CELL Flashcards
explores molecular mechanisms of normal cellular processes as well as diseases.
Biochemistry
TRUE OR FALSE:
All higher living organisms including humans are made up of cells
TRUE
TRUE OR FALSE:
Fundamental unit of life; All biochemical processes are carried out by cells
TRUE
Two Major Classes of Cells
Prokaryotes
Eukaryotes
was the first person to use the term “cell”
Robert Hooke
He referred to the small empty chambers in the structure of cork as cells
Robert Hooke
concluded that all plant and animal tissues were composed of cells.
Matthias Schleiden and Theodor Schwann
Responsible of Cell Theory
Matthias Schleiden and Theodor Schwann
proposed the theory of biogenesis where cells only arise from pre-existing cells.
Rudolf Virchow
“A cell is the basic structural and functional unit of living organisms.”
Cell Theory
The activity of an organism depends on the collective activities of its cells
Classes of Cells:
DNA is found in the nucleus of the cell: responsible for storage of DNA
Eukaryotes
Classes of Cells:
Contain membrane-bound organelles: mitochondria, endoplasmic reticulum, and Golgi complex
Eukaryotes
Classes of Cells:
Cell division involves mitosis (sexual)
Eukaryotes
Classes of Cells:
DNA is not enclosed within the membrane (scattered)
Prokaryotes
Classes of Cells:
Lack membrane-enclosed organelles
Prokaryotes
Classes of Cells:
Usually divided by binary fission (asexual)- (cytokinesis)
Prokaryotes
Molecular Composition of Cell:
accounts for about 70-75% of the weight of the cell/ body
Water
Molecular Composition of Cell:
account for 25-30% of the cell weight.
Organic compounds (Nucleic acids, proteins, polysaccharides (carbohydrates) and lipids.)
Molecular Composition of Cell:
account for the rest of the cell weight.
Inorganic compounds
Electrolytes, ions, salt, potassium, manganese
TRUE OR FALSE:
Eukaryotic cells have a membrane-bound nucleus and a number of other membrane-bound subcellular (internal) organelles
TRUE
Cell Parts:
Phospholipid bilayer containing lipids, cholesterol and proteins and some carbohydrates (glycolipids, glycoproteins)
Plasma Membrane (Perimeter of the cell)
Common lipid present in plasma membrane
phospholipid
Property of plasma membrane (hydrophilic and hydrophobic)
Amphipathic
Cell Parts:
Acts as a physical barrier to enclose cell contents
Plasma Membrane (Perimeter of the cell)
Cell Parts:
Regulates material movement into and out of the cell
Plasma Membrane (Perimeter of the cell)
Cell Parts:
Functions in cell communication w/ the environment and other cells
Plasma Membrane (Perimeter of the cell)
Cell Parts:
Largest and most obvious membrane-bound compartment of the cell
Nucleus (Control center)
It contains the DNA that serves as the genetic material for directing protein synthesis.
Cell Parts:
Where chromosomes are seen: DNA coiled around Histone= chromatin
Nucleus (Control center)
Cell Parts:
It is enclosed within a double membrane called nuclear envelope
Nucleus (Control center)
Parts of Nucleus:
It consists of RNA and proteins which function in ribosomal unit assembly.
Nucleolus
Parts of Nucleus:
It surrounds the chromatin (Histone + DNA) and the nucleoli.
Nucleoplasm
Cell Parts:
Enclosed by cell membrane but not part of any organelle
Cytoplasm
Interior contents of the cell
Part of Cytoplasm:
Provides support for organelles and serves as the viscous fluid medium
Where organelles, ribosomes, and metabolic enzymes float
Cytosol
Cell Parts:
it holds diff organelles and has ribosomes (protein synthesis) and metabolic enzymes
Cytoplasm
Cell Parts:
Powerhouse of the cell; responsible for the production of ATP (adenosine triphosphate)
Mitochondria (similar w/ prokaryotes)
TRUE OR FALSE:
Mitochondria have their own DNA
TRUE
Mitochondrial DNA: similar to prokaryotic DNA
TRUE OR FALSE:
Mitochondria have their own ribosomes
TRUE
similar w/ the construction of prokaryotic ribosome
TRUE OR FALSE:
Mitochondria can synthesize their own protein but not all
TRUE
TRUE OR FALSE:
Mitochondria replicate on their own by binary fission
TRUE
Theory that states that mitochondria is considered an aerobic bacteria that was ingested by the cell
Endosymbiotic theory
Structures of Mitochondria:
Highly permeable to small molecules
Outer membrane
Due to the presence of a pore-forming protein called porin
Structures of Mitochondria:
Contains many proteins that participate in oxidative phosphorylation(i.e. one group is replaced by phosphate group)
Intermembrane
Structures of Mitochondria:
Has multiple folds projecting inwards called cristae
Inner membrane
Structures of Mitochondria:
spaces found w/in mitochondria
Matrix & intermembrane
Cell Parts:
It is responsible for the production of energy in the form of ATP (adenosine triphosphate)
Mitochondria
Cell Parts:
Scavenger of the cell/ Suicide bag
Lysosomes
Cell Parts:
Formed from the golgi apparatus
Lysosomes
cell eating, process when particles are engulfed by the cell and those that are needed will be digested/ degraded
Phagocytosis
Cell Parts:
Contains digestive enzymes, for digesting foreign materials
Responsible for intracellular digestion
Lysosomes
(The fluid inside lysosomes is much more acidic: about pH 4.8, than the normal pH of about 7.0–7.3) e.g. Acid hydrolase
Cell Parts:
Digest microbes or materials by the cell
Lysosomes
Cell Parts:
Web-like series membrane w/in the cytoplasm w/c has the flatten sheets, sacks, tubes
Endoplasmic Reticulum
Ribosomes can be found in:
RER, mitochondria, cytoplasm, nucleus (nucleolus)
Subdivision of ER:
Site of protein synthesis because of the ribosomes that are found
Rough endoplasmic reticulum
Subdivision of ER:
Modifies, transports, and stores proteins produced by attached ribosomes
Rough endoplasmic reticulum
Subdivision of ER:
Site for lipid synthesis (steroids, fatty acids, cholesterols)
Smooth endoplasmic reticulum
Subdivision of ER:
provides for diff enzymatic activities (detoxification, calcium storage, production of lipids)
Smooth endoplasmic reticulum
Cell Parts:
series of several elongated, flattened saclike membranous structures.
