WEEK 3 Flashcards
Forms the cell’s flexible outer surface, separating the cell’s internal environment from the external environment.
Plasma Membrane
Consists of all the cellular contents between the plasma membrane and the nucleus.
Cytoplasm
Fluid portion of the cytoplasm, also called intracellular fluid, contains water, dissolved solutes, and suspended particles
Cytosol
Little organs of the cell with a specific shape and specific functions.
Organelles
A large organelle that houses most of a cell’s DNA.
Nucleus
A single molecule of DNA associate with several proteins, contains thousands of hereditary units.
Chromosomes
Hereditary units that control most aspects of cellular structure and function
Genes
According to this model, the molecular arrangement of the plasma membrane resembles a continually moving sea of fluid lipids that contains a mosaic of many different proteins.
Fluid Mosaic Model
Basic structural framework of the plasma membrane. Two back-to-back layers made up to three types of lipid molecules: phospholipids, cholesterol, glycolipids
Lipid Bilayer
Lipids that contain phosphorous
Phospholipids
A steroid with an attached -OH(hydroxyl) group
Cholesterol
Lipids with attached carbohydrate groups
Glycolipids
Both nonpolar and polar
Amphipathic
Extend into or through the lipid bilayer and are firmly embedded in it.
Integral Proteins
Type of integral proteins that span the entire lipid bilayer and protrude into both the cytosol and extracellular fluid
Transmembrane Proteins
Proteins that are not firmly embedded in the membrane. Attached to the polar heads of membrane lipids or to integral proteins at the inner or outer surface of the membrane
Peripheral Proteins
Type of integral proteins with carbohydrate groups attached to the ends that protrude into the extracellular fluid
Glycoproteins
Carbohydrate portions of glycolipids and glycoproteins form an extensive sugary coat called
Glycocalyx
Integral protein that forms a pore through which a specific ion can flow to get across membrane.
Ion Channel
Integral protein that transports a specific substance across membrane by undergoing a change in shape
Carrier
Integral protein that recognizes specific ligand and alters cell’s function in some way
Receptor
Integral and peripheral protein that catalyzes reactions inside or outside the cell
Enzyme
Integral and peripheral protein that anchors filaments inside and outside the plasma membrane, providing structural stability and shape for the cell.
Linker
Glycoprotein that distinguishes your cells from anyone else’s
Cell Identity Marker
Most of the membrane lipids and many of the membrane proteins easily rotate and move sideways in their own half of the bilayer. What characteristic of the membrane is this?
Membrane Fluidity
A structure that permits the passage of substances through it
Permeable
A structure that does not permit the passage of substances through it
Impermeable
The characteristic of a membrane that allows/inhibits substances to pass through it
Membrane Permeability
Property of membrane permeability to permit some substances to pass more readily than others
Selective Permeability
A difference in the concentration of a chemical from one place to another
Concentration Gradient
A difference in electrical charges between two regions
Electrical Gradient
Because the electrical gradient occurs across the plasma membrane, this charge difference is termed?
Membrane Potential
The combined influence of the concentration gradient and the electrical gradient on movement of a particular ion is referred to as
Electrochemical Gradient
A substance moves down its concentration or electrical gradient to cross the membrane using only its own kinetic energy
Passive Process
Cellular energy is used to drive the substance “uphill” against its concentration or electrical gradient
Active Transport
Tiny, spherical membrane sacs that substances used to enter and leave cells in an active process
Vesicles
What principle learns why materials diffuse across membranes requires an understanding of how diffusion occurs in a solution?
The Principle of Diffusion
A passive process in which the random mixing of particles in a solution occurs because of the particle’s kinetic energy
Diffusion
A factor that influences the diffusion rate of substances across plasma membranes. The greater the difference in concentration between the two sides of the membrane, the higher the rate of diffusion.
Steepness of the Concentration Gradient
A factor that influences the diffusion rate of substances across plasma membranes. The hotter it is, the faster the rate of diffusion
Temperature
A factor that influences the diffusion rate of substances across plasma membranes. Smaller molecules diffuse more rapidly than larger ones
Mass of the Diffusing Substance
A factor that influences the diffusion rate of substances across plasma membranes. The larger the area is, the faster the diffusion rate.
