Transcript Snímek 1

Tissues
of vertabrates
Premedical 22
Tissues = cells of same shape
and the same function
extracellular matrix
1. Epithelia – ectoderm,
mesoderm, endoderm
2. Connective tissue - mesoderm
3. Muscular tissue - mesoderm
4. Nervous tissue - ectoderm
Basement membrane - thin sheet of fibers that underlies
the epithelium, which lines the cavities and surfaces of organs, or the
endothelium, which lines the interior surface of blood vessels
1. By fusion of endothelial and epithelial cells / kidneys and alveoli
two laminae: lamina densa, lamina lucida
2. Epithelial cells with fibrous tissue: lamina densa and
reticularis
http://www.thefullwiki.org/Basement_membrane
1. Epithelia – form from one or more layers of cells
covering an external surface or lining a cavity
http://www.thefullwiki.org/Squamous_epithelium
Single layer of squamous flat cells
Single layer of cuboidal cells (sweat, digested food)
Single layer of columnar cells - may function to absorb substances
Single layer of columnar cells with microvili - help move substances over their surface
Stratified e. of cuboidal cells
Stratified Squamous Epithelium (non-keratinized)
Stratified Squamous Epithelium (keratinized)
Transitional e. with cells range from flat to tall cells
Pseudostratified Ciliated Columnar Epithelial Tissue
Simple squamous epithel (2) - capillary
Simple columnar epithel –
gal gladder
Vesica fellea
Hematoxylin-Eozin
Single layer of columnar cells (2) with microvili
(3)- oviduct
1 - lamina propria, 4 – gland cells
Stratified e. of cuboidal cells with microvilli (2) - trachea
1 - submucosa
Stratified Squamous Epithelium (1) (non-keratinized)
Uterus :2 - submucosa
Stratified Squamous Epithelium (keratinized) – Cutis- Skin
Transitional Epithelium (2) (urinary bladder)
1 – lumen of vesica urinaria, 3 - Lamina propria mucosae
Function of epithelial tissue
• protection and cover - the skin - protect underlying
tissue from mechanical injury, harmful chemicals, invading
bacteria and from excessive loss of water
• sensation - specialized epithelial tissue containing
sensory nerve endings is found in the skin, eyes, ears,
nose and on the tongue
• secretion – glands - epithelial tissue is specialized to
secrete specific chemical substances such as enzymes,
hormones and lubricating fluids
• resorption, absorption - certain epithelial cells
lining the small intestine absorb nutrients from the
digestion of food [lining inside surface of hollow organs]
• respiratory, diffusion - simple epithelium promotes
the diffusion of gases, liquids and nutrients. Because
they form such a thin lining, they are ideal for the
diffusion of gases (eg. walls of capillaries and lungs).
Glands - secretion
Secretion :
merocrine (pancreas) / exocytose
apocrine (lacteal gland)
holocrine (sebaceous gland)
Gland:
•Exocrine
- secrete chemicals into ducts
– outlets
•Endocrine
–without outlets – directly to
body fluids
pancreas
lacteal gland
sebaceous gland
2. Connective tissue
play a central part in the support and repair of almost every
tissue and organ
and the adaptability of their differentiated character is an
important feature of the responses to many types of damage
Collagen is the main protein of connective tissue in
animals, making up about 25% of the total protein content
Proper fibrous tissue
Cartilage
Bone
Embryonic connective tissue
Connective-tissue cells:
Fibroblasts
Cartilage cells (chondrocytes)
Bone cells (osteoblasts and osteocytes)
Fat cells (adipocytes)
Mast cells
Macrophages
Leucocytes
Fiber types as follows:
collagenous fibers
elastic fibers
reticular fibers
Fibroblasts with dark nuclei [A] are seen here
along with thick collagen fibers [B], thin elastic
fibers [C] and very fine reticular fibers [D].
