HT LC U1 Flashcards
also called microscopic anatomy because of the small details that comprises that comprises the tissues
Histology
study of tissues of the body and how they are arranged to constitute organs
Histology
First to identify a tissue without the use of a microscope
Marie Bichat
when and where the first microscopes were constructed
1500s, Netherlands
actual inventor of microscope
Zacharias Janssen
who invented the first microscope with high magnification and good image quality
Anthony van Leeuwenhoek
membrane bound structures within cells
Organelles
How cells combine together with extracellular material and each other to form a tissue
Tissue structure
How a cell is shaped, and how the components inside cells are organized to support that cells specific function
Cellular structure
detailed analysis of organelles and inclusions
Sub-cellular structure
molecular analysis of cellular structure
Histochemical structure
special proteins called enzymes which enhances a chemical reaction
Catalysts
particular structures (usually proteins) that can be synthesized by certain cells like plasma cells so they can produce antibodies which will be utilized by the lymphatic system to fight foreign bodies
Antigency
credited with creating the first “histology” that was based on a detailed examination of tissues with the microscope
Friedrich Gustav Jacob Henle
4 basic types of tissue
Epithelial, Connective, Muscle, and Nervous
Characteristics of matrix
Rubber, stony or gelatinous
begins as a single cell that divides into many cells that form layers
Embryo
Difference of the Three Primary Germ Layers
- Ectoderem - outer; epidermis + nervous system
- Mesoderm - middle; forms mesenchyme, gives rise to muscle, bone and blood; connective tissues and muscle
- Endoderm - inner; mucous membranes and respiratory linings; GI tract and respiratory
reduces a 3-dimensional structure to a 2-dimensional slice
Sectioning
Difference of the 3 types of sections
- Longitudinal - along the longest direction of an organ
- Cross - perpendicular to the length of an organ
- Oblique - between cross and longitudinal
Characteristics of epithelial tissue
- one or more layers of closely adhering cells
- top : flat sheet with upper apical surface
- bottom : sits on top of basement membrane
Characteristics of Connective Tissue
- most abundant and variable tissue type
- consists of gelatinous (ground) and fibers with widely spaced cells
Functions of Connective Tissue
binding of organs, support, protection movement, storage and transport
Three types of muscle tissue
Skeletal muscle, cardiac muscle and smooth muscle
T/F Skeletal muscle completely depends on signaling from the nervous system to work properly.
TRUE
T/F Both cardiac and smooth muscle types can respond to other stimuli, such as hormones and local stimuli.
TRUE
Two types of cells which compose nervous tissue
Neurons and Glial Cells
Maintain the extracellular environment around neurons, improve signal conduction in neurons and protect them from pathogens
Glial Cells
T/F Staining patterns differ according to the histochemical properties which are brought about by the molecular structures that mainly make up a tissue
True
Small biologic entity capable of independent existence
Cell
Fertilized cell that undergoes a series of mitotic division and eventually differentiating to form a blastocyte to become a full human being
Zygote
Cell constructed by imagination to include parts which are found in the other cells
Hypothetical Cell
T/F A cell will not work well if it has only the essentials to support its functions and its existence
False
contains materials produced in the cell and formed by the Golgi apparatus
Organelles
site of ribosomes and messenger RNA synthesis and contains DNA
Nucleus
site of ribosomal RNA synthesis and ribosomal subunit assembly
Nucleolus
site of aerobic respiration and major site of ATP synthesis
Mitochondria
Difference of 3 compartments of the mitochondria
Outer membrane
Inner membrane - cristae which consists of matrix
Mitochondrial matrix - sites of aerobic respiration where energy is produced
primary site of secretory protein synthesis and where many ribosomes are attached to
Rough Endoplasmic Reticulum
site of lipid biosynthesis , steroid hormone synthesis, intracellular calcium storage, and for detoxification of oxious metaabolites
Smooth Endoplasmic Reticulum
Role of SER in the skeletal muscle and endocrine glands
Skeletal muscle - used for release and capture of calcium ions
Endocrine organs - synthesis of steroidal hormones
for protein synthesis
Ribosomes
Two types of ribosomes
- Fixed (Attached) - adheres to the members of the ER
- Free (Polysomes) - free floating or scattered in the cytosol
contains enzymes that digest material taken into the cell and turnover cell components
Lysosome
Two types of Lysosomes
- Primary lysosomes - small membrane bound vesicles containing hydrolytic enzymes - quiet ones
- Secondary lysosomes - formed by the fusion of primary lysosome & a phagocytized foreign body
supports the cytoplasm and forms components of cilia and flagella
Microtubules
specialized structure that increase surface area of certain cells
Microvilli
help organize the assembly of microtubules during cell division
Centrioles
modifies protein structure and packages proteins in secretory vesicles; involved in protein synthesis
Golgi Apparatus
3 parts of the Factory Assembly Line of Golgi A.
