Lab 1-3 Exam Flashcards
Key points for setting up a microscope.
- start on low power
- center and focus
- set the condenser
- move un to high power, remember to center and focus
- adjust iris diaphragm
What is the formula for estimating the actual size of a cell/organism?
diameter of field of view/ # of times the cell/organism fits across the field of view
What is the diameter of field of view for the 4x, 10x, and 40x objective lens?
4.40mm, 1.75mm, 0.44mm
What four basic structural features do all living cells have?
- plasma membrane
- cytoplasm
- DNA
- ribosomes
Define prokaryotes
cell or organism that lacks membrane-bound organelles and a true nucleus
Define glycocalyx
it traps water and protects the bacterium from desiccation
Define capsule
a very thick glycocalyx in bacterial cells which prevent the bacteria from being destroyed by an animal’s immune system or to help them adhere to surfaces
Define nucleoid
region of prokaryotes where genetic material is located (usually one circular chromosome)
Define eukaryotes
cell or organism that contains membrane-bound organelles and a true nucleus
Eukaryotic cells are ______ in size than prokaryotic cells.
larger
Chromosomes in eukaryotes are….
linear
Cell wall material in prokaryotes
polysaccharides and amino acids
Cell wall material in plants and fungi
cellulose or chitin respectively
What factors may contribute to pollution in the samples?
- climate
- sewage
- pesticide
- run-off
Examples of Light Microscopy
Fluorescence Microscopy
Confocal Laser Scanning Microscopy
Examples of Electron Microscopy
Transmission Electron Microscopy
Scanning Electron Microscopy
Prokaryotes include what groups of organisms?
bacteria and archaea
Eukaryotes include what groups of organisms?
plants, fungi, animals, and protists
Define plasmids
small pieces of circular DNA
What are the three types of plastids?
chloroplasts, chromoplasts, and leucoplasts
Green pigments that capture light energy used in photosynthesis called ________ are located on the _____________ in chloroplasts.
- chlorophyll
- thylakoid membranes
Define plasmodesmata
slender cytoplasmic connections used by plant cells to communicate
Define stomata
where gas exchange occurs
Define guard cells
regulate the opening and closing of stomata
Define anthocyanins
blue, purple, and red pigments that occur in the central vacuole some plants and are water soluble
Define pseudopodia
cellular extensions that form, enabling the organism crawl and perform phagocytosis
What cytoskeletal component is responsible for pseudopod formation?
microfilaments
Define phagocytosis
a process where pseudopodia encircles and traps small animals and other food particles to be packaged into food vacuoles
Define contractile vacuole
functions in osmoregulation
Define osmoregulation
maintenance of a constant internal solute concentration by an organism
What cytoskeletal component are cilia and flagella made of?
microtubules
Define cell wall
provides support and protection
Define central vacuole
- stores water, enzymes, ions, proteins, pigments, toxins
- provides support through maintenance of turgor pressure
Define chloroplasts
- where photosynthesis occurs
- contains chlorophyll
Define chromoplasts
-plastids that contain pigment (carotenoids) that give colouration to attract for pollination and seed dispersal
Define cilia
-short appendages that facilitate locomotion
Define cytoplasm
-creates an environment for processes that take place in the cell
Define cytoskeleton
gives cell shape and structure
Define microtubules
structure and movement of cilia + flagella, cell organization and shape
Define microfilaments
cell strength, shape + structure
Define flagella
long appendages used for locomotion
Define food vacuole
contains food particles engulfed by cell
Define golgi apparatus
modifies, stores, and ship products of the ER
Define leucoplasts
-plastid that lacks pigments; stores + produce different macromolecules
Define lysosome
-contains hydrolytic enzymes that digest a cells food + wastes
Define mitochondria
carries out cellular respiration and supplies majority of ATP
Define nucleolus
where ribosome subunit assembly occurs
Define nucleus
contains the cells genetic material and controls cells function, DNA synthesis, and RNA transcription
Define plasma membrane
separates a cell’s contents from surrounding environment and regulates passage of substance in and out of cell; selectively permeable
Define ribosomes
found in cytoplasm and synthesizes protein
Define rough ER
initial synthesis + sorting proteins for export; studded with ribosomes
Define smooth ER
lipid synthesis + modifications; detoxification of drugs and alcohol, calcium storage, glycogen breakdown
Define vesicles
contains macromolecules for storage, transport, or secretion
Define solute
a substance that is dissolved in a liquid
Define solvent
a liquid that has dissolved or can dissolve
Define solution
a liquid and its dissolved solutes
Define passive transport
transport occurs without the expenditure of energy (diffusion and osmosis)
Define diffusion
the random movement of molecules of a substance from an area of high concentration of that substance to an area of low concentration of that substance.
Define osmosis
the movement of a solvent (usually water) through a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration
Define isotonic
solute concentrations are same inside and outside of cell; therefore, equal movement of water in and out
Define hypertonic
if a cell has a higher solute concentration than their environment
Define hypotonic
cells have a lower solute concentration than their environment
Define turgor pressure
the plasma membrane forced to push outward
Define plasmolysis
contraction of a plant cell as a result of loss of water
Define binary fission
prokaryotic cell division (circular chromosome replicates, cell wall and cell membrane grow inward to divide into two, identical daughter cells)
Define chromatin
DNA and associated proteins
Define genes
specific nucleotide sequences of DNA that code for particular characteristics
Define mitosis
division of the nucleus, resulting in two genetically identical daughter nuclei
Define cytokinesis
division of cytoplasm between resulting daughter cells
What are some of the major functions of mitosis?
-production and maintenance of multicellularity
(development from zygote, to embryo, to adult)
-asexual reproduction
-replacement or old/damaged tissue
Describe Interphase
G1: cell growth, organelles form
S: DNA replicates
G2: resumes growth
Describe prophase
-chromosomes condense, nuclear envelope disintegrates , spindle microtubules begin to form
Describe metaphase
- spindle apparatus is fully formed
- microtubules attach to centromeres of chromosome which have
- lined up an mid point of the spindle
Describe Anaphase
- centromeres of each replicated chromosome separate and
- single chromosomes are pulled to opposite poles
Define telophase in plant cells
- single chromosomes at poles begin to uncoil,
- nuclear envelope forms around each group of chromosomes
- cytokinesis begins and cell plate forms and grows outward until it forms a complete cell wall that separates the two daughter cells
Define telophase in animal cells
- single chromosomes at poles uncoil
- nuclear envelope begins to form around each group
- cytokinesis begins and cleavage furrow forms between the 2 nuclei and pinches the cell into 2 separate daughter cells
Define multicellular
single organisms that have specialized cells that perform different functions
Define pyrenoid
contained within the chloroplast and is responsible for the synthesis of starch from the sugars produced by photosynthesis
Define colony
composed of individual cells or organisms that adhere to each other and may communicate with each other