Loose fibrous tissue
- Areolar loosely organized fibers
Fibers are collagenous, but elastic and reticular fibers are
also present, in many serous membranes
- Reticular a network of reticular fibers, made of type III
collagen
- Adipose white, brown
Dense fibrous tissue
Dense regular connective tissue (Ligament, Tendon,
Aponeurosis)
Dense irregular connective tissue (Submucosa, Dermis)
Embryonic connective tissue - mesenchymal
Specialized
Bone
Cartilage
white, brown
adipose tissue
Vertical section of duodenum: 1 - Tunica mucosa, 2 - Tunica submucosa, 3 – Brunner gland
Tendon
Cartilage
– the joints between bones, the rib cage, the ear, the nose,
the elbow, the knee, the ankle, the bronchial tubes and
the intervertebral discs.
• chondrocytes that produce a large amount of ECM
composed of collagen fibers, rich in proteoglycan, and
elastin fibers
• elastic cartilage - epiglottis
• hyaline cartilage
• fibrocartilage
hyaline cartilage
elastic cartilage - epiglottis
1 – elastic cartilage, 2 - perichondrium, 3 – seromucin glands, 4 - Tunica
mucosa
Bone
produce red and white blood cells – red marrow - in long
bones store minerals and fatts (yellow) most notably calcium
and phosphorus (calcium phosphate 2/3, calcium
hydroxyapatit 1/3)
Ossification (or osteogenesis)
Intramembranous ossification is the direct laying down of
bone into the primitive connective tissue (mesenchyme),
while endochondral ossification involves cartilage as a
precursor.
1. periosteum
2. compact bone
3. spongy bone
4. Bone marrow – medulla
• Diaphysis
• Epiphysis
http://doctorsgate.blogspot.com/2010/11/compact-vs-spongy-bones.html
3. Muscular tissue – contractility
upon stimulation
skeletal muscle
long, multinucleated syncytial
cells by fusion of myoblast cells
their nuclei are located peripherally adjacent to the
plasma membrane (sarcolemma).
Controll by our will, spinal (medullary) and cerebral
nerves, cortex
Skeletal and muscles of tongue and pharynx
smooth muscle
composed of sheets or bundles of relatively
short, spindle-shaped cells
not striated, and have a single central
nucleus are interconnected by gap junctions.
Muscles of digestive system, uteri, gall
bladder, dermis,
Controll by autonomic [vegetative] nerves
cardiac muscle
composed of branching and anastomosing chains of
cardiac muscle cells
are joined to their neighbours by intercalated discs,
which contain anchoring and gap junctions.
The anchoring junctions (adherens junctions and
desmosomes) physically connect the cytoskeletons
and contractile apparatuses of the neighboring cells.
Control by autonomic [vegetative] nerves
Muscle - structure
A.Muscle with fascia
e. tendon
f. bundle of fibers
B. Fiber
C. Myofibril from
sarcomers
g. actin
h. myosin
Composed of actin (thin) and myosin (thick)
filaments and associated proteins
is organized into myofibrils
The regular repeating segments (sarcomeres) of
myofibrils give skeletal and cardiac muscle cells
transverse striations. In smooth muscle cells, actin
and myosin filaments form contractile fibers, which
do not appear as highly organized as myofibrils
4. Nervous tissue
composed of cells with long
processes, which may run in
bundles of parallel fibers.
The cells are divided into excitable
cells (called neurons, lead
impulses ) and the more numerous
supporting cells (called neuroglia or
glial cells)
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
neuron
• Centripetal fibers - dendrits
• centrifugal fibers – neurits – axons
neuroglie
Schwann cells - origin of neurolemma which
cohere with
sheath myelin
Nerve
grey and white fibers
with or without
Thank you for your attention
Campbell, Neil A., Reece, Jane
B., Cain Michael L., Jackson,
Robert B., Minorsky, Peter V.,
Biology, Benjamin-Cummings
Publishing Company, 1996 –
2010.