lab test 1 Flashcards
eyepiece (ocular) function
the uppermost lens or series of lenses through which a specimen is viewed. Most have a magnification of 10x
Body function
holds the nose piece at one end and includes the draw tube
Arm function
serves as a handle
Nose piece function
revolves and holds the objectives
Objective function
lower lenses attached to the nose piece. The magnification of each objective is stamped on the housing of the objective
Stage clip function
secures the slide in place
stage function
platform on which slides are placed. some microscopes have a mechanical stage to accurately control the movement of the slides
Fine Focus adjustment knob function
used to adjust the specimen into final focus
focus adjustment knob (coarse) function
used to adjust the microscope on scanning and low power only
Condensor function
a lens system found beneath the stage, used to focus light on the specimen
collector lens with field diaphram function
regulates light entering the microscope. usually is controlled by mechanical lever or rotating disc
light source (illuminator) function
serves as the source of illumination for the microscope
Base function (micro)
the supportive portion of the microscope, which rests on the laboratory table
wet mount slides
has the specimen mounted on a liquid (usually water) and then covered with a cover glass
prepared slides
has a permanantly attached cover glass and the specimen is usually stained
ionic bonds
form when two atoms are so unequal in their attraction for valence electrons that one atom strips an electron completely from the other
hydrogen bonds
form when a hydrogen atom that is already covalently bonded to one electronegative atom is attracted to another electronegative atom. Temporary and weak individually, collectivly strong
Nonpolar covalent bonds
involve equal sharing of electrons
polar covalent bonds
involve unequl sharing of electrons
covalent bonds
result from the sharing of electrons
Acid
a substance that yields (donates) a hydrogen ion in a solution
Characteristics of acids
- contribute one of more hydrogen atoms to a solution when the dissaciciate in water
- have a sour taste
- may be corrosive or poisonous
- may react with certain metals to liberate hydrogen gas
- neutralize bases
- affect the color of certain indicators
Base
commonly known as alkaline. release hydroxide ions in a solution
Characteristics of bases
- release OH- in a solution
- have a bitter taste
- feel sliperly
- may be corrossive or poisonous
- neuatalize acids
- affect the color of certain inidcators
How to test for acids
- turn blue litmus red
- turn phenothalein colorless
- turn methyl orange indicators red
- pH paper
- pH meter
- cabbage extract
How to test for bases
- turn red lithmus blue
- turn phenothalien pink
- turn methyl orange indicators yellow
- cabbage extract
- pH paper
- pH meter
Use of antacids
neutralize acids
Phospholipids
two fatty acids and a phosphate group are attached to a glycerol. Fatty acid tails are hydrophobic and phosphate and its attachments from a heads that is hydrophilic
Peptide bonds
amino acids are linked by peptide bonds. a peptide bond is a covalent bond that forms between the amino group of one amino acid and the carboxyl group of another amino acid
hydrocarbon
organic molecules consisting of only one carbon and hydrogen. undergo reactions that release a lot of energy
Saturated fat
consist of saturated fatty acids with the maximum number of hydrogen atoms
unsaturated fat
consist of unsaturated fatty acids that contain at least one double bond in the fatty acid chain. tend to be liquid at room temperature
Reducing sugars test/ carbohydrates
Benedicts
Starch test
Iodine
Lipids test
Sudan IV
lipid test
paper spot
Protein test
biuret
Why do we use water in tests
negative control group, there should be no result obtained from water
Explain cabbage test
plant material yields a specific color at a specific pH. Cabbage extract turns certain colors to determine acids and bases throughout the pH spectrum
Carbohydrates
organic compounds that contain carbon, hydrogen, and oxygen in a 1:2:1 ratio
Lipids
diverse organic compounds that include fats, waxes phospholipids and steroids. Insoluable in water and soluble in nonpolar compounds. Consist of mostly carbon and hydrogen with a few oxygen atoms
Proteins
Most numerous and complex molecules in living organisms. Provide support,/movement, storage, defense and regulation
Monosaccherides
molecules composed of three-to seven carbon atoms and their appropriate hydrogen and oxygen atoms
dehydration synthesis =/condensation
when two monosaccharides combine to form a double sugar (disacchardide)
Disaccharide
a double sugar formed through dehyrdation synthesis
Hydrolysis
disaccharides being broken down into their simple sugars
Polysaccharides
complex carbohydrates built from simple carbohydrates linked by dehydration synthesis
Starch
a storage polysaccharide that consists of glucose molecules in plants
gycogen
