BIO Ch. 1 The Cell Flashcards
What is the role of the cytosol?
it allows for the diffusion of molecules throughout the cell
What is the role of the nuclear envelope?
separates the nucleus from the cytoplasm
What is the role of the nuclear pore?
allows for selective 2-way exchange of material b/w the cytoplasm and nucleus
What is the role of the mitochondrial membranes?
outer - serves as a barrier b/w the cytosol and the inner environment of the mitochondrion
inner - folded into cristae that increase the surface area for the ETC
intermembrane/matrix - pumps protons that flow through ATP synthase to establish the proton motive force
What is the role of the nucleolus?
It is where ribosomal RNA is synthesized
What is cytoplasmic or extranuclear inheritance?
the transmission of genetic material independent of the nucleus.
ex: the mitochondria have it’s genes and replicate independently of the nucleus via binary fission
What is the role of the lysosomes?
contains hydrolytic enzymes that can break down cellular waste products and substances ingested by endocytosis
What is the role of the endosomes?
transport, package, and sort cellular material traveling to and from the membrane, trans-golgi, or the lysosomal pathway for degradation
What is the role of the RER?
studded with ribosomes, which permit the translation of proteins destined for secretion directly into its lumen
What is the role of the SER?
utilized primarily for lipid synthesis, and drug detoxification, and can transport proteins from the RER to the Golgi apparatus
What is the role of the peroxisomes?
contains hydrogen peroxide that breaks down very long FA chains via b-oxidation, participates in the synthesis of phospholipids, and contains some of the enzymes involved in the PPP
What is the role of the cytoskeleton?
provides stability, rigidity, and cell structure, and helps the cell maintain its shape. made up of microfilaments, microtubules, and intermediate filaments
What is the role of the microfilaments?
helps to form cleavage furrows during cytokinesis In mitosis
What is microfilament made of?
made up of solid polymerized rods of actin
What is the role of actin?
actin filaments are organized into bundles and networks and are resistant to compression and fracture, protecting the cell. Actin also interacts with myosin to generate muscle contraction
What are microtubules made of?
hollow polymers of tubulin proteins
What is the diff b/w cilia and flagella?
cilia moves materials along the surface of the cell, while flagella is involved in the movement of the cell itself
What is the structure of cilia and flagella?
9 pairs of microtubules form an outer ring with 2 microtubules In the center (9 + 2 structure)
What is the role of centrioles?
organized centers of microtubules and are structures as 9 triples of microtubules with a hollow center
What is the role of intermediate filaments?
involved in cell-to-cell adhesions or maintain the overall integrity of the cytoskeleton, and they help to anchor other organelles like the nucleus
What is the difference in the layers of epithelial?
simple - have 1 layer
stratified - have multiple layers
pseudostratified - appears to have multiple layers due to differences in cells but in reality, are one 1 layer
What are the different shapes of epithelial?
cubodal - cube shapes
columnar - long and thin
squamous - flat and scalelike
What is the role of connective tissue?
support the body, provide a framework for epithelial cells to carry out their functions
What is the diff in the contribution of epithelia vs. connective tissue?
epithelial cells contribute to the parenchyma (functional part) of an organ, connective tissue is the main contributor to the stroma or support structure by secreting materials to form an extracellular matrix
What are examples of intermediate filaments?
filamentous proteins such as keratin, desmin, vimentin, and lamins
What are examples of cells that are composed of epithelial cells?
nephrons in the kidney, hepatocytes in the liver, acid-producing cells of the stomach, endothelial cells, a-cells
What are examples of connective tissue?
bone, cartilage, tendons, ligaments, adipose tissue, blood
What are the different shapes of bacterial cells?
spherical = cocci
rod = bacilli
spiral = spirilla
What is the role of the Golgi apparatus?
consist of stacked membrane-bound sacs in which cellular products can be modified, packaged, and directed to specific cellular locations
What are the 4 classifications of bacteria?
obligated aerobes, obligated anaerobes, facultative anaerobes, aerotolerant anaerobes
What is an obligate aerobe?
require oxygen for metabolism
What is an obligate anaerobe?
cannot survive in oxygen-containing environments, and can only carry out anaerobic metabolism
What is a facilitated anaerobe?
can survive with or w/o oxygen and will be used either for metabolism
What is an aerotolerant anaerobe?
cannot use oxygen for metabolism, but can survive in oxygen-containing environments
What is the diff in straining b/w gram-negative and positive?
gram-positive bacteria turn purple, while gram-negative bacteria turn pink-red
What is the diff b/w gram-negative and positive?
Gram-positive bacteria have a thick cell wall composed of peptidoglycans and lipoteichoic acid
gram-negative bacteria have a thin cell wall composed of peptidoglycan and an outer membrane containing phospholipids and lipopolysaccharide
What is the diff b/w eukaryotic and prokaryotic ribosomes?
prokaryotic ribosome - 30S and 50S
eukaryotic - 40S and 60S
What is transformation?
the acquisition of genetic material from the environment, which can be integrated into the bacterial genome
What is conjugation?
the transfer of genetic material from one bacterium to another across a conjugated bridge
What is transduction?
the transfer of genetic material from one bacterium to another using bacteriophage as a vector
What are transposons?
genetic elements that can inset into or remove themselves from the genome
What are the bacterial growth phases?
lag - bacteria get used to the environment; little growth during this time
exponential - bacteria are available resources to multiply at an exponential rate
Stationary-bacterial multiplication ceases as resources are used up
death - bacteria die when resources are insufficient to support the colony
What is a bacteriophage?
viruses that target bacteria
How does a virus infect cells?
by attaching to specific receptors, and then either fusing with the plasma membrane, being brought in by endocytosis, or injecting their genome into the cell
What are the 2 life cycles of bacteriophage?
lytic - the bacteriophage produces massive numbers of new virions until the cell lyses.
lysogenic - virus integrates into the host genomes as a provirus or prophage, which can then reproduce along with the cell, and enter the lytic phase at a later time
What are prions?
infectious proteins that trigger the misfolding of other proteins are usually converted from an a-helical structure to a b-pleated sheet, which decreases the solubility and degradability of the misfolding protein
What are virons?
plant pathogens that are small circles of complementary RNA that can turn off genes, resulting in metabolic and structural derangements of the cell and potential cell death
