Week One Flashcards
Histology?
The study of the tissues of the body and how they are arranged to constitute organs
Four types of tissue?
Muscle
Neural
Epithelial
Connective
Epithelial tissue characteristics?
- Aggregated polyhedral cells
- Small amount of ECM
- Lining of surface or body cavities
- Glandular secretion
Connective tissue characteristics?
- Several types of fixed and wandering cells
- Greatest amount of ECM
- Support and protection of tissues
Nervous tissue characteristics?
- Elongated cells with extremely fine processes.
- Very small amount of ECM
- Transmission of nerve impulses
Muscle tissue characteristics?
- Elongated contractile cells
- Moderate amount of ECM
- Strong contraction, body movements
Some reasons disease occur?
- Spontaneous alteraton to a cells ability to proliferate and function.
- External stimuli make it impossible for cell to maintain homeostasis.
Hyperplasia
More cells
Hypertrophy
Growth in terms of cell size
Atrophy
Smaller cells ( can be size and number)
Metaplasia
Mature differentiated cell transforms into different mature cell type. Reversible
Example: Barrett’s Esophagus
Dysplasia
Tissue develops large number of immature cells. Extremely disordered growth, precancerous, pleomorphism.
What is the plasma membrane?
Phospholipid bilayer
Semipermeable (selective)
Hydrophilic head
hydrophobic and lipophilic tail
What do fibroblasts make?
Make the ECM
Types of connective tissue
Bone
Cartilage
Ligaments and tendons
What does the interstitial fluid within CT do?
Gives metabolic support to the cells as the medium for diffusion of nutrients and waste products.
What does the ECM consist of?
Protein fibers like collagen and elastic fibers and ground substance.
What does GAG make?
Hyaluronic acid
What is the strongest and most abundant protein fiber in ECM?
Collagen
Where does all CT originate from?
Embryonic Mesenchyme
What does Mesenchyme consist of?
Undifferentiated cells, generally elongated, large nuclei and prominent nucleoli.
In all types of CT what exceeds the volume of the cells?
The ECM volume
What is the most common CT cell?
Fibroblast
Where are muscle cells derived from?
Mesoderm
How do muscle cells differentiate?
By lengthening and synthesizing myofibrillar proteins like actin and myosin.
What are the three types of muscle tissue?
Skeletal (Bicep)
Smooth (intestinal tract)
Cardiac
Properties of muscle tissue
Electrical excitability (acetylcholine/ electricity)
Contractibility
Extensibility
Elasticity
What causes contraction?
Sliding of thick myosin filaments with thin actin filaments
What is the cytoplasm of muscle cells called?
Sarcoplasm
What does the Sarco- prefix indicate
Muscle
Skeletal muscle characteristics?
Bundles of long, multinucleated cells with cross striations. Voluntarily controlled
Cardiac muscle characteristics?
Cross- striations and is composed of elongated, often branched cells bound to one another at intercalated discs. Involuntary contraction.
Why are intercalated discs important?
Facilitate coordinated contraction
Smooth muscle characteristics?
Consists of fusiform cells DOES NOT have striations, slow involuntary contractions
Two main groups of epithelial tissue?
Covering (lining) epithelia
Secretory (glandular) epithelia
Simple
One layer
Stratified
More than one layer
What do epithelia line?
All external and internal surfaces of the body
What must all substances that enter or leave an organ cross?
Epithelia
Apical
Exposed/ specialized
Basal
Basement/ adhered
Cuboidal cell example
Testes
Columnar cells example
Digestive tract
Squamous cells example
Cervix
Where does the epithelial typically receive nutrients from?
The blood vessels contained within the adjacent CT that provide nutrients and O2
What is the CT that underlies the epithelial lining of the digestive, respiratory, and urinary systems called?
Lamina propria
Papillae occur most frequently where?
In epithelial tissues subject to friction, like the skin or tongue.
What does the stratum corneum contain
Dead cells
Stratum Lucidum characteristics?
Not always present, clear thick skin seen on the palms and bottom of the feet.
Stratum granulosum characteristics?
This is where cells begin to die and dehydrate.
Stratum spinosum characteristics?
Contains mitotic cells, dendritic cells (langerhans)/ immunocompetent cells.
Stratum Basale
deepest layer of epithelium, new skin cell development
State the order top to bottom
Come - Stratum corneum
Lets - Stratum lucidum
Get - Stratum granulosum
Sun - Stratum spinosum
Burnt - Stratum basale
Cell Function: Facilitates movement, active transport by pinocytosis, secretion. Simple
Squamous Simple
Examples of distribution: endothelium, pericardium, pleura, peritoneum
Squamous Simple
Cell Function: covering, secretion, Simple
Cuboidal Simple
Examples of distribution: Covering the ovary, thyroid
Cuboidal Simple
Cell Function: Protection, lubrication, absorption, secretion. Simple
Columnar Simple
Examples of distribution: Lining of intestine and gallbladder
Columnar Simple
Cell function: protection, prevents water loss.
Squamous (keratinized) Stratified
Examples of distribution: Epidermis
Squamous (keratinized) Stratified
Cell function: Protection, secretion, prevents water loss.
Squamous (Non-keratinized) Stratified
Examples of distribution: Mouth, esophagus, larynx, vagina, anal canal
Squamous (non-keratinized) Stratified
Cell function: Protection, secretion
Cuboidal Stratified
Example of distribution: Sweat glands, developing ovarian follicles.
