Biology Flashcards
4 fundamental tenets of cell theory
- All living things are composed of cells
- All cells arise from preexisting cells
- Cells are the basic unit of life
- All cells contain DNA, which is passed from parent to daughter cell
where is rRNA synthesized?
nucleolus
where does the electron transport chain occur?
mitochondrial inner membrane
cytoplasmic/extranuclear inheritance
transmission of genetic material independent of the nucleus
endosomes
organelles that transport, package, and sort cell material traveling to and from the cell membrane
what does the rough ER do?
synthesize proteins destined for secretion
what does the smooth ER do?
synthesize lipids for secretion or for the cell membrane and detoxify certain drugs and poisons
proteins synthesized in the cytoplasm are destined for where?
to remain within the cell
peroxisomes
contain hydrogen peroxide for the degradation of long chain fatty acids by B oxidation, aid in the synthesis of phospholipids, and contain some of the enzymes needed for the HMP shunt
microfilaments
component of the cytoskeleton which is made of actin; provide protection for the cell and initiate the formation of the cleavage furrow during cytokinesis
microtubules
component of the cytoskeleton which is made of tubulin
which main component of the cytoskeleton do kinesin and dynein primarily ride along?
microtubules
flagella and cilia are examples of what kind of cytoskeleton component?
microtubules
how are cilia and flagella organized in eukaryotes?
9+2 structure; 9 pairs of microtubules arranged in a circle surrounding 2 microtubules in the center
which component of the cytoskeleton is involved during mitosis?
microtubules; microtubules originating from the centrioles attach to chromosomes at their kinetochores and pull the sister chromatids apart
intermediate filaments
component of the cytoskeleton which is made of keratin, desmin, vimentin, and lamins; involved in cell-cell adhesions, anchoring other organelles, and maintaining the cytoskeleton’s integrity
4 types of tissue
epithelial, connective, muscle, nervous
epithelial tissue
cover the body and line the cavities; anchored to a basement membrane; typically one side of the tissue is open to a lumen (outside world) and the other to blood vessels or other cells (inside world)
what type of tissue contributes to the parenchyma (functional parts) of an organ
epithelial tissue
examples of connective tissue
bone, cartilage, tendons, ligaments, adipose tissue, blood
connective tissue
supports the body and provides a framework for epithelial cells; contribute to the structure of the body
structure of centrioles in eukaryotes?
9 triplets of microtubules arranged in a circle with a hollow center
spherical bacteria
cocci
rod-shaped bacteria
bacilli
spiral-shaped bacteria
spirilli
obligate aerobe
bacteria requiring oxygen for metabolism
obligate anaerobe
bacteria that cannot survive in environments with oxygen
facultative anaerobes
bacteria that can use oxygen for metabolism or other means for metabolism
aerotolerant anaerobes
bacteria that cannot use oxygen for metabolism but that are not harmed by being in an environment with oxygen
which are more resistant to antibiotics - gram negative or gram positive bacteria?
gram negative
which type of bacteria have thicker cell walls with peptidoglycan?
gram positive
what color do gram positive bacteria stain?
purple
what color do gram negative bacteria stain?
pink/red
chemotaxis
ability of a cell to detect chemical stimuli and move toward or away from them
structure of prokaryotic flagella
basal body attaches the flagella to the cytoplasm and rotates like a motor, causing the hook to exert torque on the filament, which then causes the filament to spin and propel the prokaryote forward
what is the structure of prokaryotic DNA?
circular
plasmids
circular structures in prokaryotes containing DNA acquired from external sources that are not necessary for the survival of the prokaryote, but may confer certain advantages such as antibiotic resistance
how are Archaea similar to Eukarya?
both start translation with methionine, have their DNA associated with histones, and share similar RNA polymerases
3 types of genetic recombination in prokaryotes
transformation, conjugation, transduction
transformation
integration of foreign genetic material into the host genome; typically occurs when other bacteria lyse and spill their contents into the vicinity of a bacterium capable of transofrmation
conjugation
bacterial form of mating/sexual reproduction where the male bacteria containing a sex factor forms a pili bridge to the female bacteria, connecting them; the male bacteria with the sex factor copies its sex factor and that copy makes it way across the pili bridge into the female bacteria, who now also has a sex factor; the female bacteria with the sex factor now can be viewed as a male bacteria and donate its sex factor to a female bacteria by way of making a pili bridge; this is significant because sex factors could contain info on antibiotic resistance and by passing by conjugation, this information could be added to every bacteria within a bacterial colony very quickly
transduction
occurs when a bacteriophage infecting a bacteria picks up some of that bacteria’s genetic material and transfers it to another bacteria when infecting it with its own virulent information
transposons
genetic elements capable of inserting and removing themselves from the genome; seen in both prokaryotes and eukaryotes and can disturb genes if inserted/removed from a coding region
stages in a bacterial colony’s life cycle
lag phase, exponential phase, stationary phase, death phase
positive sense viruses
virus containing RNA; once inside the host cell, the RNA can be translated by host cell ribosomes
negative sense viruses
virus containing RNA; once inside the host cell, the virus uses its RNA replicase enzyme to convert the RNA strand into one that can be read and translated by host cell ribosomes
retroviruses
virus containing RNA; once inside the host cell, the virus uses its reverse transcriptase enzyme to convert the RNA strand into DNA so it can be incorporated into the host cell’s DNA
lytic cycle
stage of the viral life cycle where the bacteriophage maximizes the use of the cell’s machinery with little regard for the survival of the host cell; eventually the cell lyses when full of copies of the virus
lysogenic cycle
stage of the viral life cycle where the viral genetic material integrates into the host genome as a prophage and is replicated as the cell replicates its DNA; the virus can leave the lysogenic cycle and enter the lytic cycle when exposed to certain environmental factors
prions
infectious proteins that lead to the misfolding of other proteins (normally an a helix is converted to a B pleated sheet) so that protein aggregates form that cannot be dissolved
viroids
small pathogens consisting of a very short, circular, single-stranded RNA that infect plants
episomes
plasmids that can incorporate into the bacteria’s genome
what types of nucleic acid could form the genome of a virus?
single-stranded RNA, double-stranded RNA, single-stranded DNA, or double-stranded DNA
