The Cell Flashcards
cell theory
- all living things are composed of cells
- the cell is the basic functional unit of life
- cells arise only from cells
- cells carry genetic information in the form of DNA that is passed onto daughter cells
eukaryotic cell
contain true nucleus
prokaryotic cell
do not contain a nucleus
cytosol
allows for diffusion of molecules throughout cell
nucleus
contains genetic material
deoxyribonucleic acid (DNA)
genetic material, organized into chromosomes
mitosis
replication of eukaryotic cells
nuclear membrane/envelope
double membrane that maintains a nuclear environment separate and distinct from cytoplasm
nuclear pores
allow selective two-way exchange of material
genes
coding regions of DNA
histones
organizing proteins around which DNA is wound
chromosomes
linear strands of DNA
nucleolus
subsection of nucleus where ribosomal RNA is synthesized
mitochondria
are the power house of the cell
outer membrane of mitochondria
serves as barrier
cristae
numerous foldings in the inner membrane of mitochondrion
inter-membrane space
space between inner and outer mitochondrial membranes
mitochondrial matrix
space inside inner membrane
cytoplasmic (extranuclear) inheritance
transmission of genetic material independent of the nucleus (ex. mitochondria)
apoptosis
programmed cell death; kick-started by release of enzymes from mitochondria
lysosomes
membrane-bound structures containing hydrolytic enzymes capable of breaking down many different substrates
endosomes
transport, package and sort cell material traveling to and from the membrane
autolysis
release of enzymes from lysosomes that trigger apoptosis
endoplasmic reticulum (ER)
series of interconnected membranes continuous with nuclear envelope
rough ER
studded with ribosomes
smooth ER
utilized for lipid synthesis and detoxification
golgi apparatus
consists of stacked membrane-bound sacs; functions to modify and transport cellular products
exocytosis
secretory vesicle merges with the cell membrane and its contents are released outside
peroxisomes
contain hydrogen peroxide; breakdown of chain fatty acids through beta oxidation
cytoskeleton
provides structure and shape to cell
microfilaments
made up of actin filaments
actin filaments
resistant to compression and fracture; provide protection
actin and myosin
work together to contract muscle
cleavage furrow
formed from microfilaments; separates two new daughter cells
microtubules
made up of tubulin; radiate throughout cell providing primary pathway for motor proteins
cilia
made of microtubules; help to move materials along surface of cell
flagella
also made of microtubules; involved in movement of cell itself
9+2 structure
structure of eukaryotic flagella and cilia; 9 doublets with 2 microtubules
centrioles
organizing centers for microtubules found in the centrosome; organize mitotic spindle
kinetechores
complexes on chromosomes to which centrioles attach
intermediate filaments
diverse group of filamentous proteins; keratin, destine, vementin and laming; involved in cell-cell adhesion or maintenance of the cytoskeleton; anchor organelles
epithelial tissues
cover body and line its cavities
basement membrane of epithelial tissue
bind cells together tightly to maintain a cohesive unit
parenchyma
functional parts of the organ
simple epithelia
one layer of cells
stratified epithelia
multiple layers of cells
pseudostratified epithelia
only one layer of cells but appears to have multiple because of differences in cell height
cuboidal
cube-shaped cells
columnar
long and thin cells
squamous
flat, scale-like cells
connective tissue
supports body and organs
stroma
supportive structures for organs
extracellular matrix
collagen and elastin
nucleoid region
area of a prokaryotic cell in which DNA is concentrated
archaea
single-celled organisms visually similar to bacteria but functionally similar to eukaryotes
extremophiles
coming found in harsh environments
mutualistic symbiotes
both host and bacteria benefit
pathogens/parasites
do not benefit host, cause disease
cocci
spherical bacteria
bacilli
rod-shaped bacteria
spirilli
spiral-shaped bacteria
obligate aerobes
need O2 for metabolism
obligate anaerobes
can not survive in environments with O2
facultative anaerobes
can use O2 for metabolism or can use other mechanisms in non-O2 environments
aerotolerant anaerobes
unable to use O2 for metabolism but are not harmed by its presence
cell wall
outer barrier of prokaryotic cell
cell envelope
cell membrane + cell wall
gram positive cell wall
cell envelope absorbs crystal violet stain, appears purple; consist of a thick layer of peptidoglycan and lipoteichoic acid
gram negative cell wall
cell envelope absorbs safranin counterstain, appears red; contain small amounts of peptidoglycan; contains outermembranes with lipopolysaccharides that cause inflammatory response in humans
chemotaxis
ability of a cell to detect a chemical and move toward/away from it
flagella filament
hollow, helical structure composed of flagellin
flagella basal body
complex structure that anchors flagellum to membrane; also serves as motor
flagella hook
connects the filament and the basal body
plasmid
extrachromosomal DNA that is not necessary for survival
binary fission
simple form of asexual reproduction seen in prokaryotes
virulence factors
traits that increase how pathogenic a bacterium is
episomes
subset of plasmids capable of integrating into the genome of a bacterium
transformation
integration of foreign genetic material into the host genome
conjugation
bacterial form of mating; unidirectional from donor male (+) to recipient female (-)
conjugation bridge + sex pili
sex pili make a bridge to facilitate conjugation between two cells
sex factors
contain genes necessary for conjugation; F (fertility) factor is one of these
Hfr (high frequency of recombination)
cells that have had the F factor integrated into their host genome
transduction
genetic recombination that requires a vector
vector
virus that carries genetic material from one bacterium to another
bacteriophages
viruses that infect bacteria
transposons
genetic elements capable of inserting and removing themselves from the host genome
growth of a bacteria
- lag phase
- exponential(log) phase
- stationary phase
- death phase
capsid
protein coat of a virus
virions
viral progeny that are released to infect additional cells
virus tail sheath
acts like a syringe to insert genetic material into a bacterium
virus tail fibers
help bacteriophage to recognize and connect to correct host cell
positive sense RNA virus
genome may be directly translated to functional proteins by ribosomes of host cell
negative-sense RNA virus
require synthesis of an RNA strand complementary to their strand, which can then be used as a template by the host cells
RNA replicase
carried by negative-sense RNA viruses to synthesize a complementary strand
retrovirus
single-stranded RNA viruses that can synthesize DNA to be directly put into host genome; can lie dormant indefinitely and the only way to kill their DNA is to kill the host
reverse transcriptase
used by retroviruses to synthesize their DNA
extrusion
process by which viral progeny leaves a cell and takes part of the host plasma membrane
lytic cycle
bacteriophage use max use of the cell’s machinery; eventually host cell lyses and virions attack new cells; virulent
lysogenic cycle
virus enters the host genome as a provirus or prophage; certain environmental factors will prompt the provirus to leave the genome and return to the lytic cycle at some point
prions
infectious proteins; cause disease by triggering misfolding of other proteins
viriods
small pathogens consisting of very short circular RNA that infects plants; silence genes in plant genome
