A02 Histology Flashcards
What are the precise terms for active and inactive chromatin, and how do these chromatin structures differ in appearance?
- Active chromatin (euchromatin)
- Inactive chromatin (heterochromatin)
- Euchromatin has a less compactstructure (lesscondensed)than heterochromatin this is because the euchromatin is actively being transcribed
What is the cytoskeleton? What are the main components and main functions?
- Helps maintain shape and internal organisation, provides mechanical support for essential functions such as division. Made up of interlinking protein filaments
What term is commonly used to describe the structure of the plasma membrane of a mammalian cell?
- Phospholipid Bilayer
Why is the vascular/avascular nature of epithelia significant?
- Epithelial tissues are avascular therefore there is no blood supply directly supplying the tissues. They are capable of rapidly replicating or replacing dead or damaged cells with no harm being caused to the body
Histological analysis of biopsy specimens is often used in diagnosing disease. Name a disease where histology is used in routine screening of the population
Cancer
Why is histology important to biomedical science?
- Important for understanding the body and for researching diseases and drug treatment
What are the advantages of using cell lines in research?
Cells can multiple indefinitely
Location of skeletal muscle
Attached to bones
Location of smooth muscle
Internal structures
Location of cardiac muscle
Heart
Tendon tissue type
Connective
pain receptor tissue type
Nervous
enterocytes tissue type
Epithelial
adipose tissue type
Connective
Biceps femoris tissue type
Muscle
femur tissue type
Connective
spinal chord tissue type
Nervous
Thyroid gland tissue type
Epithelial
Olfactory receptor cells tissue type
Nervous
Cardiac myocytes tissue type
Muscle
What is epithelial tissue
- epithelia cover body surfaces, line the body cavity and form glands.
- Can be single layered or multiple layered
- Very close association with each other due to specialised cell junctions
- Can form sheets of cells
- Communicate with exterior of body
- Create a barrier between the host and the ‘free surface’ e.g. skin, digestive tract or saliva
What is connective tissue
- These tissues underlie epithelia and support and surround other basic tissue types.
- This tissue is also known as ‘Support Tissue’ as it provides metabolic and physical support to other tissues.
- Clearly separated from each other
- Spaces between them is occupied by the extracellular matrix produced by connective tissue cells
- Nature of the cells and the extracellular material they produce varies according to function
What is muscle tissue
- Composed of aggregations of contractile cells responsible for the movement of the body and its parts.
- Provide sufficient contractile activity that they are able to move an entire organ or organism
- Large amounts of contractile proteins in their cytoplasm
- Aggregated into distinct bundles allowing them to optimise the movement they generate
What is nervous tissue
- Gather, transmit, integrate information from the body and its external environment, process it, provide a memory and/or reaction and control the muscular and glandular activity of the body.
- Highly specialised to transmit electrical impulses rapidly and accurately from one site of the body to another
- Electrical properties
- Integrate these electrical impulses
- Each neurone has a cell body from which extends a single axon which is usually long and has numerous dendrites
- Dendrites conduct the impulses into the cell body
- Axons propagate the stimulus away from the neurone cell body
