The Cell (Focus) Flashcards
the structural and functional unit of the living body
Cell
Unit membrane having the “fluid mosaic model” and semi permeable membrane
Cell Membrane
Forms a thin loose covering over the entire surface of the cell membrane
Glycocalyx
surface of the cell membrane attached with proteins
Glycoproteins
surface of the cell membrane attached with lipids
Glycolipids
Provide route for diffusion of water-soluble substance like glucose and electrolytes
Channel Proteins
Transport of substance across the cell membrane
Carrier Proteins
Serves as receptor sites for hormones and neurotransmitters
Receptor proteins
Induce the process of antibody formation
Antigen
Control chemical reactions within the cell membrane
Enzymes
Substance move from the region of higher concentration to the region of lower concentration, without using ATP
Passive Transport/Diffusion/Downhill Movement
Exchange of oxygen and carbon dioxide between blood and body tissues
Simple Diffusion
Carrier proteins help the transport of substance
Facilitated Diffusion
Movement of water/fluid or any other solvent from an area of lower concentration of solute to an area of higher concentration of solute through a semipermeable membrane
OSMOSIS
Movement of substance against the chemical or electrical or electrochemical gradient. requires energy which is obtained mainly by breakdown of ATP
Active Transport
Bulk movement of substance out of the cell by fusion of secretory vesicles with the plasma membrane
Exocytosis
Bulk movement of substances into the cell by vesicles forming at the plasma membrane
Endocytosis
vesicles are formed as particulate materials external to the cell are engulfed by pseudopodia “Cell eating”
Phagocytosis
Vesicle are formed as interstitial fluid is taken by the cell “Cell Drinking”
Pinocytosis
form an interconnected network which forms the link between the organelles and cell membrane
Endoplasmic Reticulum
Attachment of the granular ribosome also gives the beaded or granular appearance and concerned with the protein synthesis in the cell
Rough ER
processing and delivery of substances like proteins and lipids to different parts of the cell, also known as “Post office, Shipping department” of the cell
GOLGI APPARATUS
Removal of excess secretory products by degrading the secretory granules, “Digestive system of the Cell”
Lysosomes
In melanocytes, secretory lysosomes secrete:
Melanin
In Mast cells, secretory lysosomes secrete ________ which is an inflammatory mediator
Serotonin
Degrade the toxic substances line hydrogen peroxide and other metabolic product by means of “Detoxification”, breakdown the excess fatty acids, accelerate gluconeogenesis from fats.
Peroxisomes
responsible for the movement of chromosomes during cell division
Centrioles
Situated near the center of the cell close to the nucleus
Centrosome
“Powerhouse of the Cell” ATP
Mitochondria
Involved in protein synthesis, organelles composed of both protein and ribosomal RNA, Protein factories of the cell.
RIBOSOMES
Determine the shape and structural strength of the cell, separation of chromosomes.
MICROTUBULES
Division of the cytoplasm, give structural strength to the cell.
Microfilament
Short, numerous membrane extensions supported by microtubules, found in trachea, bronchioles, primary bronchi, fallopian tube.
CILIA
Caused by a defect in the action of cilia, characterized by recurrent upper and lower respiratory tract infections, also called “immotile cilia syndrome”
Kartagener Syndrome
Long, singular membrane extension supported by microtubules, present on sperm cells, moves in quasi-sinusoidal waves
Flagella/Flagellum
Increase membrane surface area for greater absorption, brush border appearance/characteristics.
Microvilli
Most abundant in epidermis of the skin and retina
Melanin
Large structure enclosed within a double membrane with openings, houses the DNA that serves as the genetic material for DNA replication and direct protein synthesis
Nucleus
Double membrane boundary between cytoplasm and nuclear contents
Nuclear envelope
“Chromatin” - Made of a double stranded helical structure of DNA and proteins and also called “beads on string appearance” is?
Histones
Function of histones
Guides the coiling of DNA
Thread like structure that carry genetic information; contains a single double-stranded DNA molecule
Chromosome
Cloverleaf structure contains an anticodon triplet of bases to base pair. delivers amino acids to ribosome
tRNA
Carries the genetic information of DNA and directs protein synthesis
mRNA
Integral component of ribosomes, site of protein synthesis.
rRNA
“DNA to RNA” process which DNA serves as template for the assembly of molecules of RNA.
