Lab 2: The Tissues Flashcards
What is a tissue? Not the kleenex kind…
A group of cells w/ similar structure and function plus extracellular substances located between cells.
What the name of the microscopic study of tissues?
Histology
What are the five basic tissue types?
Connective, blood, epithelial, muscle, nervous.
What are the two major constituents of connective tissue?
Cells and extracellular material.
What is the function of the extracellular material and what does it consist of?
Determines the physical properties of each type of connective tissue. Consists of a matrix of inorganic material called ground substances and within which are imbedded a variety of fibres.
What are the two types of cells found in connective tissue?
Fibroblasts and adipocytes.
What is the function of fibroblasts?
synthesis and maintenance of extracellular material
What is the function of adipocytes?
storage and metabolism of fat
What is the ground substance and its main components?
Amorphous material which have consistency of semi-fluid gel. Bounds tissue fluid, medium for material passing throughout CT, exchange of metabolites w/ circulatory system.
Components: glycosaminoglycans, proteoglycans (which bind to each other to form long chains, water, and positive ions (sodium)).
What are the three main types of fibres that make up CT?
Collagen (most abundant protein in body), elastin (arranged as fibres, sheets), and structural glycoproteins (group of fibre forming molecules including fibronectin and laminin, associated w/ cell surface membranes.)
What is blood?
A connective tissue made up of cells in plasma, exchanged w/ extracellular fluid medium of all tissues.
What are the three types of functional classes of blood cells?
Erythrocytes, leukocytes, thrombocytes (platelets).
What is the function of erythrocytes?
Involved in oxygen and carbon dioxide transport.
What is the function of leukocytes?
Defense and immune systems of body
What is the function of thrombocytes?
Clotting!
What is plasma?
Aqueous solution of inorganic salts and proteins which is constantly being component of blood clotting.
Where are cell types formed and what is the process called?
Bone marrow, hematopoiesis.
What is the function of epithelia?
Lining all body surfaces, cavities, tubes - interfaces between biological components.
What are epithelia supported by?
A basement membrane of variable thickness.
Function of basement membranes?
Separate epithelia from underlying CT and are never penetrated by blood vessels; therefore epithelia are dependent on diffusion of oxygen and metabolites from underlying tissues.
What are the three morphological characteristics that classify epithelia?
1) Number of cell layers (simple vs. stratified)
2) Shape of cells (squamous, columnar, etc,)
3) Presence of surface specializations. (eg cilia, keratin)
What are the three types of muscle?
Skeletal, smooth, cardiac
Features and function of skeletal muscle?
Voluntary, striated, multi-nucleated, all or none fashion. Movement of skeleton and organs (eg globe of eye and tongue).
Features and function of smooth muscle?
Involuntary, mono-nucleated, not striated. Muscular component of visceral structures (eg blood vessels, digestive tract, uterus, bladder.) Under inherent, automatic, hormonal control.
Features and function of cardiac muscle?
Involuntary, striated, mono-nucleated, fast all or none fashion - intercalated structure. Continuous, rhythmic contractility of heart.
What are the striations in some muscles?
Contractile proteins that are arranged to make prominent cross striations that appear in histological preparations.
What is the nervous system composed of?
Variation in arrangement of neurons and their supporting tissues. Neurons constitute most sensory receptors, conducting pathways, sites of integration and analysis.
Parts of microscope? Here’s five…
Eyepiece w/ lens, objective lens, arm, focus knobs, base w/ light source.
General function of connective tissue?
To support and “connect” body parts and to protect body from bacteria.
What are the three kinds of CT?
Structural, defensive, sequestering.
3 arrangements of CT?
Dense regular CT - connect bones and muscles
Dense irregular - thick layer of skin
Areolar - flexible
What are the structural elements of the skin which are responsible for its physiological functions?
Stratified squamous epithelial tissue (lines outside) and dense irregular tissue CT (underneath dermis). Function: forming protective layer to body.
What are the three types of cartilage? Differentiate between them
1) Hyaline - reduces friction in joints and at ends of long bones.
2) Elastic - in external ear, consists of cartilage and elastic fibres.
3) Fibrocartilage - mix of cartilage and collagen (protein in CT).
What is the extracellular matrix and how is it produced/maintained?
Aka ground substance. Consists of glycosaminoglycans and proteoglycans. Chondrocytes, which make up cartilage, secrete and degrade matrix when necessary.
Histological structure of bone?
Have harvesian canals, which allow nerves and blood to flow through. They are surrounded by lamellae, which in turn are surrounded by spongy and compact bone.
What is the difference between spongy and compact bone?
Spongy bone has pores, Compact is denser w/ collagen fibres.
Three cell types found in bone and their functions?
1) Osteoclasts - dissolve bones
2) Osteoblasts - form new bones
3) Osteocytes - regulate calcium levels in bloodstream.
6 types of connective tissue covered in lab?
Dense regular, dense irregular, areolar, reticular, elastic, adipose.
8 types of epithelium covered in lab?
1) Simple squamous
2) Stratified squamous
3) Stratified squamous keratinising
4) Simple cuboidal
5) Simple columnar
6) Simple columnar ciliated
7) Pseudostratified columnar
8) Transitional
3 types of muscle tissue covered in lab?
Skeletal, smooth, cardiac plus their cross sections.
2 nervous tissues covered in lab PPT slides?
Motor end plates, peripheral nerve.
