2025年3月2日 · The chicken (taxon -Gallus gallus) embryo develops and hatches in 20 to 21 days and has been extensively used in embryology studies. Historically, the chicken embryo was one of the first embryos studied, readily available and easy to incubate, embryo development can be directly observed by cutting a small window in the egg shell.

cross section of 48 hour chick embryo through trunk region and lateral body fold

Only the head region lifts up above the area pellucida. In this preparation, one can see the chorda (notochord) in the region of the anterior intestinal portal. This structure marks the differentiating foregut which is formed as a blind pocket bordered by endodermal tissue.

5 天之前 · This anterior region which projects, free from the blastoderm, may now properly be termed the head of the embryo. The space formed between the head and the blastoderm is called the subcephaUc pocket (Fig. 17, E).

In the embryo stage around 20 hours after fertilization, the head fold is visible as a half circle that lifts up from the subcephalic pocket in the front of the germ layer. The proamnion lies in front of (= pro) this head fold as a clear zone. The amnion is one of the membranes that will protect the embryo in a later stage.

This page on the embryology in chicken relates to the following: Whole mount preparation 72 hours, with a detail view on the development of the head ( More... Cross sections 72 hours; eye and heart formation ( More...

This document provides a series of summaries of sections through a 24-hour chick embryo and a 33-hour chick embryo. The sections show development of structures like the neural tube, notochord, somites, heart, and gut.

Formation of the head fold (HF) is the first step in this cascading sequence of out-of-plane tissue folds. The HF establishes the anterior extent of the embryo and initiates heart, foregut and brain development. Here, we use a combination of computational modeling and experiments to determine the physical forces that drive HF formation.

Sagittal Sections of an E10.5 Stage 36 Chick Embryo. This atlas depicts sagittal sections through the developing brain and head of a Hamburger and Hamilton stage 36 (Embryonic day 10.5 or E10.5) white leghorn chick embryo. The work was carried out under ethical approval from the University of New South Wales Animal Ethical Committee.

The document describes the development of a chick embryo over 48, 72, and 96 hours of incubation through diagrams, descriptions, and characteristics. At 48 hours, the head has undergone torsion and flexion. At 72 hours, structures like the optic cup and lens are visible.