Cell Bio Flashcards
Nucleolus
Subsection of nucleus where ribosomal RNA is synthesized
Lysosomes
Membrane bound structures
Contain hydrolylic enzymes that can break down different substrates and cell waste products
When these enzymes are released autolysis of the cell occurs which leads to apoptosis
Rough ER
Studded with ribosomes, that allow translation of proteins that are suppose to be secreted in lumen
Smooth ER
Does NOT have ribosomes
Used for lipid synthesis and for the detoxification of certain drugs and poison
transport proteins from the RER to the golgi apprantus
Golgi Apparantus
Materials modified, repackaged and transferred
Peroxisomes
Contain hydrogen peroxide
Break down long chains of fatty acids via Beta oxidation
Synthesis of phospholipids and enzymes for pentose phosphate pathway
Cytoskeleton
Structural support- stability and rigidity and transport pathways
Microfilaments, microtubules and intermediate filaments
Microfillaments
Solid rods of actin
Provide structural protection for cell and can cause muscle contraction through interactions with myosin.
They help form cleavage furrow during cytokinesis in mitosis
Microtubules
- Composed of tubulin
- Create pathways for motor proteins like kinesin and dynein to carry vesicles
- Contribute to the structure of cillia and flagella, where they are organized in a ring with two microtubules at the center (9+2 structure).
- Centrioles are found in centrosomes
2 organizing centers for microtubules
Centrosomes
Basal body
Intermediate fillaments
Involved in cell-celll adhesion or maintenance of integrity of the cytoskeleton
Help anchor organelles
Examples: keratin and desmin
Epithelial Tissues
- covers the body and line its cavities, protecting against pathogen invasion and desiccation. Some epithelial cells absorb or secrete substances or participate in sensation.
- Form Parenchyma
- Polarized
Parenchyma
Functional parts of the organ
Epithelial tissues form this
Layers in Epithelia
Simple Epithelia - one layer
Stratified Epithelia - many layers
Psuedostatified Epithelia - appear to have many layers because the differences in cell heights, but actually have one layer
Epithelia cell shape
Cuboidal cells- cube shaped
Columnar cells- long and narrow
Squamous cells- flat and scale like
Connective tissue
- Supports the body and provides framework for epithelial cells
- Stroma
Stroma
Support structure by secreting materials to form an extracellular matrix
Connective tissue
Examples of connective tissue
Bone, cartilage, tendons, ligaments, adipose tissue and blood
What group is prokaryotes part of
Archea and bacteria
Archea
Single celled
Extremophiles (living in harsh environment)
Chemosynthesis- can use alternate sources of energy
How are Archea similar to Eukaryotes and prokaryotes
Eukaryotes: Start translation with methionine, contain RNA polymerases and associate DNA with histones
Prokaryotes: Single circular chromosome and divide by binary fission
Bacteria
Contain cell membrane, cytoplasm and some have flagella
Bacteria Shape
Cocci- Spherical Shape
Bacilli- Rod-shaped
Spirilli- Spiral shaped
Gram-positive bacteria
Purple
-Thick cell wall of peptidoglycan and Lipoteichoic acid
Gram-Negative bacteria
Pink-red
- Thin cell wall composed of peptidoglycan an outer layer of phospholipids and lopopolysaccharides.
Cillia
Projection from the cell that allow movement of material along the cell surface such as in the respiratory tract
Flagella
Movement of the cell itself; sperm
9+2 structure
Cillia and flagella
9 microtubules in the outer ring and 2 microtubules in the center
Shapes of bacteria
Cocci- spherical shape
Bacilli- rod shaped
Spirilla- spiral shaped
Chemotaxis
The ability of a cell to detect chemical stimuli and move toward or away from them
Prokaryotic flagella made of
Makes up of filament, basal body and hook
Virulent factors
Traits that increase how pathogenic a bacteria is such as toxin production- can get through plasmids
Episomes
Subset of plasmids that are capable of integrating into the genome of the bacterium
Transformation
A form of recombination in bacteria
Genetic material from the environment can be integrated into bacterial genome
Conjugation
Sexual reproduction in bacteria
2 cells forming a conjugated bridge between them that allows for the transfer of genetic material. Unidirectional transfer from donor male to female
Transduction
The transfer of genetic material from one bacterium to another using bacteriophage as a vector (virus)
Teanspoons
Genetic elements that can insert into or remove themselves from the genome
Bacterial growth phases
Lag phase- bacteria adapt to new local conditions
Exponential- growth increases
Stationary - resources reduced and growth levels off
Death- as resources become insufficient
Viruses
No organelles or nucles
Composed of genetic material, protein coat and some have lipids
Capsid
Protein coat
Virons
Individual virus particles that can be resealed into host cell
Bacteriophages
Viruses that specifically target bacteria
Don’t enter only eject
They contain tail sheath which inject genetic material and tail fibers which allow it to attach to host cell
Retroviruses
Are enveloped single stranded RNA virus to which a complementary dna strand is synthesized using reverse transcriptase and then dna integrates into host dna
Eg- hiv
Lyric cycle
Makes massive number of virons until cell loses. Bacteria in this phase are called virulent
Lysogenic
The virus integrates into the host genome as a provirus or prophase and reproduces along with the cell. Then provirus leave the genome at some time in response to a stimuli and enter the lytic cycle
