Lab Mid: Notes Flashcards
what causes surface tension of water,
attration of water molecules at the surface of the water
Which atom in water is positive? negitive?
H+, O-
What is pH the measure of
the acidity of the solution
Solutions with a pH lower than 7 are considered _____ while ones with greater pH are considered _______
acidic, basic
What do buffers do
Buffers help to maintain pH at a constant value in living organisms
What makes up a buffer
a weak acid and a weak base
What is a conjugate base
a base that is formed when an acid loses its H+ (H+ is the ‘acidic’ part of the molecule
What is a polymer composed of
monomers
What 4 classes of organic molecules make up most living organisms
carbohydrates, proteins, lipids, and nucleic acids
What are indicator solutions
solutions that will chance colors when a specific substance is detected
When a color reaction occurs in an indicator solution we call ths a ______ result
positive
When no color reaction occurs in an indicator solution we call ths a ______ result
negitive
If we include samples that we know will give a postive result we call it:
positive control
If we include samples that we know will give a negative result we call it:
negative control
__________ ________ tests for the presence of simple sugars or monosaccharides which have free ketone or aldehyde functional groups
Benedicts reagent
What does benedicts reagent test for
the presence of simple sugars or monosaccharides which have free ketone or aldehyde functional groups
What color represents a negative result in a benedicts reagent? positive?
neg: blue
Pos: reddish-orange
What kind of sugar will not cause a a color change with benedicts reagent
Sucrose (table sugar) is a disaccharide and therefore will not prompt a positive result
___________ ____________ will detect large carbohydrates called staches
Iodine-Potassium Iodide (I2KI)
Iodine-Potassium Iodide (I2KI)
detects large carbohydrates called staches
What color represents a negative result in a Iodine-potassium iodide? positive?
Neg: amber/dark brown
Pos: black-blue color
______ _______ tests for the presence of peptide bonds in proteins
Biurets reagent
What does Biurets reagent test for
the presence of peptide bonds in proteins
What color represents a negative result in a biurets reagent? positive?
Neg: light blue
Pos: Darker purple
Will individual amino acids in the solution react positivly with Biurets reagent? why or why not
No, they are not attched to another amion acid by peptide bonds
______ __ tests for the presence of lipids
Sudan IV
What does Sudan IV
tests for the presence of lipids
What color represents a negative result in a Sudan IV? positive?
Neg: yellow-pink color
Pos: strong red
What is one function of red blood cells
transport O and nutrience through the body
What is one function of white blood cells
fighting bacteria and infection
What is unique about the structure of red blood cells relative to other eukaryotic cells?
it has no nucleus
What is unique about the nuclei seen in white blood cells
they are multilobed/segmented which makes it look like it has many under a microscope
What is the function of sketetal muscle cells?
Moving muscles (contracting)
How many nuclei do sketetal muscle cells have
many
Would you expect a skeletal muscle to produce alot fo protein? why or why not?
alot since it requires alot of movement and energy
would you expect a skeletal musecle cell to have more mitochondria than other cell types? why or why not?
More, it needs alot of energy
What is unique about the function of sperm
meant for alot of movement and reproduction
Which organelle can be seen on sperm that was not observed in previous cell types? why does it need this?
flagella, it needs it for quick movement
Do spern have a nucleus? if so, where?
yes, in the head
Whould you expect a sperm cell to have a relatively low or high number of mitochondria compared to other cells
high, it requires alot of movement
What is the funciton of squamous cells? how does the shape of squamous cells contribute to their function?
protection from the outside world. they are wide and flat
How many nuclei do squamous cells have
one
What is unique about the fucntion fo a nerve cell
Send and receive signals from your brain
What is unqie about the shape of a nerve cell
It is star shaped with arms reaching out to connect to other cells
What organelles are found in plant cells that are not found in animal cels? can you see them with the microscope?
cell wall, yes
What is unique about the surrounding structure of plant cells? why would they need this?
cell wall, for structure and support and to keep rigidity
Do plant cells have a cell membrane? mitochondria?
yes,
Regarding size, how do prokaryotic cells compare to the size of eukaryotic cells?
Prokariotic cells are smaller
How many nuclei do prokaryotic cells contain
None, they have a nucleiod region
do prokaryotic cells have mitochondria
nah
Do prokaryotic cells have a cell membrane? wall?
yes
do prokaryotic cells have DNA
yes
Do bacteria have a nucelus
no
Do bacteria have membrane bound organelles
no
What shape is coccus bacteria? bacillus?
Coccus: round
Bacillus: rod
what does Staphylo imply about a bacteria grouping pattern? Strepto?
Staphylo: Clusters
Strepto: Chains
What is the shape of Clusters of round bacteria
staphylo coccus
What is the shape of clusters of rod bacteria
staphylo bacillus
What is the shape of chains of round bacteria
Strepto Coccus
What is the shape of chains of rod bacteria
Strepto Bacillus
Most bacteria have an outer cell wall made of a polymer of sugars and proteins called ________-
peptidoglycan
What is peptidoglycon
a polymer of sugars and proteins that make up the outer cell wall of some bacteria
What is a gram positive bacteria
Bacteria with a cell wall composed of up to 90% peptidoglycan
What is a gram negitive bacteria
Bacteria with a cell wall composed of only about 20%. Gram negitive bacteria will have a second, outermembrane made of phospholipids.
What is the order of reagents in gram staining procedure and what does each step basically do
Crystal violet (purple dye), iodine (mordant), alcohol (decolorization), safranin (counterstain)
What color is a gram positive bacteria? negitive?
Pos:purple
Neg: pink
What does crystal violet stain?
gram pos and neg
What does iodine/mordant do in a gram stain?
it binds the crystal violent to the cytoplasm
What does decolorizer/alcohol do in a gram stain
Drills a hole in the thin layer of peptidoglycan of gram neg, causing the purple to leave (it doesn’t affect pos because the peptidoglycan is thick and only becomes less permiable)
What does counterstain/Safranin do in a gram stain
stain the decollorized (neg) bateria pink
What process drives solutes to move about in a solution so that the concetration of each individual solute is the same throughtout the entire solution
diffusion
What is the goal of diffusion
equalibrium
Cell membranes contain channels and pumps that specifically allow only certain substances to cross, making the membrane _____-
semipermeable
Solutes that have channels (not pumps) let solutes move ______ into or out of cells ______ the solutes concentration gradient
passively, down
What solution has the same amount of solute compared to the cytoplasm
isotonic
What solution has more solute compared to the cytoplasm
Hypertonic
What solution has less solute compared to the cytoplasm
Hypotonic
What is it called when cells swell and burst
Lyse
What is it called when cells shrivel
crenate
What solution do plant cells prefer
Hypotonic
What is the NaCl concentration for a red blood cell
0.90%
What is the glucose concentration for a red blood cell
5%
an ______ is a protein that acts as a catalyst
enzyme
the intial energy investment needed to strech the bonds so they can break more easily is called
eactivation energy
What is the release of chemical energy stored in food
Cellular respiration
Where does cellular respiration take place
Cytoplasm and mitochondria of eukaryotic cells
what is the typical size of yeast
4um
fermentation is ____ respiration
anaerobic
Cellular respiration is _______ respiration
aerobic