Surface Area
A factor that influences the diffusion rate of substances across plasma membranes. The farther the area of diffusion must occur, the longer it takes
Diffusion Distance
A passive process in which substances move freely through the lipid bilayer of the plasma membranes without the help of membrane transport proteins.
Simple Diffusion
Solutes that are too polar or highly charged to move through the lipid bilayer by simple diffusion can cross the plasma membrane by a passive process called
Facilitated Diffusion
In this type of diffusion, a solute moves down its concentration gradient across the lipid bilayer through a membrane channel
Channel-mediated Facilitated Diffusion
A carrier moves a solute down its concentration gradient across the plasma membrane
Carrier-mediated Facilitated Diffusion
Glucose enters many body cells by binding to a specific type of carrier protein called the?
Glucose Transporter
A type of diffusion in which there is a net movement of a solvent through a selectively permeable membrane
Osmosis
During osmosis, water molecules pass through a plasma membrane by moving through what bro? These are integral membrane proteins that function as water channels
Aquaporins or AQPs
Pressure exerted by a liquid
Hydrostatic Pressure
The solution with the impermeable solute exerts a force called what bro?
Osmotic Pressure
A measure of the solution’s ability to change the volume of cells by altering their water content
Tonicity
Any solution in which a cell maintains its normal shape and volume
Isotonic Solution
A solution that has a lower concentration of solutes
Hypotonic Solution
A solution that has a higher concentration of solutes
Hypertonic Solution
Shrinkage of cells
Crenation
Liquids infused into the blood of a vein
Intravenous Solutions(IV)
Energy derived from hydrolysis of ATP changes the shape of a carrier protein, which “pumps” a substance across a plasma membrane against its concentration gradient
Primary Active Transport
Carrier proteins that mediate primary active transport are called what fool?
Pumps
This carrier moves Na+ and K+ during primary active transport; another name for this is the Na+-K+ ATPase
Sodium-potassium Pump
Type of active transport. The energy stored in a Na+ or H+ concentration gradient is used to drive other substances across the membrane against their own concentration gradients.
Secondary Active Transport
These transporters move two substances in the same direction
Symporters
These transporters move two substances in opposite directions across the membrane
Antiporters
Often given to patients with heart failure
Digitalis
During this, materials move into a cell in a vesicle formed from the plasma membrane
Endocytosis
During this, materials move out of a cell by the fusion with the plasma membrane of vesicles formed inside the cell
Exocytosis
A highly selective type of endocytosis by which cells take up specific ligands
Receptor-mediate Endocytosis
Receptor-mediated endocytosis of LDLs occurs as follows: On the extracellular side of the plasma membrane, an LDL particle that contains cholesterol binds to a specific receptor in the plasma membrane to form a receptor-LDL complex. chuchuchu clathrin attaches to the membrane on its cytoplasmic side chuchuchu
Binding
Receptor-mediated endocytosis of LDLs occurs as follows: The invaginated edges of the membrane around the clathrin-coated pit fuse, and a small piece of the membrane pinches off.
Vesicle Formation
This vesicle contains the receptor-LDL complexes
Clathrin-coated Vesicle
Receptor-mediated endocytosis of LDLs occurs as follows: After the clathrin-coated vesicle is formed, it loses its clathrin coat t become an uncoated vesicle.
Uncoating
Receptor-mediated endocytosis of LDLs occurs as follows: The uncoated vesicle quickly fuses with a vesicle known as an endosome. Within an endosome, the LDL particles separate from their receptors
Fusion with endosome
Receptor-mediated endocytosis of LDLs occurs as follows: Most of the receptors accumulate in elongated protrusions of the endosome. These pinch off, forming transport vesicles that return the receptors to the plasma membrane. LDL receptor is returned to plasma membrane
Recycling of receptors to plasma membrane
Other transport vesicles, which contain the LDL particles, bud off the endosome and soo nfuse with a lysosome.
