Lecture 15- Tissues of the Human Body

Pregunta	Respuesta
What is the apical surface of the epithelium?	The surface exposed to a body cavity, lining an organ or exposed to an exterior and can contain microvilli or cilia.
What is the basal surface of the epithelium?	The surface attached to a basement membrane secreted by the cells and adheres the tissue firmly to nearby connective tissue.
What are the different types of epithelial tissue layers called?	Simple epithelium, stratified epithelium and pseudostratified epithelium
What is the structure of simple epithelium?	Single layer allowing diffusion, osmosis, filtration, secretion and absorption to take place
What is the structure of stratified epithelium?	Multiple layers of cells, protecting deeper layers from wear and tear.
What is the structure of pseudostratified epithelium?	Single layer of cells that appear to consist of multiple layers as they have nuclei at different levels.
What are the different epithelial cell shapes?	Squamous, cuboidal, columnar and transitional
What are squamous epithelial cells?	Flat cells with oval nuclei
What are cuboidal epithelial cells?	Cube like cells with a central nuclei
What are columnar epithelial cells?	Column shaped cells with variable nuclei
What are transitional epithelial cells?	Variable shaped cells
How do you classify epithelia?	1: The type of layers (simple, stratified or pseudostratified) 2: The cell shape (squamous, cuboidal, columnar or transitional)
How do you name multilayered epithelia?	Named after top layer
What is simple squamous epithelia adapted for?	Diffusion, osmosis and similar process requiring a minimal barrier
Where is simple squamous epithelia found?	It lines the capillaries and blood vessels, lymph vessels and alveoli
What is simple cuboidal epithelia adapted for?	Absorption, secretion and protection
Where is simple cuboidal epithelia found?	It lines parts of the kidney tubules, ducts of many glands and part of the ovary.
What are non-ciliated simple columnar epithelia adapted for?	Adapted for absorption and secretion
What can non-ciliated simple columnar epithelia contain?	Microvilli and goblet cells that produce mucus
Where can non-ciliated simple columnar epithelial be found?	Lines the digestive tract, gallbladder and large ducts of glands
What are ciliated simple columnar epithelia adapted for?	The movement of substances across the epithelial surfaces
What do ciliated simple columnar epithelia possess?	Apical cilia
Where can ciliated epithelia be found?	Uterus, bronchi and paranasal sinuses
Do non ciliated pseudostratified columnar epithelia contain goblet cells?	No
Can ciliated pseudostratified columnar epithelia contain goblet cells?	Yes they can
Where can non-ciliated pseudostratified columnar epithelia be found?	It is rare but it is found in parts of the male urethra
Where can ciliated pseudostratified columnar epithelia be found?	Line most of the trachea, primary bronchi, parts of the male reproductive and urinary tract, nasal cavity and large excretory ducts
What is the role of stratified squamous epithelia?	Protects against abrasion
What are the two different types of stratified squamous epithelia?	Non keratinised and keratinised
Where can non-keratinised stratified squamous epithelia be found?	Lines the mouth, vagina and anus
What are keratinocyte cells?	Cells in which keratin is produced
What is the process of keratinisation?	As the cells traverse the layers, they fill with keratin, become squamous and anucleate and eventually die as they reach top layer
What is desquamation?	The process by which keratinised cells slough off
What is the role of the keratinised layer?	It provides a waterproof barrier, protecting against abrasion and pathogens
What is the role of stratified cuboidal epithelial?	Provides protection
Where is stratified cuboidal epithelia found?	Ducts of sweat glands, larger salivary glands and parts of male urethra
What is the role of stratified columnar epithelia?	Protective
Where is stratified columnar epithelia found?	Salivary glands and male urethra
What is the role transitional epithelia?	Able to stretch
What prevents transitional epithelia from leaking?	Tight junctions
Where is transitional epithelia found?	urinary bladder, ureters and parts of urethra
What is a gland?	A single or group of epithelial cells adapted for secretion
What do exocrine glands do?	Secrete material directly into ducts or onto apical epithelial surface
What are exocrine glands composed of and what do they secrete?	They are composed of glandular epithelia and secrete mucus, sweat, oil, earwax and digestive enzymes
What do endocrine glands do?	"ductless glands'" that secrete materials through the basal surface which diffuses through the basement membrane, connective tissue and into the bloodstream (e.g. hormones)
What are the two structural classifications of exocrine glands?	Unicellular and multicellular glands
What is the structure of unicellular glands?	They have goblet cells but no ducts are involved
What is the structure of multicellular glands?	Usually involves ducts
What are the different classifications of ducts according to their shape?	Image: ducts (image/jpg)
What are the different functional classifications of exocrine glands?	Holocrine, merocrine and apocrine
What are holocrine glands?	Cell accumulates substance for secretion, dies and discharges its contents (oil in sebaceous glands)
What are merocrine glands?	Secretion occurs by exocytosis (sweat glands)
What are apocrine glands?	Small pieces of cell containing secretion break off and cell repairs itself
Name two types of endocrine release?	Paracrine and autocrine
What does paracrine mean?	Neighbouring cells are effected
What does autocrine mean?	The same cell is affected
What is the structure of connective tissue?	Cells are sparsely distributed within extracellular matrix material produced by connective tissue cells (except for blood matrix)
What does the matrix contain?	Fluid, dissolved molecules and protein fibres (e.g. collagen and elastin)
What is the structure of collagen and where is it found?	Thick and strong. Found in tendons.
What is the structure of elastin and where is it found?	Thin and elastic. Found in skin.
What determines the function of connective tissue?	The composition of the matrix
What are the four types of connective tissue?	Connective tissue proper, cartilage, bone and blood
What are the two types of connective tissue proper?	Loose and fibrous/dense
What are the three types of loose tissue?	Areolar (wraps organs), Adipose (fat tissue) and Reticular (supporting framework in liver)
What are the three types of fibrous /dense tissue?	Regular (tendons and ligaments), Irregular (heart valves, around cartilage and muscle) and elastic (lungs, walls of arteries, bronchial tubes)
What is the structure of muscle tissue?	Rich in overlapping protein filaments known as myosin and actin which are responsible for muscle shortening
What is required for muscles to contract?	ATP
What are the three types of muscle tissue?	Skeletal, cardiac and smooth
What type of movement does skeletal muscle perform?	Voluntary
What are skeletal muscle attached to and how are they attached?	They are attached to bones via tendons
What is the appearance of skeletal muscle?	Strained in appearance and consists of long cells with many nuclei
What type of movement does cardiac muscle perform?	Involuntary
What is the appearance of cardiac muscle?	Strained in appearance and consists of branched cells with a single nuclei
What is the role of intercalated disks within cardiac muscle?	They electrically couple cells
What type of movement does smooth muscle perform?	Involuntary
Where is smooth muscle found?	Walls of blood vessels, gastrointestinal tract, uterus and part of the urinary system
What is the appearance of smooth muscle?	Lacks striations and spindle shaped cells with single nuclei
What are the two main components of nervous tissue?	Neurones and glial cells
What is the role of glial cells?	They are protective and supporting

Siguiente

Lecture 15- Tissues of the Human Body

Descripción

Resumen del Recurso

Similar

	Creado por emma_moran hace casi 11 años