Biology Ch. 1 Flashcards
List the core tenants of cell theory
1) All living things are composed of cells
2) The cell is the basic functional unit of life
3) Cells only arise from pre-existing cells
4) Cells carry genetic info in the form of DNA
Why aren’t viruses alive? List 2 reasons
1) Can’t reproduce
2) Contain RNA instead of DNA as genetic info
What is the coding region of DNA?
Genes
What is linear DNA wound around?
Histones
RNA is synthesized in the ______
Nucleolus
Describe the basic functions of the cristae of the mitochondria
Contains the molecules and enzymes of the electron transport chain and increases the surface area for the enzymes of the electron transport chain
The space between the cristae (inner membrane) and outer membrane of the mitochondria is _______
The intermembrane space
Describe how and why the mitochondria is semi-autonomous? How does it replicate?
The mitochondria contains some genetic information independent of the cell and replicates independent of the nucleus via binary fission
Define cytoplasmic/extranuclear inheritance? What organelle undergoes this?
The transmission of genetic material independent of nucleus, undergone by the mitochondria and chloroplasts, or during viral or bacterial infiltration
How do lysosomes work with endosomes?
Endosomes transport, package, sort cell material to and from membrane.
Lysosomes usually sequester toxic enzymes brought by endosomes to be degraded, but can release them for apoptosis
Define the serial endosymbiosis theory
Membrane bound organelles formed by engulfing of one prokaryote by another
List the double membrane bound organelles
1) Mitochondria
2) Nucleus
3) Chloroplast
4) Endoplasmic reticulum
5) Golgi Apparatus
Describe the function and structure of the Rough ER
Lined with ribosomes; permit translation of proteins to be secreted in lumen
Describe the structure and function of the Smooth ER
Lacking ribosomes; involved in lipid synthesis and detoxification and transports proteins from RER to Golgi Apparatus
Briefly describe the function(s) of the endoplasmic reticulum
Involved in protein and lipid syntheses, carbohydrate metabolism, drug detoxification, and intracellular transport
Briefly describe the function(s) of the Golgi Apparatus
Process and package proteins and lipid molecules, especially proteins destined to be exported from the cell.
Describe the functions and features of peroxisomes
Breakdown fatty acid chains via beta-oxidation and participate in the synthesis of phospholipids using hydrogen peroxide and enzymes involved in the pentose phosphate pathway
List the three elements of the cytoskeleton
1) microfilaments
2) microtubules
3) intermediate filaments
Microfilaments are made up of ___
Actin rods
List the functions and mechanisms of actin rods
1) Use ATP and interactions with myosin to generate movement
2) Contraction of actin filaments forms cleavage furrow
Describe the structure of cilia and flagella
9+2 structure: 9 pairs of microtubules form the outer ring, 2 center microtubules form the inner ring
Centrioles organize ___ during cell division
microtubules
List the intermediate filaments
1) Keratin
2) Desmin
3) Vitamin
4) Lamins
Describe the function(s) of intermediate filaments
Cell-cell adhesion, maintain cytoskeleton integrity, increase structural rigidity of cell, anchor organelles
List the 4 tissue types
1) epithelial
2) connective
3) muscle
4) nervous
Describe the function of epithelial tissue
Covers body and lines cavities to prevent against pathogen invasion. Also involved in absorption, secretion, and sensation
___ constitutes the parenchyma
Epithelial tissue
Nephrons, hepatocytes, and acid producing cells of the stomach are examples of ___ tissue
Epithelial
Epithelial cells are: a) polarized or b) unpolarized
A
Describe the function of connective tissue
Contribute to stroma, provides framework for epithelial cells, produce and secrete collagen or elastin to form extracellular matrix
Name the 2 components that form the extracellular matrix
1) collagen
2) elastin
Collagen and elastin are secreted by ___ tissue
Connective
Cartilage, bone, tendons, ligaments, adipose tissue, and blood are all examples of ____ tissue
Connective
List the 2 prokaryotic domains
1) archaea
2) bacteria
How is archaea similar to eukarya?
