Module 1: cells Flashcards
Define a cell
basic unit of life
What is the cell theory
basic units of living organization and function in all organisms and all cells come from other cells
Define plasma membrane function
surrounds cell: contains pump and gate: regulate passage of material in/out
3 differences between prokaryotic and eukaryotic cells
Prokaryotic: no nucleus: simple
- ) small then eukaryotic cells: visible with light scope
- ) DNA is not enclosed in nuclear membrane
- ) Doesn’t contain many of internal membrane bound organelles
where does metabolic process occur in prokaryotic cells
plasma membrane
What do ribosomes do in prokaryotic cells
synthesize protein composed of RNA
Define Endospore
durable cell that can lie dormant: often released by bacteria under adverse conditions
What are eukaryotic cells
10-100x larger than prokaryotic have nuclear membrane and nucleus have membrane bound organelles nucleus surrounded by nuclear envelope Nucleus contains DNA and control center of cell
Define chromosome
packaged and organized form of DNA in a cell
Define Gene
material that determines which proteins synthesized in ribosome
What is mRNA and what is its function
messenger RNA
transfer DNA to ribosome
what is rRNA and its function
ribosomal RNA: takes and transfers ribosomes: synthesized in nucleolus
What is a ribosome and its function
looks like small granule: contain rRNA and enzyme to form protein from amino acid
tiny plant cell assemble protein
What is endoplasmic reticulum( ER)
maze of tightly packed sac like structure that forms compartments in cytoplasm-
changes when ribosomes are present
extension of outer membrane of nucleus
What is SER and RER
smooth endoplasmic reticulum and rough endoplasmic reticulum
“rough” because ribosome are present
“smooth” synthesizes lipids
Both have enzymes that catalyze chemical reactions
Cytoplasm( cytosol) define
fluid portion of nucleus and all organelles outside of nucleus
Define Golgi Complex
an organelle made up of a stack of flattened cisterna
What is function of Gogi Complex
responsible for receiving lipid and protein synthesized by ER, alter the structure and ships to other parts of the cell
Define a Lysosome and its function
small sac of digestive enzyme produced by golgi complex
breaks down biomacromolecules that originate outside/insdie of cell: protein, lipid, carb, nucleic acid
Once broken into building blocks-> molecules made into new biomacromolecules
also can fuse with other vesicle containing harmful bacteria and destroy its componenets
What is Tay-Sachs
genetic condition in which the digestive enzyme is lacking inside lysosome causing a buildup of lipid in the brain
if left untreated can cause intellectual disability or death
What are mitochondria
organelle responsible for converting chemical energy from food into ATP
What is ATP
Adenosine Triphosphate: fuel for most cellular chemical reactions
What is aerobic cellular respiration
oxygen is required to break down food
CO2, H20 and ATP are produced
further process of breaking down food into ATP to be used
Define cytoskeleton
protein fibers provide structural support and movement in cell
What is inter membrane space
between inner/outer membrane: has many folds which increase surface area, allowing ample room for chemical reaction to transfer energy in food to ATP
What are microtubules
Microtubules: hollow cylinder: move chromosome in cell division instruct cilia and flagella to project from cells
What are cilia
short, many found in humans along respiratory passageway for trapping and moving debris
What are flagella
long whip like structure: typically found on sperm
What is a centriole
9 sets of 3 attached tubules arranged to form a hollow center- similar to flagella
What are microfilaments
flexible, solid fibers made of 2 intertwine polymer chains of actin molecules: has 2 daughter cells: myosin and actin: cause muscle contraction
What is a cell coat
made up of polysaccharide side chains, project out of protein, lipid which equal cell membrane
do plant and animal cells have a cell wall
yes and contain cellulose
Do bacteria cell walls have cellulose
no- they have peptidoglycan
What is a light microscope
compound: has several lenses- light must pass through the speciman
What is a electron microscope
microscope magnifies 250,000x resolution of 10,000x of human eye
transmission microscope
specimen cut into thin sections- each passed under electron bean forms image on photographic plate or fluorescent screen
Scanning microscope
produces 3D picture
What is phospholipid bilayer
2 component: lipid and protein
what is structure and function of lipid bilayer
amphipathic layer with polar( hydrophilic head) and hydrophobic tail
heads face out because attracted to H20
tails are fluid motion: allow lipid to rotate and move
What is cholesterol
stabilizer against heat and cold
What are different proteins within phospholipid bilayer
integral: span across lipid bilayer
peripheral: located on outer/inner surface of membrane
What is selective permeability
allow select materials to pass through membrane only going one way
nutrient go in/ waste goes out
what are the 3 methods for crossing selective permeable membrane
diffusion, active transport, endocytosis and exocytosis
What is diffusion
small particle move from area of large concentration to small concentration
flow continues until evenly distributed
occurs naturally when particle collide: also named passive transport( perfume)
What is concentration gradient
difference in concentration of a substance from one place to another
What is osmosis
diffusion of water: 3 terms for relationship between water and solute solution: isotonic, hypotonic, hypertonic
What is isotonic
equal amount of solute on either side membrane
what is hypotonic
solute outside of cell is less than inside: water is higher outside of cell-> causes water to move inward-> increases size of cell
What is hypertonic
solute outside of cell is more than inside: water is lower inside of cell than outside-> movement of water naturally flow from greater concentration ( inside the cell) to lower outside
What is facilitated diffusion
diffusion of lipid soluble molecule across a membrane- usually by integral proteins
What is active transport
molecule pumped from area of lower concentration to an area of higher concentration
requires more energy as molecules don’t like to move this way
Sodium Potassium Pump define
maintain electrical imbalance across the membrane
important in cell life
ions: because polar in nature need protein to chess membrane
Function of Sodium Potassium Pump
ATP is needed as cells keep (Na+) to outside of cell after diffusing in
Phosphate from ATP bind to carrier protein-> change protein shape and enable Na+ to be released outside membrane
K+ actively returned to inside of cell after being diffused outside-> accomplished by K+ ion bind to carrier protein, change shape to origin
As shape changes: allows phosphate group and K+ ion released into cell
Active transport maintains gradient
Pump maintains electrical gradient across membrane which used to conduct nerve impulses
What are biomacromolecules
ex: protein, nucleic acid, polysaccharide- because of lg size can’t move across membrane
What is exocytosis
process of biomacromolecule in vesicle fuses with cell membrane ejecting it from the cell: exos= going out
What is endocytosis
process of biomacromolecule outside of cell in cell membrane forms vesicle in cell: endo=bring in:
What are the 3 methods of endocytosis and describe each one
Phagocytosis: endocytosis of lg objects-> cell enclosed in vesicle, fuses with lysosome inside cell and digested
Pinocytosis: endocytosis of tiny drops of fluid-> like phagocytosis-> cell membrane pinches inward w/o needing to use pseudopod to injest material
Receptor mediated endocytosis: proteins role in cell membrane: info is transferred from one cell to another
How do proteins aid in receptor mediated endocytosis
Integral binds with ligand( signal protein)
Integral responsible for transfer
Ligand= changes shape and enzymes activated
Enzymes catalyze energy release from ATP which powers cell