Cuboidal Stratified
Cell function: Protection, distensibility
Transitional
Examples of distribution: Bladder, ureters, renal calyces.
Transitional
Cell function: Protection
Columnar stratified
Examples of distribution: Conjunctiva
Columnar stratified
Cell function: Protection, secretion, cilia mediated transport of particles trapped in mucus, out of the air passages.
Pseudostratified
Examples of distribution: Lining of trachea, bronchi, nasal cavity.
Pseudostratified
The ability of specialized cells to respond to stimuli
excitability
What is the cell body of a neuron called?
Soma
What does a nucleolus do?
Process rRNA and produces ribosomes in the nucleus.
Signals going out =
Axon
Signals coming in =
Dendrite
Where do dendrites extend from?
The soma
What are the small branches of the axon called?
Telodendria
What is the knob like structure that forms connections?
Synapse
What is the axon covered in?
Myelin sheath
What does myelin do?
Insulate the signal and decrease degradation.
Myelin cells of the peripheral nervous system
Schwann cells
Myelin cell of the central nervous system
Oligodendrocytes
What is the space in between Myelin?
Nodes
What makes up the largest percentage of body weight intracellular or interstitial fluid?
Intracellular!
What makes up the smallest percentage of body weight?
Blood plasma
If salinity is too high what happens to the cells?
Crenation- cells atrophy and collapse
High in NaCl and low in K
Extracellular fluid
What is extracellular fluid made of?
Interstitial fluid and blood plasma
Low in NaCl and high in K
Intracellular fluid
Cell murder
Necrosis
Cell suicide
Apoptosis
Adaption to non-homeostatic conditions can manifest as?
Hyperplasia, Hypertrophy, Dysplasia (tumors)
When cells cannot adapt to non-homeostatic conditions we see?
Necrosis, apoptosis
Name the normal cell adaption: increase breast tissue size during pregnancy.
Hyperplasia
Name the pathologic cell adaption: Proliferation of endometrium due to prolonged E2 stimulus.
Hyperplasia
Name the normal cell adaption: Enlargement of skeletal muscle with exercise.
Hypertrophy
Name the pathologic cell adaption: Enlargement of the heart due to aortic stenosis.
Hypertrophy
Name the normal cell adaption: Decrease in the size of the uterus after pregnancy
Atrophy
Name the pathologic cell adaption: Kidney shrinking because atherosclerosis of renal artery resulting in ischemia.
Atrophy
Neoplasia
New growth
Benign Neoplasm from glandular cells
Adenoma
Malignant neoplasm from epithelial cells
Carcinoma
Malignant neoplasm from mesenchymal cells
Sarcoma
Malignant neoplasm from lymphocytes
Lymphoma
Malignant neoplasm from melanocytes
Melanoma
Generally ends in JUST OMA
Benign neoplasms (so many exceptions do not rely on this)
Generally ends in Sarcoma or Carcinoma
Malignant neoplasms
Benign neoplasm of smooth muscle
leiomyoma
Malignant neoplasm of smooth muscle
Leiomyosarcoma
Well differentiated
Resemble cells they differentiated from
Moderately differentiated
Some cells look the same some do not
Poorly differentiated
Cell origin is hard to recognize (WORST)
Anaplasia
Lack of differentiation, makes it difficult to know the origin of the tumor.
Cells show many nuclei or distorted shapes
Pleomorphism
Hamartoma
Not a neoplasm, an abnormal growth that’s made up of the same tissue from which it grows.
Choristoma
Not a neoplasm, mass composed of ectopic tissue. Not abnormal tissue, but in an abnormal place.
Polyp
A mass projecting from mucosal tissue.
Characteristics of malignant tissue?
Pleomorphism, hyperchromatic, hypercellularity. Abnormal mitotic figures.
Pleomorphism
Variation in nuclear and cytoplasmic shape
Hyperchromasia
Increase basophilia of nucleus, increased staining of nuclei (darker).
Hypercellularity
A loss of normal polarity (symmetry)
What is growth fraction?
The proportion of neoplastic cells in the proliferative phase
Infiltration of tumor cells into surrounding tissue is called?
Invasion
What is the spread of tumor cells to different organs through blood or lymph.
Metastasis
Characteristic of sarcomas
Metastasizes through blood
Chracteristic of Carcinomas
Metastasizes through lymph
Passage through the cell cycle is highly regulated at what checkpoints?
G1/S boundary
G2/M boundary
What is the checkpoint called during mitosis?
Spindle checkpoint
Regulation is achieved via the activity of what?
Protein kinases
Genes of critical proteins in the control process that are targeted by cancer?
Tumor suppressor genes
Almost every cancer shows we have an issue with which checkpoint?
G1/S
Malignant neoplasms result from the survival of cells that have accumulated multiple what?
Mutations
Types of genes that are commonly affected in carcinogenesis
Proto-oncogenes, tumor suppressor genes, apoptosis genes, DNA repair genes
What are Proto-oncogenes?
commonly used during normal cell growth and development.
What is an Oncogene
A proto-oncogene that has mutated to cause uncontrolled cell growth.
What do tumor suppressor genes do?
Help control cell growth
First step of cell invasion
Cell adhesion to the basement membrane
second step of cell invasion
Local proteolysis of cell membrane
Third step of cell invasion
Movement of the cell through the opened membrane and the ECM.
The ability for tumor cells to survive and expand in the novel microenvironment of the metastatic site.
The rate- limiting step.
When cells lose contact with the ECM and undergo apoptosis it is called?
anoikis-apoptosis
