The Key Concepts of Developmental Biology: From Zygote to Organism

Don Mariano Marcos Memorial State University - North La Union Campus

Developmental Biology

It is the study of the processes by which organisms grow and develop.

Fertilization

This crucial event forms a single-celled zygote, containing a complete set of chromosomes from both parents.

Sperm-Egg Fusion

A cascade of biochemical reactions.

Genetic Blueprint

Creation of a unique genome.

Activation of Development

Initiating the first cell division.

Cleavage

Rapid mitotic divisions without overall growth, increasing cell number.

Blastulation

Formation of the blastula, a hollow ball with an inner cell mass and outer trophectoderm.

Morula Formation

A solid ball of cells, resembling mulberry.

Early Differentiation

The first distinction between future embryo and placenta cells.

Gastrulation

A pivotal event where the blastula reorganizes into a three-layered structure, defining the primary germ layers that will form all tissues and organs.

Ectoderm

gives rise to skin, nervous system, and sensory organs

Mesoderm

gives rise to muscle, bones, circulatory system, and kidneys

Endoderm

gives rise to digestive tract lining, lungs, liver

Organogenesis

It is the process where germ layers differentiate into specific organs and organ systems.

Pattern Formation

it ensures that organs develop in the correct locations and orientations

Inductive Interactions

cells influencing the fate of neighboring cells

hox genes

master control genes that regulate body plan organization

apoptosis

programmed cell death for sculpting tissues and organs

Cellular differentiation

it is the process by which cells become specialized, acquiring unique structures and functions.

Stem cells

have remarkable ability to self-renew and differentiate, are at the heart of this process.

Totipotency

can form a complete organism

pluripotency

can form any cell type in the body

multipotency

can form multiple cell types within a lineage

growth factors

proteins that stimulate cell growth and differentiation

transcription factors

proteins that control gene expression

epigenetics

heritable changes in gene expression without altering DNA sequence

Trisomy 21

Down Syndrome