Cell Basics Flashcards
What is the central dogma of molecular biology?
DNA undergoes transcription to become RNA and RNA undergoes transcription to become protein
What is differentiation?
The process during development in which cells become specialized
Why are red blood cells a terminal cell type?
They lack DNA, therefore are unable to divide and have limited repair capabilities
What is the primary reason for which red blood cells have no cell nucleus or organelles?
This feature evolved to accommodate maximum hemoglobin carrying capacity
What is enculeation?
The mechanism by which maturing red blood cells eject their nucleus
What does the term abiogenesis refer to?
The chemical origin of life
What was the Miller-Urey experiment?
A chemical experiment that stimulated the conditions thought to exist on the early earth and tested the chemical origin of life under those conditions
What is the primordial soup hypothesis?
The conditions on the primitive earth favoured chemical reactions that synthesized more complex organic compounds from simpler organic precursors
T or F: amino acids can be generated in conditions that mimic those of early earth.
True
What are the three main things that are needed to make a cell?
- Information
- Chemistry
- Compartments
How are cellular compartments usually defined?
By a single or double lipid membrane
What are the two fundamental roles of cellular compartments?
- Establish physical boundaries that enable the cell to carry out different metabolic activities
- Generate a micro-environment to spatially and temporally regulate biological processes
What term was coined by Robert Hooke?
“Cell”
What theory was proposed by Jakob Schleiden and Theodor Schwann and later added to by Rudolf Virchow?
The cell theory
What are the three tenants of the cell theory?
- All living organisms are composed of one or more cells
- The cell is the most basic unit of life
- All cells arise from pre-existing cells
List 9 basic properties of cells
(S.C.C.C.R.E.A.M.S)
- Respond to STIMULI
- COMPLEX and organized
- CONTROLLED by a genetic program
- Carry out CHEMICAL reactions
- REPRODUCE/make copies of themselves
- Able to EVOLVE
- ASSIMILATE and utilize energy
- Engage in MECHANICAL ACTIVITIES
- Capable of SELF-REGULATION
What is considered to be the most important distinction among groups of organisms?
The distinction between prokaryotes and eukaryotes
What is the main difference between prokaryotes and eukaryotes?
Prokaryotes lack a defined nucleus
Are archaea and bacteria classified as prokaryotes or eukaryotes?
Prokaryotes
What type of cells are present in single-cell organisms?
Prokaryotes
Where is genetic material found in prokaryotic cells?
In a nucleoid
How do prokaryotes reproduce?
Asexually
Are protozoa, fungi, plants, and animal cells classified as prokaryotes or eukaryotes?
Eukaryotes
Are eukaryotic cells found in multicellular organisms, unicellular organisms, or both?
Both (often multicellular)
Where is genetic material found in eukaryotic cells, and how is it arranged?
Found in a nuclear compartment and is arranged as chromosomes
Are slime molds prokaryotic or eukaryotic?
Eukaryotic
Under which kingdom are slime molds categorized?
Kingdom Protista
T or F: Slime molds are multicellular organisms.
False. They are single-celled.
How do slime molds reproduce?
They use spores to reproduce sexually
Are slime molds uninucleated or multinucleated?
Multinucleated
Which organelle controls the movement of molecules in and out of the cell?
The plasma membrane
Which organelle generates ATP by oxidizing glucose and fatty acids?
The mitochondria
Which organelle degrades material internalized by the cell, as well as worn-out cellular membranes and organelles?
Lysosomes
Which component of the cell encloses the contents of the nucleus and is continuous with the rough ER?
The nuclear envelope
What is the nuclear subcompartment where most of the cell’s rRNA is synthesized?
The nucleolus
Which organelle is filled with chromatin composed of DNA and proteins?
The nucleus
Where are mRNA and tRNA synthesized?
The nucleus
Which component of the cell contains enzymes that synthesize lipids and detoxify certain hydrophobic molecules?
The smooth endoplasmic reticulum
Which component of the cell functions in the synthesis, processing and sorting of secreted proteins, lysosomal proteins, and certain membrane proteins?
The rough endoplasmic reticulum
Which organelle processes and sorts secreted proteins, lysosomal proteins, and membrane proteins synthesized in the rough ER?
The Golgi complex
What is the role of secretory vesicles?
Store secreted proteins and fuse with the plasma membrane to release their contents
What do peroxisomes contain?
Contain enzymes that break down fatty acids into smaller molecules used for biosynthesis
Which cell component contains fibres that form networks and bundles that support cellular membranes, help organize organelles, and participate in cell movement?
The cytoskeleton
What is the primary role of microvilli?
Increase surface area for absorption of nutrients
Are microvilli unique to plant or animal cells?
Unique to animal cells
Are cell walls unique to plant or animal cells?
Plant
What are cell walls primarily composed of?
Cellulose
Are vacuoles unique to plant or animal cells?
Unique to plant cells
Are chloroplasts unique to plant or animal cells?
Unique to plant cells
Which organelle carries our photosynthesis?
Chloroplasts?
What are plasmodesmata?
Tube-like cell junctions that span the cell wall and connect the cytoplasms of adjacent plant cells