Transcription
“DNA to DNA” process of completely duplicating DNA within cell
Replication
Process in making proteins & polypeptide from mRNA
Translation
Code for amino acids and collectively determine the amino acid sequence of the protein product, represented in final mature of mRNA Molecule
Exons
Portion of the gene that do not code for amino acids, removed (spliced) from the mRNA molecule before translation
Introns
“1st growth Phase”
Cellular contents, excluding the chromosomes, are duplicated
G1 Phase
DNA synthesis
S Phase
Resting Phase where the cell has left the cycle and stopped dividing
G0 phase
Division of DNA/Somatic cells to make two daughter cells with copies of original genome— diploid (2n)
Mitosis “Karyokinesis”
Phases: Chromosome condense, centrioles move to opposite poles.
PROPHASE
Phases: Spindle fibers align chromosomes along midline to cell to form metaphase plate. “Align at the equator of the cell”
Metaphase
Phases: Spindle fibers shorten to separate chromatids, pulling them to either end of cell. Chromosome SPLIT going towards opposite poles.
Anaphase
Formation of a new nuclear membrane containing diploid (2n) chromosomes
Telophase
Cytoplasm divides into two
Cytokinesis
any deviation in the number of chromosomes, whether fewer or more, from the normal haploid number of chromosomes.
Aneuploidy
most common chromosomal disorder
Trisomy 21
Characterized by an extra copy of chromosome 18. 47, XY, +18
oral findings: Micrognathia
Trisomy 18 (Edward’s Syndrome)
Characterized by an extra copy of chromosome 13.
Patau Syndrome
One of the most common causes of male hypogonadism. Characterized by two or more X chromosomes and one or more Y Chromosomes.
Clinical Findings: Atrophic, underdeveloped testes, gynecomastia, tall stature, and a lower IQ, “Bulls Teeth” - Taurodontism
Klinefelter Syndrome
One of the most important causes amenorrhea. Characterized by having only one X chromosome, with a total of 45 chr. and a karyotype of XO
Turners Syndrome
Also known as Mandibulofacial Dysostosis, results from abnormal development of derivatives from the 1st and 2nd branchial arches.
Treacher Collin Syndrome
develops from epithelial cells
Carcinoma
develops from mesenchymal cells
Sarcoma
There is a loss of differentiation in these cells
Anaplasia
Cells and their nuclei can appear in various forms and shapes
Pleomorphism
Programmed cell death, “Cell suicide”
Apoptosis
uncontrolled and unprogrammed death of cells due to unexpected and accidental damage. Ex. Injury, infection, inflammation, infarction and cancer.
Necrosis
Associated commonly with hypoxic or ischemic death of cells
Coagulation Necrosis
Coagulation necrosis happens in all cell tissues except:
BRAIN
Characterized by softening and liquefaction of the injured tissue, commonly found in the brain following the cutting off of the blood supply
Liquefaction Necrosis
accumulation of a cheeselike material. most often encountered in tuberculous infections.
Caseous Necrosis
Results in the enzymatic breakdown of fat cells and the subsequent formation and deposition of calcium-fatty acid complexes
Fatty Necrosis
Deposition of calcium salts in dead or degenerating tissues or in scar tissue
Dystrophic Calcifications
Precipitation of calcium salts within previously undamaged tissues, develops in association with increased level of calcium
Metastatic Calcifications
Complete absence of an organ or tissue
Agenesis
“almost” complete failure of development
Aplasia
Failure of an organ to develop completely
Hypoplasia
Reduction in the size of organ or tissue as a result of a decrease in either the size or component the cell
Atrophy
Increase in cell size so that the affected organ or tissue is enlarged without an increase in the number of cells
Hypertrophy - Best seen in striated muscle: Cardiac and skeletal
Enlargement of tissues or organs as a result of an increase in the number of constituent cells
Hyperplasia
One type of adult cell is replaced by another adult cell type, Qualitative alterations is the major feature.
Metaplasia
Regression to more primitive cell types with loss of structural and functional differentiatation of the cells
Anaplasia
Tumorlike malformation which represents a non-neoplastic developmental condition
Hamartoma
most common type of cell degeneration
Cloudy Swelling
- Swelling is related to increased concentration of intracellular water and sodium, Opaque, soft consistency.
Abnormal accumulation of lipid in parenchymal cells, organs exhibits remarkable enlargement with a soft yellow and greasy cut surface
Fatty Degeneration
Characterized by intracytoplasmic accumulation of a hyaline substance in injured cells
Hyaline Degeneration
Abnormal Ig production with extracellular accumulation of immunoglobulin light chains in tissues
Amyloid Degeneration
Defined as the connection between neighboring cells or the contact between the cell and extracellular matrix
Cellular Junctions “Membrane Junction”
Attaches cells of the same type, seen between epidermis and between cardiac muscles.
Desmosomes / “Spot-weld-like or Macula Adherens”
Cell to matrix junction, Attaches cells of different type. Seen between Epidermal cells and basement membrane, Junctional Epi. and Tooth surface.
Hemidesmosomes