Primary Tissues Flashcards
What are the 4 tissue types ?
Epithelial
Nervous
Muscle
Connective
Tissue
A group of specialised cells with a distinct function.
Differentiation
The process by which cells become specialised in structure and function.
Stem Cells
Unspecialised cells that retain the ability to become a wide variety of specialised cells. They undergo asymmetric division.
Where are stem cells found ?
In the early embryo (pluripotent)
They can also be found in tissues
What is an originator cell ?
A stem cell
What type of division do stem cells undergo ?
Asymmetric division
How is gene expression regulated ?
It is regulated by transcription factors.
Morphology types of tissue
Epithelial and Connective tissue
Function types of tissue
Muscles and Nerves
Is epithelial tissue vascular or avascular ?
Avascular
Function of platelets
Coagulation
In epithelial tissue where are nutrients and oxygen obtained from ?
Capillaries of the connective tissue which the basement membrane of the epithelial tissue rests.
Endothelium
Epithelium that lines the blood vessels and heart.
They are simple squamous.
Mesothelium
Epithelium that lines and encloses the constituents of body cavities, such as pericardial, abdominal and pleural cavities.
Primary Cilia
Found in most animal cells
Senses extracellular signals
Odorant/photoreceptor receptors found here
Motile Cilia
Responsible for cell movement
What are the 2 cell types that nervous tissue consists of ?
- Nerve cells
- Glial / Supporting cells
What are the 2 divisions of the nervous system ?
CNS
PNS
What is the structure of neurons ?
Dendrites
Cell body (SOMA)
Axon
Synapse
Axon end bulb
The site of chemical neurotransmitter release.
Function of dendrites
Direct stimulus towards the cell
Function of axon
Directs the stimulus away from the cell
How is neurotransmitter released and what happens after this ?
Neurotransmitter is released via exocytosis into the synaptic cleft.
These molecules are then moved along microtubules.
These stages require energy, so mitochondria release that in the form of ATP.
What are the 2 classes of glial cells in the CNS ?
Macroglia
Microglia
Macroglia cell examples
Oligodendrocytes
Schwann cells
Astrocytes
Microglia cell examples
Resident immune cells and phagocytes
What are the glial cells of the PNS ?
Schwann cells
Satellite cells
Schwann Cells
Involved in myelination
Satellite cells
Support cells in ganglia
Astrocytes
Most common type of glial cell in the CNS. They surround and insulate synapses.
Inactivation of glutamate to glutamine and recycling of glutamine
What are 3 types of muscle tissue ?
Skeletal
Cardiac
Smooth
Sacrolemma
Cell Membrane
Sacroplasm
Cytoplasm
- holds actin and myosin
What do all muscle tissues contain ?
Actin and Myosin
Skeletal Muscle Features
STRIATED
Multi-nucleated cells
Voluntary
Cardiac Muscle Features
STRIATED
Branched
Large number of mitochondria
Smooth Muscle Features
Non-Striated
Involuntary
Spindle shaped cells
Cell borders rarely seen
What are the 4 types of Connective Tissue ?
Fibrocollagenous Tissue
Cartilage, bone and teeth
Adipose tissue
Blood
Major Feature of connective tissues
Mix of different cells
Mix of extracellular matrix
What does the extracellular matrix contain ?
Fibrous proteins
Structural carbohydrates and proteins
Mineral deposits
Fibroblasts
Synthesise fibrous proteins e.g. collagens, elastins and extracellular matrix components (proteoglycans)
Macrophages
Present antigens to stimulate immune cells.
Mast cells
Synthesise histamine and other mediators of inflammation.
Plasma Cells
Synthesise antibodies
Where is loose fibrocollagenous tissue found ?
Around epithelia/ organs
Where is dense fibrocollagenous tissue found ?
Tendons
Ligaments
Types of Fibrocollagenous Tissue
Loose
Dense
Reticular
Where is reticular fibrocollagenous tissue found ?
Liver
Lymph nodes
3 types of Cartilage
Hyaline
Elastic
Fibrocartilage
What does cartilage lack ?
Blood vessels
So exchange of material is via diffusion
How does bone differ from cartilage ?
Bone differs in ECM content. The ECM contains more collagen fibres and the matrix is highly mineralised.
What are the 2 types of fat in adipose tissue ?
White Fat
Brown Fat
Function of White Fat
Energy storage, insulation, protection
Has 1 fat droplet and is the most abundant type of fat.
Function of brown fat
Heat production
Many fat droplets and many mitochondria.
What is adipose tissue ?
A specialised type of connective tissue