Degradation in Lysosomes
“Cell-eating”; form of endocytosis in which the cell engulfs large solid particles, such as worn-out cells, whole bacteria, or viruses
Phagocytosis
A few body cells able to carry out phagocytosis
Phagocytes
Projections of the plasma membrane and cytoplasm after phagocytosis begins
Pseudopods
“Cell-drinking” a form of endocytosis in which tiny droplets of extracellular fluid are taken up.
Bulk-phase Endocytosis/Pinocytosis
membrane-enclosed vesicle that forms inside the cell, fuse with the plasma membrane, and release their contents into the extracellular fluid
Secretory Vesicles
successively move a substance into, across, and out of a cell
Transcytosis
A network of protein filaments that extends throughout the cytosol
Cytoskeleton
Thinnest element of the cytoskeleton. Composed of proteins actin and myosin and are most prevalent at the edge of a cell.
Microfilaments
Cell extensions. Nonmotile, microscopic fingerlike projections of the plasma membrane.
Microvilli
Thicker than microfilaments but thinner than microtubules.
Intermediate Filaments
Largest of the cytoskeletal components. Long, unbranched hollow tubes composed mainly of the protein tubulin
Microtubules
Located near the nucleus, consists of two components. A pair of centrioles and the pericentriolar matrix. AKA microtubule organizing center
Centrosome
2 cylindrical structures, each composed of nine clusters of three microtubules arranged in a circular pattern
Centrioles
Contains hundreds of ring-shaped complexes composed of the protein tubulin
Pericentriolar Matrix
numerous, short, hairlike projections that extend from the surface of the cell
Cilia
similar to cilia but are much longer. Generates forward motion along its axis by rapidly wiggling in a wavelike pattern
Flagella
The sites of protein synthesis. High content of one type of RNA
Ribosomes
A network of membranes in the form of flattened sacs or tubules. Has two distinct forms
Endoplasmic Reticulum
Studded with ribosomes. Synthesizes proteins
Rough ER
not studded with ribosomes. Contains unique enzymes. Synthesizes fatty acids and steroids
Smooth ER
Most of the proteins synthesized by ribosomes attached to the rough ER are transported to other regions of the cell. This organelle is the first step in the transport pathway.
Golgi Complex
small, flattened membranous sacs with bulging edges that resemble a stack of pita bread
Cisterns
Is a convex cistern that faces the rough ER
Entry(cis) face
is a concave cistern that faces the plasma membrane
Exit(trans) face
Sacs between the entry and exit faces are called
Medial Cisterns
Membrane-enclosed vesicles that form from the Golgi complex. Can contain as many as 60 kinds of powerful digestive and hydrolytic enzymes that can break down a wide variety of molecules once lysosomes fuse with vesicles formed during endocytosis
Lysosomes
The process by which entire worn-ou organelles are digested
Autophagy
In autophagy, the organelle to be digested is enclosed by a membrane derived from the ER to create a vesicle called::?
Autophagosome
Lysosomal enzymes may also destroy the entire cell that contains them. What process is this?
Autolysis
Group of organelles similar in structure to lysosomes, but smaller.
Peroxisomes
Enzymes that can oxidize various organic substances
Oxidases
Continuous destruction of unneeded, damages, or faulty proteins is the function of tiny barrel-shaped structures consisting of four stacked rings of proteins around a central core called
Proteasomes
Powerhouse of the cell; Generates ATP through aerobic respiration
Mitochondria
The internal mitochondrial membrane contains a series of folds called
Mitochondrial Cristae
The central fluid-filled cavity of a mitochondrion, enclosed by the internal mitochondrial membrane is called
Mitochondrial Matrix
Programmed cell death
Apoptosis
Double membrane that separates the nucleus from the cytoplasm
Nuclear Envelope
Opening that extend through the nuclear envelope
Nuclear Pores
Spherical bodies that function in producing ribosomes
Nucleoli
Complex of DNA proteins and some RNA is called
Chromatin
Total genetic information carried in a cell or organism is called
Genome
Consists of double-stranded DNA wrapped twice around a core of eight proteins
Nucleosome
A core of eight proteins which help organize the coiling and folding of DNA
Histones
The string between the beads is called
Linker DNA
The study of the relationships between the genome and the biological functions of an organism
Genomics
Refers to all of an organism’s proteins
Proteome
In this process, a gene’s DNA is used as a template for synthesis of a specific protein.