Golgi Apparatus (Packaging house of the cell/ Post Office)
Cell Parts:
Modifies, packages, and sorts materials, that arrive from the endoplasmic reticulum in transport vesicles
Golgi Apparatus
Regions of Golgi Apparatus:
entry of material, fuse w/ transport vesicles from ER
Cis
Regions of Golgi Apparatus:
middle, where packaging of proteins happen
Medial
Regions of Golgi Apparatus:
exit, budding off/ detaching of secretory vesicles
Trans
Cell Parts:
Smaller, spherical membrane bound organelles formed from the endoplasmic reticulum (ER)
Peroxisomes
Cell Parts:
Detoxify specific harmful substances: produced/ taken by the cell
Peroxisomes
Produces hydrogen peroxide (H2O2) thru oxidation and converted into water and oxygen
Cell Parts:
Contain reducing enzymes: catalase or oxidase
Peroxisomes
Cell Parts:
Organized network of protein filaments
Cytoskeleton
Scaffolding of protein
Cell Parts:
Maintains integral structural support and organization of cells
Responsible for the transportation of the materials
Positioning and movement of organelles, and in the change of cell shape
Cytoskeleton
3 Components of Cytoskeleton:
Smallest components;
Involved in cell movements and membrane deformations
Microfilaments/ Actin filaments
maintain cell shape
3 Components of Cytoskeleton:
Made of stranded protein fibers
Anchor organelles/ neighbor cells to each other, transport of membranes w/in the cytoplasm
Intermediate filaments (give mechanical support to structures: nucleus and plasma membrane)
3 Components of Cytoskeleton:
Hollow tubules made up of tubulin (proteins)
Responsible for cell movement and movement of organelles
Microtubules (provides structural support)
3 Components of Cytoskeleton:
Largest component of cytoskeleton
Involved in cell division
Microtubules
Produced by centrioles
Classes of Cell:
(Eubacteria and Archaebacteria) are the most abundant organisms on earth
Prokaryotes
TRUE OR FALSE:
A prokaryotic cell does not contain a membrane-bound nucleus.
TRUE
TRUE OR FALSE:
Each organelle of eukaryotic cells is surrounded by a plasma membrane.
TRUE
TRUE OR FALSE:
The cell has no subcellular organelles, only have mesosomes (folding of the plasma membrane)
TRUE
TRUE OR FALSE:
Prokaryotes: Only contains infoldings of the plasma membrane called mesosomes.
TRUE
TRUE OR FALSE:
The (DNA) is condensed within the cytosol to form the nucleoid.
TRUE
TRUE OR FALSE:
Some prokaryotes have tail-like flagella. Majority are bacteria
TRUE
is the movement of a substance from an area of its higher concentration to an area of its lower concentration.
Diffusion
No energy is consumed during the transport
is the type of diffusion of dissolved solutes through the plasma membrane
Simple diffusion
is the type of diffusion that requires a protein carrier
Facilitated Diffusion
is the diffusion of water point across a selectively permeable membrane
Osmosis
This type of cell membrane transport uses energy (ATP) provided by the cell
Active Transport Process
This type of cell membrane transport does not require energy
Passive Transport Process
Sodium vs Potassium:
extracellular cation, found inside the cell, pairs w/ chloride (major extracellular anion)
Sodium
Sodium vs Potassium:
intracellular cation, outside of the cell
Potassium
Refers to bulk movement of substance out of the cell by fusion of secretory vesicles with the plasma membrane
Exocytosis
Dumping of secretory vesicle out of cell
Refers to bulk movement of substance into the cells by vesicles forming at the plasma membrane
Endocytosis
Pinocytosis, Phagocytosis, Receptor -mediated endocytosis
Binds 3 sodium and molecules of ATP, one phosphate group will bind through the channel
Active Transport: Sodium-Potassium Pump
Cell Life Cycle:
It is the longest phase of the cell cycle where the cell is active and preparing for cell division
Interphase
Phases: G1 (longest, cells are metabolically active), S, G2 (cells are ready to enter cell division)
Cell Life Cycle:
The DNA molecule is duplicated exactly in a process called DNA replication which occurs toward the end of the interphase
Interphase
Cell Life Cycle:
Cells arise from the division of other cells. Chromosomes will be visible
Cell Division
Cell Life Cycle:
consists of four stages: prophase, metaphase, anaphase, and telophase.
Mitosis
Nuclear Division/ Karyokinesis:
each chromosome consists of two chromatids joined at the centromere
Prophase
Longest stage. Chromosomes condense for it to become visible
Nuclear Division/ Karyokinesis:
chromosomes align at the center of the cell (equatorial plate) via microtubules
Metaphase (Chromosomes shorten )
Chromosomes are observed if there are abnormalities
Nuclear Division/ Karyokinesis:
chromatids separate at the centromere and migrate to opposite poles.
Anaphase
Shortest stage. Division of chromosomes
Nuclear Division/ Karyokinesis:
two new nuclei assume their normal structure
Cell division is completed
Telophase
Splitting of two new daughter cells (cytokinesis, have own plasma membrane)