What is Perivitelline membrane?

Anatomical terminology. The vitelline membrane or vitelline envelope is a structure surrounding the outer surface of the plasma membrane of an ovum (the oolemma) or, in some animals (e.g., birds), the extracellular yolk and the oolemma.

What is the function of perivitelline space in ovum?

The perivitelline space is the space between the zona pellucida and the cell membrane of an oocyte or fertilized ovum. In the slow block to polyspermy, the cortical granules released from the ovum are deposited in the perivitelline space.

What is perivitelline space Class 12?

4)Perivitelline space- The space found between the zona pellucida and the cell membrane of an oocyte is called the- perivitelline space.

What does zona pellucida mean?

Zona pellucida: The strong membrane that forms around an ovum as it develops in the ovary. The membrane remains in place during the egg’s travel through the fallopian tube. To fertilize the egg, a sperm must penetrate the thinning zona pellucida.

What does perivitelline stand for in medical dictionary?

peri·​vi·​tel·​line space | \\ ˌper-ə-vī-ˈtel-ən-, -ˌēn-, -ˌīn- \\. : the fluid-filled space between the fertilization membrane and the ovum after the entry of a sperm into the egg.

What makes up the perivitelline fluid in the egg?

To cope with that embryos are surrounded by a perivitelline fluid (PVF) that nourishes and protects them, mainly composed of polysaccharides and proteins (perivitellins) ( Garín, Heras & Pollero, 1996; Giglio et al., 2016; Hayes et al., 2015; Heras, Garín & Pollero, 1998; Heras et al., 2007 ).

Which is the second most abundant component of perivitelline fluid?

Proteins, called perivitellins, are the second most abundant component of the perivitelline fluid. Perivitellins are also a source of nutrients for snail embryos and play a role in protection against pathogens and predators, and include non-digestible perivitellins, toxins and protease inhibitors.

Which is the outermost membrane of the perivitelline?

The outermost membrane, the chorion, overlays the viscous fluid-filled perivitelline space, the vitelline membrane, and the blastoderm (or embryo) and yolk (Jones et al., 1978; Rawson et al., 2000).