Contains genes, metabolic pathways, and histones
Prokaryotes divide via _____
Binary fission
List the 3 classification of bacteria
1) spirilli
2) cocci
3) bacilli
Define obligate aerobes
Bacteria that need oxygen to metabolize
Define obligate anaerobes
Bacteria that produce radicals and die in oxygen
Define facultative anaerobes
Bacteria that can use oxygen for aerobic metabolism or use anaerobic metabolism of oxygen is not present
Define aerotolerant anaerobes
Bacteria that doesn’t use oxygen to metabolize but won’t die in oxygen
List the 2 types of bacterial cell walls and their features
1) gram positive: stain purple, contain high amounts of peptidoglycan and lipoteichoic acid
2) gram negative: stain pink, contain low amounts of peptidoglycan
Gram negative bacteria have outer membranes made of ___ and ___
phospholipids and lipopolysaccharides
Peptidoglycan is made of ___ and ___
Amino acids and sugars
Describe the basic function of peptidoglycan in bacterial cell walls
Protects the bacteria from the host’s immune system
Prokaryotes don’t have any ____
membrane bound organelles
The cell wall and membrane forms the ___ in prokaryotes
envelope
Briefly compare the structures of prokaryote and eukaryote flagella
Prokaryote: 3 segments of basal body, hook, and filament
Eukaryotes: 9+2 microtubule structure
True or false: as plasmids carry external DNA for some prokaryotes, they are consider part of the bacteria’s genome
False: this DNA is external and not needed for the prokaryote’s survival
In a prokaryotic cell, the \_\_\_\_ is used for the electron transport chain and ATP generation: A) nucleus B) mitochondria C) cell membrane D) cell wall
C
Binary fission results in ____
2 identical daughter cells
True or false: mitosis is quicker than binary fission?
False; binary fission is quicker than mitosis
Define virulence factors
Traits found on plasmids that increase the pathogenicity of plasmids
Define and classify episomes
A subset of plasmids that integrate into the bacterial genome
List the and describe the recombination processes
1) Transformation: integration of foreign genetic info into the host genome from nearby lysed bacteria
2) Conjugation: sexual reproduction of 2 bacteria
3) Transduction: vectors carry genetic information from one bacterium to another
Briefly describe the mechanisms of conjugation in prokaryotic cells
The sexual reproduction of 2 bacteria from the unidirectional transfer of info from the male to female via the conjugation bridge
In prokaryotic conjugation, + denotes ____ bacteria while - denotes ____ bacteria
\+ = male - = female
In prokaryotic conjugation, + bacteria form the conjugation bridge from ____
Sex pili
Sex pili on + bacteria are made by _____
Genetic material on sex factors
Describe E coli conjugation and the role of sex factors
Cells that do not have the fertility factor (F-) become F+ when already existing F+ cells copy and donate their factors, so that new F+ cells can transfer its own copies
Define transposons
Genetic elements capable of inserting and removing themselves from genomes
True or false: transposons are seen with both eukaryotes and prokaryotes
True
Viral genetic info is:
- a) circular or b) linear
- a) single stranded or b) double stranded
- a) DNA or b) RNA
Can be all of the above
Define positive sense RNA
Viral RNA that is directly translated into proteins by ribosomes in the cytoplasm of the host cell
Define negative sense RNA
Viral RNA that utilizes its own RNA strand and RNA replicase to act as the template of the synthesis of a complementary strand, which in turn is the template of protein synthesis
Are protein coated or non-protein coated viruses easier to kill?
Protein coated
Define virions
Viral progeny
Describe the structure of bacteriophages
Capsid, tail sheath to inject info, tail fibers to recognize and connect to host
Define retrovirus and name an example
Enveloped, single stranded RNA viruses that carry reverse transcriptase to synthesize DNA, which is then integrated into the host nucleus (i.e. HIV)
Name 3 ways progeny can be released from a bacteria
Spilling out from the bacteria after cell death, bacterial lysing, extrusion
Define the 2 possible cycles of a bacteriophage
1) Lytic: the bacteriophage maximizes the usage of to host, which causes it to lyse
2) Lysogenic: the bacteriophage integrates into the host genome as a provirus/prophage
What stage are virulent viruses in?
Lytic phase
Define prions and name an example
Proteins that cause protein misfolding, typically in the alpha-helical to beta-pleated sheet, causing protein aggregation; mad cow disease
Define viroid and name an example
Pathogens of short, circular single-stranded RNA that binds to RNA sequences and silences genes, preventing protein synthesis; most common in plants, Hepatitis D is a human example