamping screw, interpupillary distance scale, diopter adjustment ring
low-power magnification
40X
medium-power magnification
100X
high-dry magnification
400X
oil-immersion magnification
1000X
orientation of images with a compound microscope
upside down or backwards
orientation of images with a dissection scope
top and bottom
Explain why some microscopes are called COMPOUND microscopes, but others are called dissection scopes
the compound microscopes have 2 lenses - the ocular lens and objective lens
differences between compound microscopes and dissection scopes
dissection scope's stage is farther from the objective lens; dissection scope is for large specimens and compound is for smaller specimens; dissecting microscope usually has less magnification than a compound microscope
Explain how to make a wet-mount.
Place specimen on slide, add a drop or 2 of water, hold coverslip at 45 degree angle over specimen, then let it fall on the specimen.
What are prokaryotes missing in their cytoplasms?
cytomembrane system and organelles
Why do we stain objects to be observed with the microscope?
to differentiate different types of organisms or to view specific parts of organisms
How do scientists use the Gram stain?
It is based on the chemical and physical properties of a cell wall. It detects peptidoglycan, which is present in a thick layer in Gram positive bacteria. A Gram positive results in a purple/blue color while a Gram negative results in a pink/red color.
What are some differences between plant and animal cells?
* Plant cells have chloroplasts unlike animal cells
* Plant cells have a cell wall unlike animal cells
* large central vacuole in plant cells
cell membrane
semipermeable, allowing some substances to pass into the cell and blocking others
cell wall
layer of cellulose fiber that give the cell most of its support and structure; bonds with other cell walls to form the structure of the plant
chloroplast
an elongated or disc-shaped organell containing chlorophyll; photosynthesis takes place in the chloroplasts
Gogli body
packages proteins and carbs into membrane-bound vesicles for "export" from the cell
granum (grana)
a stack of thylakoid disks within the chloroplast
mitochondrion
converts the energy stored in glucose into ATP for the cell
nucleolus
where ribosomal RNA is produced
nucleus
controls many of the functions of the cell (by controlling synthesis) and contains DNA (in chromosomes)
ribosome
small organelles composed of RNA-rich cytoplasmic granules that are sites of protein synthesis
rough endoplasmic reticulum
transport materials through the cell and produces proteins in sacks called cisternae
smooth endoplasmic reticulum
transport materials through the cell; contains enzymes and produces and digests lipids (fats) and membrane proteins; buds off from rough ER, moving the newly-made proteins and lipids to the Gogli body and membranes
thylakoid disk
where photosynthesis (the production of ATP molecules form sunlight) takes place
vacuole
helps maintain the shape of the cell
lysosome
where the digestion of cell nutrients takes place
vacuole
fills with food being digested and waste material that is on its way out of the cell
What is dialysis tubing?
selectively permeable material that provides a means to demonstrate the movement of substances through cellular membranes
Explain the difference between semipermeability and selective permeability.
semi-permeable membranes allow some particles to pass through and selectively permeable membranes choose what passes through
What is the testing solution for the presence of starch?
Iodine - Kl reagent
hypertonic
one solution containing greater concentration of solute relative to a second one
hypotonic
solution containing the lower concentration of solute molecules than another
isotonic
solutions containing equal concentrations of solute
What structure regulates what goes in and out of the cell?
membranes
What is an enzyme?
proteins that function as biological catalysts
In the potato lab, catechol was mixed with potato extract. The result was a brown color due to the presence of benzoquinone. This reaction was attempted with hydroquinone, as well.
*Which chemical is the substrate?
catechol + 1/2 O2
In the potato lab, catechol was mixed with potato extract. The result was a brown color due to the presence of benzoquinone. This reaction was attempted with hydroquinone, as well.
*Which chemical is the product?
benzoquinone
In the potato lab, catechol was mixed with potato extract. The result was a brown color due to the presence of benzoquinone. This reaction was attempted with hydroquinone, as well.
*What was being tested when hydroquinone was used?
if the enzyme catechol oxidase was able to catalyze the oxidation of 2 different but structurally similar substrates: catechol and hydroquinone
In the potato lab, catechol was mixed with potato extract. The result was a brown color due to the presence of benzoquinone. This reaction was attempted with hydroquinone, as well.
*Where is the enzyme?
in the potato extract
If you use a red filter with the spectroscope, what color(s) are absorbed by the filter?
red
If you use a blue filter with the spectroscope, what color(s) are reflected by the filter?
all other colors besides blue
Set up the formula and show a sample calculation for the Retardation Factor (Rf ).
Rf = distance traveled by pigment/distance traveled by solvent
Which stage of mitosis is the longest?
prophase
Name the order of the steps of the cell cycle.
G1, S, G2, prophase, metaphase, anaphase, telophase, cytokinesis
What is the mnemonic for memorizing the steps of the cell cycle?