Gene Expression
In this part of gene expression, the genetic information represented by the sequence of base triplets in DNA serves as a template for copying the information into a complementary sequence of codons. Occurs in nucleus
Transcription
In this part of gene expression, the nucleotide sequence in an mRNA molecule specifies the amino acid sequence of a protein. Occurs in cytoplasm
Translation
A sequence of three nucleotides in DNA
Base Triplet
Specifies a particular amino acid
Codon
Set of rules that relate the base triplet sequence of DNA to the corresponding codons of RNA and the amino they specify
Genetic Code
Type of RNA that directs the synthesis of a protein
Messenger RNA mRNA
Type of RNA that joins with ribosomal proteins to make ribosomes
Ribosomal RNA rRNA
Type of RNA that binds to an amino acid and holds it in place on a ribosome until it is incorporated into a protein during translation
Transfer RNA tRNA
One end of the tRNA that consists of a triplet of nucleotides called
Anticodon
Catalyzes transcription of DNA
RNA polymerase
A special nucleotide sequence located at the beginning of a gene
Promoter
Transcription of the DNA strand ends at another special nucleotide sequence called
Terminator
Regions within a gene that do not code for parts of a protein
Introns
Regions that code for segments of a protein
Exons
Immediately after transcription, the transcript includes information from both introns and exons and is called
Pre-mRNA
Removes introns from pre-mRNA
Small Nuclear Ribonucleoproteins
The _ site binds the tRNA carrying the growing polypeptide chain
P(peptidyl) site
The _ site binds the tRNA carrying the growing polypeptide chain
A aminoacyl
The _ site binds tRNA just before it is released from the ribosome
E(exit)
Special tRNA binds to the start codon on mRNA, where translation begins. Now tell me, what is this special tRNA that I speak of?
Initiator tRNA
Several ribosomes attached to the same mRNA
Polyribosome
The process by which cells reproduce themselves
Cell Division
Is any cell of the body other than a germ cell
Somatic Cell
A gamete or any precursor cell destined to become a gamete
Germ Cell
In this type of cell division, the cell undergoes a nuclear division called mitosis and a cytoplasmic division called cytokinesis
Somatic Cell Division
Mechanism that produces gametes
Reproductive Cell Division
Orderly sequence of events in which a somatic cell duplicated its contents and divides in two
Cell Cycle
What are the two chromosomes that make up each pair called?
Homologous Chromosomes
A pair of chromosomes designated as X and Y. Do not look similar.
Sex Chromosomes
Somatic cells contain two sets of chromosomes, what are they called?
Diploid(2n) Cells
Phase of cell division. Cell replicated its DNA, and produces additional organelles and cytosolic components. State of high metabolic activity; most growing time. Consists of 3 phases.
Interphase
The interval between the mitotic phase and the S phase. Cell replicates most of its organelles and cytosolic components but not its DNA
G1 phase
Cells that remain in the G1 phase for a very long time, perhaps destined to never divide again
G0 Phase
Interval between G1 and G2. DNA replication occurs
S Phase
Interval between S phase and mitotic phase. Cell growth continues, enzymes and other proteins are synthesized in preparation for cell division, and replication of centrosomes is complete
G2 Phase
Results in the formation of two identical cells; consists of a nuclear division and a cytoplasmic division to form two identical cells.
Mitotic phase
The distribution of two sets of chromosomes into two separate nuclei. This process results in the exact partitioning of genetic information
Nuclear Division/Mitosis
The chromatin fibers condense and shorten into chromosomes that are visible under the light microscope.
