Cell Biology Flashcards
Where are ribosomes synthesized?
Nucleolus
True or False: Mitochondria replication is synched with the cell cycle
False
How do mitochondria replicate?
Binary Fission
Where are proteins synthesized from free floating ribosomes destined?
Free floating ribosomes make proteins destined for intracellular destinations
Where are proteins synthesized from ribosomes bound to ER destined?
Extracellularly
Products being received by the golgi are received at what face?
Cis
Products exported by golgi exit at what face?
trans
What is a major difference in the generation of lysosomes versus peroxisomes?
Lysosomes are formed by pinching off as vesicles from the Golgi apparatus, but this is not true of peroxisomes.
Why don’t hydrolytic enzymes within the lysosome function well outside of the lysosome?
The internal pH of the lysosome is about 4.5 which is optimal for the enzymes. If the lysosome were to burst, the neutral pH of the cytosol would not be optimal for enzyme function
What is the major function of peroxisomes?
detoxification of reactive oxygen species
What is the major function of lysosomes?
autophagy of cell garbage
What are the three major components of the cytoskeleton?
Microfilaments, intermediate filaments, microtubules
Describe the structure of microfilaments
-Made of double helices of actin -globular actin (g-actin) is stringed together to form filaments (f-actin)
What purpose do microfilaments serve?
They are important for: -Phagocytosis -cleavage furrow -muscle contraction
What modifications to products can occur in the golgi apparatus?
adding groups of carbs, phosphates, and sulfates
What is an important function of peroxisomes?
Hydrogen peroxide is found in peroxisomes and is important for breaking down long chain fatty acids during B-ox
Where is rRNA synthesized?
nucleolus
What does extranuclear inheritance?
Mitochondria
True or False: Mitochondrion can release enzymes that start apoptosis
True
This part of the cytoskeleton is make of keratin, desmin, vimetin, and lamins
Intermediate filaments
Cilia and Flagella are made of _______________
Microtubules
What is the purpose of microtubules on the inside of the cell?
They are a platform for kinesins and dyenins to transport vesicles
Where is the positive and negative ends of the cell?
Positive is towards the outside and negative towards the inside
What are the purpose of microtubles on the outside of eukaryotic cells?
Cilia and flagella for movement
What part of the cytoskeleton is resistant to compression?
Microfilaments
What is the main function of the nucleolus?
ribosomal rna/ ribosome synthesis
What is the difference in structure between centrioles and flagella/cilia?
Centrioles are hollow with 9 triplets of tubulin while flagella and cilia have the 9+2 structure.

What structure do centrioles have?
Triplicate microtubles assembled into hollow tube

True or False: Hemidesmosomes are involved with cell to cell adhesion
False- they connect to the extracellular matrix
Desmosomes are anchored to keratin. Whcih cytoskeletal structure would this include?
Intermediate filaments
What does the nucleolus do?
Produces ribosomes in eukaryotes (essentially)
True or False: Bacteria can confer antibiotic resistance between two different bacteria species through conjugation
True
What forms of genetic material can viruses use?
SIngle or double stranded DNA or RNA
What are the two classes of single stranded RNA?
Positive and negative sense viruses
What is the difference between a positive and negative sense RNA virus?
Positve sense virus: its RNA is already oriented to be translated
Negative sense viruses can be thought of as complementary to mRNA and need RNA REPLICASE to transcribe the correct transcript
What is the difference between RNA Replicase and Reverse Transcriptase?
RNA Replicase is carried by viruses that have Negative Sense RNA. Reverse Transcriptase is used by retroviruses to synthesize DNA from RNA. This DNA is then incorporated into the host cell.
What is the process of extrusion?
Extrusion is very similar to exocytosis. It is when virions are released fromt he host cell in a manner that does not damage the host cell, or they can also be produced in such quantities that they cause host cell lysis.
Peptidoglycan
Structural carb that makes up bacterial cell walls
Gram Positive vs Gram Negative
Gram positive: turns purple in gram stain due to thick peptidoglycan wall
Gram Negative: turns pink in gram staining, they have a thin wall with outer lipopolysaccharide layer
True or False: The lytic cycle only occurs for bacteriophages
true
What intercellular connection between endothelial cells of brain capillaries result in the blood brain barrier?
Tight Junctions
Desmosomes
Intercellular junctions that function as anchors to form strong sheets of cells
Gap Junctions
Intercellular Junctions that provide cytoplasmic channels between adjacent cells
Intercalated Discs
Special intercellular junctions between cardiac cells that provide direct electrical coupling
Made from connexins
Gap Junctions
Junctions that make up epitheleal tissue
Tight Junctions
Junction that prevents paracellular leakage
Tight Junction
Junction that helps anchor the cytoskeleton
Desmosomes