Structural Organisation in Animals 2 Flashcards
what is the origin of connective tissue
Origin- Mesodermal
what is matrix of connective tissue
Also known as Ground substance and is composed of
mucopolysaccharide (modified polysaccharide) present in
the form of Hyaluronic Acid.
cells present in connective tissue
(i) fibroblast cells
(ii) mast cells
(iii) macrophage
(iv)
what are fibroblast cells and what is their function
- Largest cells of connective tissue and most maximum in number
- Irregular in shape due to long cytoplasmic processes.
- Cytoplasm is rich in rough ER (producing protein fibres)
- Primary function is to produce protein fibres.
Secrete most of the matrix of Connective Tissue
(Chief matrix producing cell).
what are macrophages
2nd largest in size
* 2nd maximum in number
Amoeboid cells, with
Kidney Shaped Nucleus
*Cytoplasm is agranular but appears to be granular due
to more number of lysosomes
* Phagocytic in nature. Destroy microbes by phagocytosis
*Also called scavengers of connective tissue because they
destroy dead or damaged cells to clean connective tissue
what are mast cells
Small and amoeboid cells
with S-shaped nucleus.
Secrete histamine, serotonin & heparin.
Secrete small amount of matrix in connective tissue.
Histamine - amino acid derivative, vasodilator,
inflammation
Serotonin - amino acid derivative, vasoconstrictor
Heparin- mucoploysaccharide, natural anticoagulant
what are types of fat cells
(i) Monolocular Adipocyte
* Forms White fat
* Single, large, central fat globule is present.
* Cytoplasm and nucleus becomes peripheral.
(ii)Multilocular - Adipocyte
* Forms Brown fat
*Many, small, fat granules distributed in cytoplasm around
nucleus
* Cytoplasm is more
what are lymphocytes
Centrally located large nucleus and hence cytoplasm
becomes peripheral.
Key cell of immune system and is involved in production of
antibodies
it has clear cytoplasm
what are plasma cells
Small amoeboid cells
* In these cells rounded nucleus is present in which chromatin
material is arranged like spokes (radial rows) in wheels so they are
called as cart wheel cells
* Also called clones of lymphocytes as these are formed by division of
lymphocytes
Produce and transport antibodies
what is collagen fibres
▪ Made up of collagen protein
(Most abundant protein in animal kingdom)
▪Wavy, unbranched, inelastic, tough fibres
arranged in bundles (fascia)
▪ On boiling they yield gelatin
what is elastic fibres
▪ Composed of elastin protein
▪ Branched but arranged singly
▪ Maximum elasticity is present
▪ Highly resistant to chemicals
▪ On boiling they do not yield gelatin
what are reticular fibres
Composed of reticulin protein
▪Highly branched fibres which always form dense network
▪Delicate fibres, elasticity absent
▪Mainly found in lymphoid organs such as spleen, lymph
nodes etc.
describe areolar connective tissue
▪ Also known as Spongy Connective Tissue.
▪ It is most widely distributed tissue in the body.
▪ Maximum intercellular space and matrix is present.
▪Due to irregular arrangement of bundle of collagen fibres many
gaps are present. These gaps are called areolae.
▪ In areolae other component of connective tissue like fibres, cells
& matrix are distributed. Few elastic fibres are present.
▪ Fibroblast cells, macrophages and mast cell are more in number.
▪ Function: it serve as a support framework for epithelium.
where is areolar tissue found
-tela subcutanea: tissue connecting skin and unerlying tissue
- submucosa of trachea,bronchi,oesophagus and stomach,inestine
-endomysium and perimysium of muscle tissue
- joins integument with muscles
what is adipose tissue
Another type of loose connective tissue located mainly
beneath the skin.
▪ It contain adipocytes / fat cells abundantly.
▪ The cells of this tissue are specialized to store fats the excess
of nutrients which are not used immediately are converted
into fats and are stored in this tissue.
-fibroplasts store fats in adipose tissue
where is brown fat found
Cold resistance in new born baby is due to
presence of brown fat.
Hibernating animals Like Rat, Shrew