Prophase
At the outside of each centromere is a protein complex known as
Kinetochore
A football-shaped assembly of microtubules that attach to the kinetochore
Mitotic Spindle
During this phase of mitosis, the microtubules of the mitotic spindle align the centromeres of the chromatid pairs at the exact center of the mitotic spindle
Metaphase
The plane of alignment formed during metaphase
Metaphase Plate
During this phase of mitosis, the centromeres split, separating the two members of each chromatid pair, which move toward opposite poles of the cell
Anaphase
The final stage of mitosis begins after chromosomal movement stops. The identical sets of chromosomes, now at opposite poles of the cell, uncoil and revert to the threadlike chromatin form. A nuclear envelope forms around each chromatin mass.
Telophase
Division of a cell’s cytoplasm and organelles into two identical cells
Cytokinesis
Cytokinesis begins in late anaphase with the formation of a slight indentation of the plasma membrane. What is this formation called?
Cleavage Furrow
Enzymes that can transfer a phosphate group from ATP to a protein to activate the protein
Cyclin-dependent Protein Kinases (Cdk’s)
Switches the Cdk’s on and off
Cyclins
Pathological type of cell death that results from tissue injury
Necrosis
The reproductive cell division that occurs in the gonads
Meiosis
Gametes have only half the number of chromosomes, what is it called
Haploid (n) cells
Beings once chromosomal replication is complete. Consists of four phases
Meiosis I
Extended phase in which the chromosomes shorten and thicken, the nuclear envelope and nucleoli disappear, and the mitotic spindle forms
Prophase i
An event in which two sister chromatids of each pair of homologous chromosomes pair off
Synapsis
The resulting four chromatids from synapsis form a structure called
Tetrad
Parts of the chromatids of two homologous chromosomes may be exchanged with one another. What is this exchange between nonsister chromatids called?
Crossing-over
The formation of new combinations of genes
Genetic Recombination
Second stage of meiosis. During this stage, each of the two haploid cells formed during meiosis I divides; net result is four haploid gametes that are genetically different from the original diploid starting cell
Meiosis II
The sizes of cells are measured in units called
Micrometers
Normal process accompanied by a progressive alteration of the body’s homeostatic adaptive responses.
Aging
Specialized branch of medicine that deals with the medical problems and care of elderly persons
Geriatrics
Scientific study of the process and problems associated with againg
Gerontology
Specific DNA sequences found only at the tips of each chromosome. Protect the tips of chromosomes from erosion and from sticking to one another
Telomeres
A group of diseases characterized by uncontrolled or abnormal cell division
Cancer
When cells in a part of the body divide without control, the excess tissue that develops is called
Tumor
The study of tumors
Oncology
A cancerous neoplasm is called
Malignant Tumor/Malignancy
The spread of cancerous cells to other parts of the body
Metastasis
A neoplasm that does not metastasize
Benign Tumor
Malignant tumors that arise from epithelial cells
Carcinomas
Cancerous growths of melanocytes
Melanomas
General term for any cancer arising from muscle cells or connective tissues
Sarcoma
The most frequent type of childhood cancer that destroys normal bone tissue
Osteogenic Sarcoma
A cancer of blood-forming organs characterized by rapid growth of abnormal leukocytes (WBC)
Leukemia
Malignant disease of lymphatic tissue
Lymphoma
The growth of new networks of blood cells
Angiogenesis
Cancers that have a viral origin
Oncogenic Viruses
A multistep process of cancer development in which as many as 10 distinct mutations may have to accumulate in a cell before it becomes cancerous
Carcinogenesis
Potential treatment for cancer that is currently under development. The use of viruses to kill cancer cells
Virotherapy
The loss of tissue differentiation and function that is characteristic of most malignancies
Anaplasia
A decrease in the size of cells, with a subsequent decrease in the size of the affected tissue or organ
Atrophy
Alteration in the size, shape, and organization of cells due to chronic irritation or inflammation
Dysplasia
Increase in the number of cells of a tissue due to an increase in the frequency of cell division
Hyperplasia
Increase in the size of cells without cell division
Hypertrophy
Transformation of one type of cell into another
Metaplasia
Offspring or Descendants. Babies
Progeny
The study of the proteome in order to identify all of the proteins produced
Proteomics
A substance introduced into circulation by tumor cells that indicated the presence of a tumor
Tumor Markerrrrrrrrrrrrrrrr HUMANA KOOOOOOOOOOOO