animal starch, highly branched glucose rich polysaccharide stored in the liver and skeletal muscles of animals
Chitin
a modified polysaccharide that is the main component of cell walls and of some fungi and the exoskeleton of insects and other arthropods
Why did we preform the phenopthalein experiment
looking for change in the baking soda (base) into an acid by using phenothalein. It shouldve turned pink to clear with the addition of CO2
Prokaryotic cells vs eukaryotic cells
Prokaryotic: smaller, lack membrane bound organelles, cytoplasm surrounded by a cell membrane and majority of the time has a cell wall, two kingdoms (archaebacteria and eubacteria)
Eukaryotic: larger and more structurally complex, has membrane bound nucleus and organelles, kingdoms (protista, plantae, fungi, and animalia)
Prokaryotic examples from lab
Oscilatoria
Archea
ancient prokaryotic cells, live in extreme conditions
Eubacteria
bacteria, such as staph
Basic shapes of eubacteria
round, rod, spiral
Eubacteria organelles
nucleoid, ribosomes, no membrane bound organelles
Eubacteria pili function
attach a bacterial cell to specific surfaces or to other cells
Eubacteria nucleoid function
houses DNA in the prokaryotic cell. Not membrane bound. May also contain RNA, enzymes and proteins for cellular processes
Eubacteria ribosome function
translate mRNA and protein synthesis
Eubacteria cytoplasm function
where the functions for cell growth, metabolism, and replication are carried out. contains cell structures such as ribosomes.
Eubacteria plasma membrane function
Acts as a permability barrier for most molecules
Eubacteria cell wall function
gives bacteria structural support
Eubacteria capsule function
protects cell from engulfment by eukaryotic cells. Contains water to prevent cell from drying out. It also helps the cell to adhere to surfaces
Eubacteria flagellum function
allows for bacterial movement
Protist classification system
A diverse group of eukaryotic cells that can be catagorized as being plant, animal, or fungi-like
Fungi definition
a diverse group of mostly multicellular heterotrophic organisms
Fungi examples
ring worm, yeast
Plant cell wall function
a cellulose envelope that provides protection and shape
Plant plasma membrane function
a phospholipid bilayer that provides support and regulates movement of substances into and out of the cell
Plant rough endoplasmic reticulum function
network of membranes throghout the cytoplasm lined with ribosomes. involves with synthesis of proteins
Plant nucleus function
the control center of the cell
Plant nucleolus function
serves to combine proteins and RNA to make ribosomal subunits
Plant nuclear membrane (envelope) function
membrane surrounding the nucleus. posesses numerous nuclear pores
Plant peroxisome function
vesicle containing enzymes that help in breaking down fatty acids and neutralizing hydrogen peroxide
Plant smooth endoplasmic reticulum function
main site of steroid, fatty acid and lipid synthesis. No ribosomes. Site of detoxification
Plant mitochondrian function
site of aerobic cellular respiration
Plant golgi complex function
recieves, packages, stores, and ships protein products. Produces lysosomes and other vesicles
Plant chloroplast function
site for photosynthesis
Plant vacuole function
large fluid filled sac that helps maintain the shape of the cell and stores metabolites
Parts of the cytoskeleton in an animal cell
actin filament, microtubule, intermediate filament
Animal cytoskeleton function
the cytoskeleton gives a cell its shape, offers support, and facilitates movement through three main components: actin filament, intermediate filament and microvilli
Animal centrosome parts
pericentriolar material, centrioles
Animal centrosome function
organelles responsible for the organization and nucleation of microtubules in animal cells and also regulate the cell cycle during cellular division
Animal plasma membrane function
protect the cell from its surroundings. Selective barrier
Animal lysosome function
organelles that contain digestive enzymes. They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria
Animal smooth ER function
synthesis of lipids, cholesterol and detoxification
Animal peroxisome function
break down long fatty acid chains through beta-oxidation
Animal mitochondria function
produce ATP (energy)
Animal microtubule function
They move vesicles, granules, organelles like mitochondria, and chromosomes via special attachment proteins
Parts of animal nucelus
Chromatin, nuclear envelope, nucleolus
Animal nucleus function
contains the cell’s genetic material
Animal chromatin function
efficiently package DNA into a small volume to fit into the nucleus of a cell and protect the DNA structure and sequence
Animal nuclear envelope function
surrounds and protects the Eukaryotic cell’s DNA (surrounds nucleus)
Animal nucleolus function
contains all of the information needed for DNA replication, flow of proteins and RNA, all while controlling the synthesis of protein and cell replication.
