Ferilization and Diferentation

Fertilization

The process of sperm and egg joining to form a zygote.

Acrosome

The cap-like structure on the head of a sperm that releases hydrolytic enzymes.

Polyspermy

Fertilization of an egg by multiple sperm, which is prevented by cortical reaction.

Cortical Reaction

The release of cortical granules that forms a fertilization membrane to block additional sperm.

Syngamy

The fusion of male and female pronuclei that restores the diploid state.

Zygote

The fertilized egg resulting from the fusion of sperm and egg.

Differentiation

The process by which cells become specialized.

Determination

The process in which a cell's fate becomes fixed and irreversible.

Totipotent

The ability of a cell to develop into any cell type or a complete organism.

Cleavage

The series of cell divisions that occurs after fertilization, leading to the formation of a multicellular embryo.

Induction

The process where one group of cells influences the development of neighboring cells.

Cytoplasmic Determinants

Factors in the egg cytoplasm that influence gene expression in the developing embryo.

Indeterminate Development

A type of development where early cells can still form an entire organism.

Determinate Development

A type of development where cell fates are determined early and cannot change.

Maternal Factors

Cytoplasmic components inherited from the mother influencing early embryo development.

Spemann’s Model of Differentiation

A conceptual framework illustrating how cells differentiate based on genome, cytoplasmic differences, and environmental influences.

Nuclear Transplant

An experimental technique that transplants a nucleus from one cell into another.

Gene Expression

The process by which information from a gene is used to synthesize a functional gene product, usually protein.

Environmental Influences

External factors like gravity and light that can affect cell differentiation and development.

Cascade Effect

The process where one signal triggers a chain of developmental events.

Irreversible Changes

Permanent modifications in gene expression that lead to cell differentiation.