Cell Biology 1 Flashcards
What do organelles allow the cell to do?
Grow, divide, and specialize
What is the city hall of the cell?
Nucleus
What is the nucleus responsible for?
DNA storage and transcription (blueprints for proteins)
Where is the nucleus located?
enclosed within the nuclear membrane
What is the powerhouse of the cell?
Mitochondria
What are mitochondria responsible for?
ATP production
T/F: Mitochondria have their own DNA.
T
What does the number of mitochondria indicate?
metabolic demands of the cell
What is the primary production plant of the cell?
Rough endoplasmic reticulum
What are RER studded with and what are their role?
ribosomes; synthesize proteins
The RER is continuous with what structure?
nuclear envelope
What is the accessory production plant of the cell?
Smooth endoplasmic reticulum
What is SER responsible for (2 things)?
lipid and steroid synthesis (cell membrane maintenance and communication) AND detox of cell
Differences between SER and RER (2)?
SER more tubular than RER and not continuous with nuclear envelope
Two functions of Golgi apparatus?
packages proteins in membrane-bound vesicles for transport, determines where the protein will go based on special sugar tag, GENERALLY allow cells to specialize
What is the post office of the cell?
Golgi apparatus
What are the recycling centers of the cell?
Lysosome and peroxisome
What are lysosomes composed of? Shape?
sphere full of enzymes
What are lysosomes responsible for?
hydrolyzing substances that cross the cell membrane (mostly proteins)
What type of pH do enzymes need in lysosomes to activate? WHY?
acidic; acts as a protective measure
What do peroxisomes do?
degrading fatty acids and ROS molecules
What is the fluid mosaic model?
plasma membrane is a mosaic of molecular components that move freely throughout the membrane
What are ROS?
reactive oxygen species, VERY damaging to cells
What are the four functions of the cell membrane? DEFINE them.
Exclusion- keep things out
Consumption- bring in nutrients
Excretion- cellular waste/hormones
Communication- physically/chemically
Pneumonic: ECEC
What are the four primary components of the plasma membrane?
Phospholipids
Cholesterol
Proteins
Carbohydrates
Explain the components of the phospholipid bilayer.
Hydrophilic heads face outward
Hydrophobic tails face inward
What is the function of hydrophobic tails?
Form a waterproof barrier
What is the function of hydrophilic heads?
communication with intra and extra cellular fluids
What are the two types of proteins? Difference?
Integral and peripheral proteins
Integral have one hydrophobic region and peripheral do not have a hydrophobic region
What does cholesterol help with? HOW?
Maintains fluidity of membrane in fluctuating temperatures; stops phospholipids from packing too tightly in low temperatures AND maintains rigidity in high temperatures
What is the function of an integral protein’s hydrophobic region?
Keeps them anchored to the interior of the membrane
Where are peripheral proteins found?
Inside or outside of the cell membrane
Where are carbohydrates found? Bound to?
Outside of the membrane; bound to lipids or proteins
What is the function of peripheral proteins?
facilitate communication and coordination between cells
What are carbohydrates important for? Example?
intercellular communication and recognition; immune system function
What is simple diffusion?
movement of molecules down their conc gradient across the cell membrane
What transport utilizes diffusion? Definition?
Passive; particles move down their conc gradient from high to low
Two types of cellular transport? Difference?
Active and passive; actives requires energy
What is osmosis?
diffusion of water molecules from low solvent conc to high solvent conc
What direction do active transport particles move?
against their concentration gradients
What is facilitated diffusion?
diffusion that requires a membrane transport channel protein
What is primary active transport? Example?
the direct utilization of ATP for energy in order to transport particles across the cell membrane; Sodium-potassium pump
What is secondary active transport?
Use of the energy of one type of particle moving down its gradient to power another particle against its gradient
What are symporters?
move both types of molecules in the same direction across the membrane
What are antiporters?
Move the two types of molecules in opposite direction
What does secondary active transport require? Why?
primary active transport; to establish necessary gradients
Three types of protein filaments that comprise cytoskeleton from smallest to largest?
Microfilaments
Intermediate filaments
Microtubules
What are microfilaments? Functions?
thin strands of actin protein monomers; movements, structure, tracks for transport
What is cytoskeleton?
Network of filaments throughout the cell and cell membrane
Functions of cytoskeleton?
Support/Shape
Organization of organelles
Infrastructure for vesicular movement
Movement
What are tight junctions? Example?
Waterproof (impermeable barrier to separate fluids of either side of tissue), connection points between cells; epithelial tissue of the bladder
What are the functions of microtubules?
resist compression forces
aid in vesicular transport
form the spindle during mitosis
Shape, location, and function of gap junctions? Example?
donut shaped rings of transmembrane proteins, aligned between two cells, forms a channel that crosses the membrane of both cells connecting their cytoplasms; cardiomyocytes
What are spot welds formally known as?
desmosomes
What are intermediate filaments? Functions? Example?
thicker strands of proteins; bear tension, shape, keep organelles in place; keratin
Three different types of cell adhesion?
Gap junctions, desmosomes, tight junctions
Function of desmosomes? Example?
Allows for stretch without tearing, connection; keratinocytes
What are the three germ layers?
Endoderm, mesoderm, ectoderm
What layer is endoderm? Example of locations of endoderm?
Inner; GI tract, pulmonary system, thymus, liver, pancreas
What layer is mesoderm? Examples of locations found?
Middle; muscle, blood vessels, endocrine glands
Layer of ectoderm? Examples?
Outer; epidermis, hair, nasal cavity, mouth, anus