Animal glycogen granules function
the main storage form of energy is glycogen stored in the glycogen granules
Animal cytoplasm function
contains organelles and cell parts. gives the cell shape
What is cytosol?
part of the cytoplasm that does not contain organelles
Animal rough ER function
series of tubules that contains ribosomes that are responsible for the synthesis of proteins
Animal ribosome function
responsible for the synthesis of proteins
Animal golgi complex function
process and bundle macromolecules like proteins and lipids as they are synthesized within the cell.
Animal actin filament function
cytoskeletal fimament that helps the cytoskeleton to maintain and change their shapes as needed, to resist physical stresses, to transport vesicles through the cytosol, or to move around autonomously
Three postulates of cell theory
- all living things are composed of cells
- Cells are the basic unit of structure and function of all living things
- cells come only from pre-existing cells
Plant vs animal cell
chloroplast, cell wall, vacuoles
Enzyme
a biological catalyst that accelarates a reaction without itself being affected by the reaction
Metabolism
the sum total of chemical processes within an organism
Activation energy
the original input of energy necessary to initate a reaction
Substrate
the reacant that the enzyme reacts upon
Active site
portion of the enzyme that binds to the substrate
Catabolic
bodily processes that break down substances
Anabolic
bodily processes that build new substances
Cofactors
usually nonorganic metal ions that aid the action of an enzyme
Coenzymes
nonprotein organic molecules that improve enzymatic action
Inhibitors
bind to an enzyme to decrease its acitivy
Activators
bind to an enzyme to increase its activity
Catalase
enzyme produced by the liver that breaks down H2O2
Osmosis
the movement of water across plasma membranes in a living system
Diffusion
the random movement of molecules from regions of greater concentration to regions of lesser concentration
Selective permeability
allows certain molecules or ions to pass through it by means of active or passive transport
Equilibrium
with regards to diffusion, it is equal distribution of molecules within a system
Hypotonic
there is a lower concentration of solute relative to the inside of the cell
Hypertonic
there is a higher concertration of solute relative to the inside of the cell
Isotonic
a solution that contains the same concentration of solutes as the inside of the cell
Active transport
movement of molecules across a membrane against the concentration gradient. Requires the use of ATP and pumps in the membrane
Passive transport
Passage of substances through the membrane that does not require the use of ATP
Endocytosis
transport of large macromolecules into the cell
Exocytosis
transport of large macromolecules out of the cell
Denature
loss of function of an enzyme because its shape has been altered
Factors that affect enzymatic action
pH, temperature, optimal enzymatic ranges, denature
Independent and dependent variable in the pH enzyme experiment
Independent: pH
Dependent: Bromelain activity
Independent and dependent variable in the temperature enzyme experiment
Independent: temperature
Dependent: Bromelain activity
Why is optimal temperature/pH important for an enzyme
When outside optimal range, enzyme will not work properly. Different enzymes have different optimal temperatures
How does increasing and decreasing temperature affect the enzyme
Increasing temperature affects the enzyme much more dramatically. They denature much more rapidly at higher temperatures than lower
How does increasing and decreasing pH affect the enzyme
Increasing and decreasing the temperature denature the enzyme at the same rate. Have equal effect on enzyme activity
Celery stick experiment: explain results
- distilled and salt water
- distilled water moved into celery (hypotonic), celery became strong
- salt water drew water out of the celery. More water in celery stick so the water was drawn out. Celery stick became very flexible (hypertonic)
Elodea leaf experiment: explain results
- distilled water: moved into the cell. The cell expanded and the central vacuole grew and became very visible (hypotonic)
- salt water: water moved out of the cell. The cell shrunk and plasmalysis, or the separation of the cell membrane and cell wall, began to occur. (hypertonic)
What is the effect of temperature on rate of diffusion. How was this tested in the lab
Higher temperature increases rate of diffusion. This was tested by putting food coloring into various beakers with different temperatures and seeing how long it took to become a homogeneous solution. Boiling water diffused the food coloring almost instantaneously, while you could watch the exact path of the food coloring diffusing and it took a long time in the cold water
