Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
CELL SURFACE JUNCTIONS
(1) Desmosomes (Maculae adherence) - Thickened circular areas on P.M. of adjacent cells with radiating fibrils in cytoplasm. These fibrils called tonofibrils. Desmosomes generally occurs in epithelial cells and provide cell adhesion. Desmosomes without tonofibrils are called terminal bars.
(2) Tight junction or Zona occludence - outer most layers of two P.M. at the site of attachment fuse completely.
Fused membrane reveals a 5- layered structure. Permeability of ions is more at tight junction. Tight junction occurs in nerve tissue at synapses. (electrical synapse)
(3) Gap junction or Nexus - Fine protein channel (connexon) join two P.M of adjacent cells. Exchange of ions between cells may takes place by protein channels. Desmosomes, Tight junction and Gap junction occurs in animal cell.
(4) Plasmodesmata - Name proposed by strassburger. Cytoplasmic connection bet. Two adjacent cells through pores in cell wall and cell membrane. Plasmodesmata are characteristic of multi-cellular plants and they maintain continuity of cytoplasm between adjacent cells. Plasmodesmata often contain an expanded E.R. termed as desmotubule.
. Explain why the traditional classification of unicellular eukaryotes as ‘protozoa’ or ‘protists’ is invalid in terms of modern systematics and evolutionary theory. Why are trad
D i a g no s i s Diagnosis, the key for successful management of the disease problem, refers to identification of the cause of a disease. The process of diagnosis requir
What''s the classification of simple protein?
Q. How are the male gametes and the male gametophytes formed in angiosperms? In the anthers of every stamen there are pollen sacs. Inside the pollen sacs there are microspore m
why obelia is considered to be of special interest in zoology ass an animal showing intermediate grade of organisation
What is Cerebral Hemorrhage Cerebral hemorrhage is a massive bleeding into the substance of the brain. The most frequent cause is high blood pressure, or hypertension. Other ca
Metabolic Events Let us now examine the changes that occur in the seeds after they imbibe water. In general, the most important metabolic events are: Degradation
What are algal blooms
The allele that causes albinism (p) is recessive to the allele for normal pigmentation (P). A normal woman whose father is an albino marries an albino man whose parents are both no
Explain some side effects of carbohydrate loading? Some potential side effects of carbohydrate loading are: Muscle , stiffness Diarrhoea Chest Pain Depres
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd