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Connective tissue

Drs, as we know plasma cell is a protein synthesis cell so its cytoplasm should be deep in colour "due to the numerous cisternae of rER" and the nucleus should be pale?

The cytoplasm is deep basophilic as you can detect the pale (-ve Golgi image) near the nucleus.
About the nucleus, although it's a protein synthesis cell it contains compact coarse of heterochromatin as the amount of the protein secreted (immunoglobulins) is small in amount.

Dr, how in hyaline cartilage matrix is basophilic however collagen fibers are acidophilic?

Collagen fibers are very fine and cannot be demonstrated by H&E stain, the matrix is basophilic due to the presence of chondroitin sulfate.

Why do chondrocytes contain large amount of glycogen, while chondroblasts don't?

Cartilage is avascular (low oxygen tension) so chondrocytes depend on anaerobic glycolysis, so they contain glycogen granules. Chondroblasts are present in the chondrogenic layer of the perichondrium with continuous supply to oxygen and nutrients, no need to store, on the contrary, chondrocytes are far from the perichondrium, so they form their store to maintain their viability and functions

Why there is no perichondrium in the articular surface?

The free surface of articular cartilage is not covered by perichondrium to minimize friction inside the joint.

I can't imagine the types of cartilage growth.

Appositional growth

Interstitial growth

What is Osteoid?

Decalcified bone matrix or organic component of the bone matrix.

Why is there cell nest in cartilage and not in bone?

Chondrocytes can divide while osteocytes cannot.

Dr plz ,, why does grinding method of preparation of bone not used for preparation of spongy bone?

Spongy bone is fragile. It would be destroyed, if this method is used. 

Why are osteoclasts acidophilic?

These cells contain many mitochondria and lysosomes. Also,they pump protons (hydrongen ions) and chloride ions to the extra cellular space, this also may share in the acidophilia of the cytoplasm.

Dr, I cannot imagine "Howship's lacuna".

This is a picture of an osteoclast sitting in a 'Howship's lacuna' in the endosteum. These recesses are areas of bone that the osteoclasts have eroded away. Can you identify the osteolcast, and its 'ruffled border' which is full of fine finger like projections that insert into the bone matrix.