Fibroblasts (active form) and fibrocytes (quiescent mature form) are the most abundant and ubiquitous resident cells of proper connective tissue throughout the animal body. They synthesize the extracellular matrix components including collagen, elastin, reticular fibers, and ground substance glycosaminoglycans.

Option breakdown:

• Reticular cells are specialized stromal cells restricted mainly to lymphoid and hematopoietic organs.
• Macrophages are phagocytic immune cells scattered in variable numbers in tissues.
• Fibrocytes/fibroblasts are the primary, most numerous cell type of mature connective tissue.
• Mesenchymal cells are multipotent embryonic precursor cells.

In the avian egg, the yellow yolk is stratified around a flask-shaped core of light-colored, protein-rich white yolk called the Latebra.

• The Latebra forms a central cavity of white yolk.
• narrow tube of white yolk extends from the latebra upward to the animal pole, terminating beneath the blastodisc in an expanded disc termed the Nucleus of Pander.
• The entire flask-shaped white yolk column is known as the latebra.
  
  Option breakdown:
• Blastoderm is the cellular embryonic disc developing from the zygote after fertilization.
• Chalazae are twisted protein cords anchoring the yolk in the center of the albumen.
• Latebra is the flask-shaped white yolk core extending to the yolk center.
• Nucleus of Pander is the flared sub-germinal apex of the neck of the latebra.

Ceruminous glands are specialized modified sweat glands situated in the external acoustic meatus of the ear. Morphologically, they are simple coiled tubular glands (A), and functionally their mode of secretion is apocrine (B), releasing earwax (cerumen) in combination with sebaceous secretions. Sebaceous glands are holocrine, not ceruminous glands.

Option analysis:

• Statement A: True. Ceruminous glands exhibit a simple coiled tubular architecture.
• Statement B: True. Their secretory mechanism is apocrine.
• Statement C: False. They are unbranched coiled tubular, not branched tubular.
• Statement D: False. Sebaceous glands are holocrine; ceruminous glands are apocrine.

Globule leukocytes (also referred to as intraepithelial granulated lymphocytes) are unique immune cells found in mucosal epithelia, especially the respiratory, digestive, and urinary tracts of parasitized or inflamed animals. Ultrastructural, immunohistochemical, and developmental studies confirm that globule leukocytes represent a specialized subpopulation of mucosal intraepithelial T lymphocytes (specifically cytotoxic T cells or mucosal mast cell lineage closely aligned with T lymphocytes).

Option analysis:

• T lymphocyte: Correct. Recognized as intraepithelial T cell derivatives characterized by large acidophilic cytoplasmic globules.
• Lymphocyte: Incorrect. B cells mature into antibody-secreting plasma cells, not globule leukocytes.
• Eosinophils: Incorrect. Granulocytes of myeloid lineage; globule leukocytes were historically confused with them but are lymphoid.
• Neutrophils: Incorrect. Polymorphonuclear granulocytes mediating acute phagocytic inflammation.