Muscle, connective and nervous tissue Flashcards
Most abundant tissue type in the human body?
Connective tissue
Basic structure of a connective tissue
It contains different types of cells scattered in the large space of extra-cellular matrix which contains fibers.
Extracellular matrix can be solid, liquid or semi-solid.
Type of cells found in the matrix
Fibroblasts (secrete fiber protein)
Macrophages (engulf foreign particles or any debris by phagocytosis)
Mast cells (secrete histamine and heparin)
Fat cells (storage and insulation)
leukocytes (protection)
Different types of fibers found in the matrix
Collagen (provides strength and support)
Reticular fibers (connects connective tissues with other tissues)
elastic fibers (provides elasticity)
Functions of connective tissues
Binding and structural support
Protection
Transport of materials
Insulation
Main types of connective tissues and their examples
Loose connective tissue (areolar and adipose)
Dense connective tissue (fibrous connective tissue)
Skeletal connective tissue (bone and cartilage)
Fluid connective tissue (blood and lymph)
Most abundant form of connective tissue
Areolar tissue
Loose connective tissue (Areolar Tissue)
Most widely distributed connective tissue type in the vertebrate body.
Can be considered as the generalized type of connective tissue.
Types of cells in this tissue are fibroblasts, macrophages, mast cells, leukocytes and fat cells.
All three types of fibres are found in this tissue.
Fibers are loosely arranged and wavy in nature. This tissue binds epithelia and the underlying tissue. Therefore this holds organs in place. This tissue is found under the skin and throughout the body
Fibrous connective tissue( Dense connective tissue)
Contains densly packed fibers and few cells (fibrocytes)
Found in palces where tensile strength is required.
e.g: tendon(connects muscle to bone), ligaments (connects bones at joints) and in the sclera (outer layer of the eye ball) of eye.
Adipose tissue
Specialized cell of loose connective tissue. Each cell contains a large fat droplet. Found underneath the skin and involoves in insulation and stores fuel as fat molecules.
Blood tissue
Blood tissue is a special type of connective tissue where the matrix is not secreted by cells and fibres are only formes during blood clotting process.
Matrix is a fluid known as plasma which contains water, salt and dissolved proteins.
Red blood cells(transports respiratory gases), white blood cells(protection), platelets(blood clotting) are suspended within the matrix.
Largest cel type in blood
Monocytes
Main functions of blood tissue
Transport of materials, protection and osmoregulation.
Cartilage
Matrix is composed of chondroitin sulfate which is a rubbery protein-carbohydrate complex. Chondrocytes and collagen fibers are suspended within the matrix. Chondrocytes secrete chondroitin sulfate and collagen.
Found in places where strength and flexibility is needed such as in trachea and intervertebral discs.
Bone
It is a mineralized connective tissue made up of collagen fibers and inorganic salts such as magnesium, calcium and phosphate. Cells are osteocytes and osteoblasts. osteoblasts are bone forming cells while osteocytes are mature cells. Has repeating units called osteons. At the centre of the osteon contains a canal of blood vessels and nerves.
2 types of bone tissues
Hard bone (has repeating units known as osteons)
Spongy bone ( contains lot of spaces filled with red bone marrow)
3 types of cells in bones
Osteocytes (mature cells maintaining bone tissue)
Osteoblasts (bone forming cells)
Osteoclasts (digestion of old bone tissue)
3 types of muscle tissue
Smooth muscles
Skeletal muscles
Cardiac muscles
Smooth muscle tissue
cells are spindle shaped, uni-nucleated and lacks striations.
This tissue is responsible for involuntary movements such as churning of stomach and constrictions in alveoli.
Found in digestive tract, urinary bladder and arteries.
Skeletal muscle tissue
Contains bundles of long cells with multi-nuclei.
Striations are present with contractile units known as sarcomeres. Undergoes voluntary movements and are connected to the skeletal system.
Contractile units of skeletal muscle tissue
Sarcomeres
Cardiac muscle tissue
Composed of uninucleated cells which are interconnected via intercalated discs. Cells are striated with sarcomeres. Performs involuntary contractions and is only found in the wall of the heart.
Nervous tissue is composed of?
Composed of neurones and neuroglia.
Neurones receive, process and transmits nerve impulses. Glial cells support neurones.
3 types of neurons according to structure
Pseudo-unipolar
Bipolar
Multipolar
What are structural and functional units of the nervous system
Neuron is the structural unit while the functional unit is the reflex arc.
Neuron
Basic structure of the neuron contains cell body, dendrites and axon. Dendrites and cell body receive nerve impulses while axon transmits it.
3 types of neurones
motor
sensory
inter
Types of nerves based on the origin
Cranial nerves (12 pairs originated from the brain)
Spinal nerves (31 pairs originated from the spinal cord)
Glial cells
supportive cells
functions include providing nourishment to neurones and sometime undergoing neuron functions.
Most abundant type of nerve cell?
Neuroglia
Main structural components of connective tissues
Matrix, cells and fibres
Tendons and ligaments
Ligaments attach one bone to another. Tendons attach a muscle to a bone
Largest cell type in blood
Monocytes
Function of intercalated discs
Relays signals from cell to cell and synchronize heart contractions
