01:119:116 Lecture Notes - Lecture 5: Hox Gene, Blastomere, Archenteron

• School: Rutgers University
• Department: Biological Science
• Course: 01:119:116
• Professor: Gregory Transue

Document Summary

All with differentiated (specialized cells) with specific functions. Most animals with differentiated tissue->groups of cells with common structure and function as unit. Fertilization->small, flagellated sperm cell (n) which fertilizes large, non-motile egg (n); n+n->2n zygote. 1. endoderm: inner layer of embryonic tissue: ectoderm: outer layer of embryonic tissue, archenteron: pouch formed during gastrulation. Cleavage: series of mitotic divisions without cell growth between divisions. Blastula: hollow ball of cells that surrounds cavity called blastocoel. Gastralation: embryo fold inward and expands filling blastocoel and producing gastrula-structure with different layers of embryonic tissue. Other animals with at least one larval stage. Eats different food, live in different habitat than adults. Undergo metamorphosis: development to juvenile (sexually immature) then development to adult. Homeobox genes: code for proteins that regulate expression of developmental genes. Ex: hox genes: important in animal embryo development. Do not have clearly defined tissues and organs. Symmetry: arrangement of body structures in relation to particular axis of body.