PMAT
In what phase does crossing over occur?
prophase 1
What is the most obvious benefit of crossing over?
genetic variability
What is the name of the process that results in female gametes?
oogenesis
What is the name of the statistical test that you might conduct to determine whether your values are close enough to the expected values?
Chi-squared
Give the equation of Chi-squared
*X^2= ∑▒〖(O-E)〗^2/E
E = expected number of individuals
O = observed number of individuals
Suppose that brown eye color in laboratory rats is dominant to red eye color. A heterozygous male is mated to a homozygous recessive female.
*What are the phenotypes of the parents?
male has brown eyes; female has red eyes
Suppose that brown eye color in laboratory rats is dominant to red eye color. A heterozygous male is mated to a homozygous recessive female.
*What are the genotypes of the parents?
male - Bb
female - bb
Suppose that brown eye color in laboratory rats is dominant to red eye color. A heterozygous male is mated to a homozygous recessive female.
*What is the probability of producing red-eyed children?
1:1
Suppose that brown eye color in laboratory rats is dominant to red eye color. A heterozygous male is mated to a homozygous recessive female.
*What are the genotypes?
Bb and bb
Suppose that brown eye color in laboratory rats is dominant to red eye color. A heterozygous male is mated to a homozygous recessive female.
*What is the probability of producing brown-eyed children?
1:1
Explain the main cause of the most recent mass extinctions to hit Planet Earth.
dinosaurs disappeared because a giant meteor hit earth
What is biodiversity?
The variety of life in the world or in a particular habitat or ecosystem.
What are keystone species?
species that has a disproportionately large effect on its environment relative to its abundance
How many different animal species have been identified on Earth?
about 1,370,000
What animal species has had the most influence on creating change in the world biosphere? Explain.
If you removed all of the insects the entire biosphere would collapse.
Who is Linneaus?
"Father of Taxonomy"
How is the scientific name for each species written? Name the parts of the name.
with the first name (genus) capitalized and the second name (specific epithet) not capitalized; both are in italics
What is agar?
agar is a polymer made up of subunits of the sugar galactose
Where does agar come from?
it is a component of the cell walls of several species of red algae
How is agar used?
use is as a culture medium for various microorganisms, particularly for bacteria
Some bacteria, such as really salty water or hot springs and geysers. What is the name of the group that most of these bacteria that live in strange environmental conditions belong to?
Archaebacteria
What do we mean by the "animal-like protista"?
share traits that animals possess like being a heterotroph and being able to move to find food
What do we mean by the "plant-like protista"?
plant-like protista are autotrophic and produce oxygen
Protozoa are classified on the basis of what characteristic?
heterotrophic
Algae are classified on the basis of what characteristic?
photosynthetic protistans
Name the divisions of alga and examples of each.
*Euglenozoa - euglenoids
*Chrysophyta - diatoms
*dinoflagellata - dinoflagellates
*Rhodophyta - red algae
*Phaeophyta - brown algae
*Chlorophyta - green aglae
*Charophyta - desmids and stoneworts
purpose of mushroom cap
to grow gills
purpose of mushroom gills
to produce spores
purpose of mushroom spores
shoot out of the gills and mix with spores from other mushroom to reproduce
What are the Divisions of fungi?
Microsporidia, Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, Glomeromycota, Ascomycota, and Basidiomycota
How are the divisions of fungi distinguished from each other?
by parasites, saprobes, and mutualists
asymmetrical
cannot cut the body into 2 like halves
radial symmetry
any cut from the mouth to the other end through the center of the animal yields 2 like halves
bilateral symmetry
cut in only one plane, parallel to the main axis and dividing the body into right and left pieces, yields like halves
coelom
ventral cavity lined by tissue derived from mesoderm
pseudocoelom
ventral cavity where mesodermal lining is incomplete
primary germ layers
ectoderm, mesoderm, and endoderm
What phylum does the earthworm belong to?
Annelida
What class does the crawdad belong to?
Malacostraca
What class does the grasshopper belong to?
Insecta
crawdad male features
front 2 pairs of swimmerets enlarded for copulating and transferring sperm; opening of the sperm ducts at the bases of the 5th pair of walking legs
crawdad female features
seminal receptacle in the middle between the bases of the 4th and 5th pairs of walking legs and discs covering the oviducts at bases of 3rd pair
To what phylum and class does a hagfish belong?
P. Chordata; C. Myxini
To what phylum and class does a shark belong?
P. Chordata; C. Chondrichthyes
To what phylum and class does a perch belong?
P. Chordata; C. Actinopterygii
To what phylum and class does a frog belong?
P. Chordata; C. Amphibia
To what phylum and class does a rattlesnake belong?
P. Chordata; C. Reptilia
To what phylum and class does a pigeon belong?
P. Chordata; C. Aves
To what phylum and class does a rabbit belong?
P. Chordata; C. Mammalia