- Cis Face - face and site of integration of vesicle from RER; entry site from ER (convex)
- Medial or Intermediate Face - product manufactured in the RER
- Trans Face of Golgi - maturing face; proteins transported to extracellular to CM or intracellular to organelles (concave)
Contains materials produced in the cell and formed by the golgi apparatus
Secretory Vesicles
For proper management of metabolic waste products of the cell
Peroxisome
Transitory components of the cytoplasm and important for the normal functioning of the cell
Cytoplasmic deposits
3 Cytoskeletal Components
- Microfilaments - cell movement and endocytosis
- Intermediate Filaments - structural function/support
- Microtubules - development and maintenance of cell shape
permeability barrier that allows cell to maintain an interior composition far from the extracellular fluid
Cell Membrane
T/F The phospholipid bilayer has a hydrophobic head and a hydrophilic tail.
False
2 Proposed Structure of Cell Membrane
- Trilaminar Structure - has bilipid layer sandwiched between two layers of protein
- Fluid Mosaic Model - globular proteins are compared to icebergs floating on a sea of lipids
creates kinks and prevents close packing of hydrophobic tails
Unsaturated Fatty Acid
stabilize and regulate the fluidity of the phospholipid bilayer
Cholesterol
carbohydrate moieties functions as receptors or antigen
Glycolipids
3 Types of Membrane Proteins
- Peripheral Proteins - found on the cytoplasmic side of the inner leaflet
- Intrinsic/Integral Proteins - segment embedded in one of the leaflets with a lipid anchor
- Transmembrane Protein - span the lipid bilayer; function on both sides of the bilayer
2 Layers of the Cell
- Apical Region - faces lumen, connects to ducts and has channels (outer)
- Basolateral Region - faces capillary containing tissue; cells attached to underlying connective tissue
T/F The functional molecules are those that can create proteins, cytoskeleton, and other organelles found in the cytoplasm.
True
contains code for all of cell’s enzymes and the command/control center of the cell
Nucleus
separates the nucleoplasm and isa a double set of membranes with a narrow perinuclear space
Nuclear Envelope
penetrates the nuclear envelope and are large assemblies of nucleoporins
Nuclear Pore Complexes
intermediate filament subunits that support the nuclear envelope
Lamins
DNA organized into fibrous material
Chromatin
chromatin fibers which coil up as separate structures
Chromosomes
double layered structure and has gaps
Nuclear Membrane
maintains the continuity oof transport of material between cytosol and nucleus
Nuclear Pore
segment of DNA that codes for a polypeptide or a particular protein
Human gene
combination of DNA and its associated proteins
Chromatin
basic proteins that wraps around the DNA molecule
Histones
extra X chromosome in cells of female mammals
Barr body
Difference of Chromatin and Chromosome
Chromatin - coiled strands of DNA and associated histone protein
Chromosome - tightly packed DNA that are found during cell division
Components of chromatin
DNA, histones, DNA binding proteins, and RNA
Difference of Heterochromatin and Euchromatin
Heterochromatin - transcriptionally inactive; 10% chromatin
Euchromatin - transcriptionally active; 90% chromatin
Two Type of Heterochromatin
Constitutive - Stable heterochromatic; regions of Y chromosome
Facultative - Reversible heterochromatic state; regions of X chromosome
basophilic or eletron-dense area of chromatin localized where rRNA transcription and ribosomal subunits assembly occur
Nucleolus
Subregions of active nucleolus
Fibrillar - site of transcription
Granular - assembly of rRNA
important in maintenance of cell shape and plays a special role in tissue identification and disease diagnosis
Cytoskeleton
Four phases of the cell cycle
G1 Phase, S Phase, G2 Phase, M Phase
gap between mitosis and beginning of DNA replication
G1 phase
period of DNA synthesis
S phase
gap between DNA duplication and next mitosis
G2 Phase
cell activities are temporarily or permanently suspended
G0 Phase
regulate the overall cycling in the cell and activates CDKs
Cyclin
4 Cell Cycle Checkpoints
- G1 Checkpoint - check DNA replication, cell size, nutrients, DNA damage and growth factors
- Intra S-phase Checkpoint - check DNA damage and DNA replication
- G2/M Checkpoint - checks DNA replication
- Mitotic Checkpoint - checks chromosome attachment and alignment
core components of the cell cycle machinery and promotes progression through cell cycles
Cyclin-dependent kinases (CDKs)
3 Types of Cells in the Cell Cycle
- Permanent Cells - will never reenter the cell cycle
- Labile Cells - keep on recycling/regenerating new cells
- Stable Cells - remain in G0 phase and dies easily
Phases of Mitosis
- Interphase - long period between mitoses
- Prophase - chromatin condenses, centromere binds together chromatids
- Metaphase - chromosomes condense further, microtubules move to equatorial plate
- Anaphase - sister chromatids separate and move to opposite poles
- Telophase - two sets of chromosomes at spindle poles revert to uncondensed; deepened cleavage furrow
Two key features of Meiosis
- Synapsis - double strand breaks and repairs in DNA and crossover happen to produce new combination of genes
- Cells produced are haploid - chromosome present in body’s somatic cells
Phases of Meiosis
Meiosis I - Late Interphase, Prophase I, Metaphase I, Anaphase/Telophase I
Meiosis II - Metaphase II, Anaphase II / Telophase II
