biology Flashcards
- all living things are made up of cells
- the cell is the basic unit of life
- cells arise ONLY from preexisting cells
- cells carry genetic information (DNA)
what is cell theory?
_ is an aqueous component that allows molecules to diffuse throughout cell
cytosol
_ are not considered living because they: are acellular, require host cell for reproduction, and may contain RNA
viruses
eukaryotes have _ organelles
membrane-bound
DNA (in nucleus) is organized into _
chromosomes
phospholipids form _ interior-exterior and a _ core
hydroPHILIC; hydroPHOBIC
_ is a double membrane that contains nuclear pores
nuclear membrane (envelope)?
_ allow two-way material exchange between nucleus and cytosol
nuclear pores
_ are coding regions (DNA)
genes
rRNA (ribosomal RNA) is synthesized in the _
nucleolus
_ of mitochondria forms a barrier with cytosol
outer membrane
_ of mitochondria is folded into cristae
inner membrane
cristae contains enzymes for _
electron transport chain
_ is located inside inner mitochondrial membrane
mitochondrial matrix
mitochondria is able to independently divide via _
binary fission
_ can be triggered by mitochondrial enzymes being released into cytoplasm
apoptosis (cell death)
_ contain hydrolytic enzymes
lysosomes
_ break down substances from endocytosis and cellular waste
hydrolytic enzymes
_ (of cell) can occur when hydrolytic enzymes are relased
autolysis
a series of interconnected membranes that is continuous with nuclear envelope
what is the endoplasmic reticulum (ER)?
_ ER has ribosomes; _ ER lacks ribosomes
rough; smooth
_ allows protein translation
rough ER
_ is used for lipid synthesis and detoxification
smooth ER
location for modification, packaging, and transport of cellular products to specific locations
golgi apparatus
peroxisomes contain _
hydrogen peroxide
peroxisomes break down long chain fatty acids via _
Beta-oxidation
_ participate in phospholipid synthesis and pentose phosphate pathway
peroxisomes
the part of the cell that provides stability and rigidity; provides transport pathways
what is the cytoskeleton?
microfilaments contain the protein _
actin
_ provide structural protection
microfilaments
muscle contraction can result from interaction between microfilaments and _
myosin
microfilaments help form _ during cytokinesis stage of mitosis
cleavage furrow
microtubules are formed by the protein _
tubulin
microtubules create pathways for the motor proteins _ and _
kinesin, dynein
microtubules contribute to the _ structure of flagella and cilia
9+2
centrioles are found in _
centrosomes
centrioles are involved in _ organization
microtubule
_ filaments help anchor organelles
intermediate
_ maintain the integrity of the cytoskeleton (cell to cell adhesion)
intermediate filaments
tissues that line body cavities and cover the body
what are epithelial tissues?
_ protect body from pathogens and dessication
epithelial tissues
functional part(s) of organ
what is parenchyma?
the parenchyma is formed by _
epithelial cells
epithelial cells may be _, which means one side faces the lumen or outside while the other side faces vessels or structural cells
polarized
_ epithelia have one layer; _ epithelia have several layers
simple; stratified
_ epithelia look like they have multiple layers, but they only have one layer
pseudostratified
_ cells are shaped like cubes
cuboidal
_ cells are long and narrow
columnar
_ cells are flat and scale-like
squamous
tissues that support the body and provide a framework for epithelial cells
what is connective tissue?
connective tissue forms _ in most organs
stroma
_ support structure by secreting materials that form the extracellular matrix
connective tissue
_ include bones, cartilage, tendons, ligaments, adipose tissue, and blood
connective tissues
_ organize genetic material in a single (circular) model of DNA, so they do not have organelles
prokaryotes
this region contains the genetic information of prokaryptes
what is the nucleoid region?
in the domains of life, _ and _ are prokaryotic while _ is non-prokaryotic
archaea, bacteria; eukarya
archaea are _, which means they can live in harsh environments and can use alternate energy sources
extremophiles
bacteria have complex relationships with humans, which can include _ or _
symbiosis, pathogenesis
_ are spherical bacteria; _ are rod-like bacteria; and _ are spiral-shaped bacteria
cocci; bacilli; spirilli
_ (bacteria) need oxygen for metabolism
obligate aerobes
_ (bacteria) carry out anaerobic reproduction, cannot survive environments with oxygen
obligate anaerobes
_ (bacteria) can survive with or without oxygen; metabolism is adaptable to environment
facultative anareobes
_ (bacteria) can survive in environment with oxygen, but cannot USE oxygen for metabolism
aerotolerant anaerobes
cell wall and membrane together form the _
envelope
the structure that controls movement of solutes into and out of the cell
envelope
during gram staining, gram positive bacteria turn _ while gram negative bacteria turn _
purple; pink-red
gram positive bacteria have a _ cell wall; contains peptidoglycan and lipoteichoic acid
thick
gram negative bacteria have a _ cell wall; contains peptidoglycan, phospholipids, and lipopolysaccharides
thin
movement in response to a chemical stimuli
what is chemotaxis?
prokaryotes use _ for electron transport chain
cell membrane
prokaryotic ribosomes are _ than eukaryotic ribosomes
smaller
in _, the chromosome replicates while cell grows, then divides into 2 identical daughter cells
binary fission
“antibiotic resistance genes” in the plasmid
what are virulence factors?
_ are plasmids that can integrate into the genome
episomes
bacterial genetic recombination _ bacterial diversity
increases
the acquisition of genetic material from environment
what is transformation?
the transfer of genetic material from one bacterium to another via bridge
what is conjugation?
plasmid can be transferred from _ to _ cells
F+; F-
the transfer of genetic material from one bacterium to another using a vector
what is transduction?
genetic elements tha can insert or remove themselves from genome
what are transponons?
_ has 4 phases:
1. lag phase
2. exponential (log) phase
3. stationary phase
4. death phase
bacterial growth
bacteria adapt to local conditions
what is lag phase?
growth increases exponentially
what is log phase?
growth levels off since resources are reduced
what is stationary phase?
what occurs to bacteria when resources become insufficient?
death phase
protein coat
what is a capsid?
_ contain genetic material, capsid, and sometimes lipid-containing envelope
viruses
viruses cannot survive and replicate outside of a host cell, which makes them _
obligate intracellular parasites
individual virus particles
what are virions?
viruses that target bacteria
what are bacteriophages?
_ (bacteriophage) injects genetic material into bacterium
tail sheath
_ allow bacteriophage to attach to the host cell
tail fibers
viral genomes may be made of various _
nucleic acids
single-stranded RNA viruses than can be translated by host cell
what is positive sense?
single-stranded RNA viruses which require complementary strand to be synthesized with RNA replicase
negative sense
_ contain single-stranded RNA genome
retroviruses
_ creates a complementary DNA strand
reverse transcriptase
viruses attach to specific _ to infect cells
receptors
viral _ are released through cell death, lysis, or extrusion
progeny
bacteriophage produces many new virions until cell lyses
what is the lytic cycle?
bacteria in lytic phase are called _
virulent
virus integrates into host genome, which then reproduces along with cell
what is the lysogenic cycle?
infectious proteins; trigger misfolding of other proteins
what are prions?
prions _ solubility and degradability of misfolded protein
decrease
small circles of DNA that can turn off genes (can result in cell death)
what are viroids?
viroids are mostly considered _ pathogens
plant
