- •II. Фаза роста
- •III. Фаза созревания
- •Iy. Фаза формирования (спермиогенез)
- •I. Фаза размножения
- •II. Фаза роста
- •III. Фаза созревания
- •Основные различия процессов сперматогенеза и овогенеза
- •Оплодотворение
- •Биологическое значение оплодотворения
- •Типы яйцеклеток
- •Эмбриональное развитие птиц
- •Эмбриональное развитие человека
- •Желточный мешок
- •Аллантоис
- •Плацента
- •Дифференцировка зародышевых листков
- •Gametogenesis. Reproductive cells
- •Spermatogenesis
- •Oogenesis
- •Ovary Structure
- •Fertilization
- •Biological significance of fertilization
- •Comparative Vertebrate Embryology classification of egg cells
- •Tabl.2 types of oocytes
- •A) primary isolecithal egg cell; b) mesolecithal egg cell; d) pronounced telolecithal egg cell; e) secondary isolecithal egg cell:
- •1) Nucleus; 2) yolk (vitelline) granules; 3) follicular cells
- •Cleavage
- •Tabl.3 The principal types of cleavage and blastula
- •Gastrulation
- •Invagination;
- •Immigration.
- •The embryonic development in birds
- •Fig.17. The diskoblastula in the chick (the vertical section).
- •1) The germ disk; 2) epiblast; 3) hypoblast; 4) yolk
- •Extra-embryonic (provisory) organs
- •17) Aorta; 18) forming gut tube; 19) coelom; 20) blood vessels in the yolk sac wall.
- •Fig.23. Formation of extraembryonic organs in Birds early stages of human embryogenesis
- •The first week of life. Fertilization to implantation period
- •The second week of life. Bilaminar period.
- •The third week of life. Trilaminar and embryonic shield period
- •Extra-embryonic membranes and provisory organs
- •Differentiation of the Germ Layers
- •Fig.10 Gastrulation and differentiation of the germ layers in human
Fig.10 Gastrulation and differentiation of the germ layers in human
A – the germ disk (15 days);
B – stage of the primitive streak;
C – migration of cells of mesoderm and notochord (17-18 days);
D – trilaminar embryo;
E – neurulation and differentiation of mesoderm (20-21 days)
1 – the primitive node; 2 – the primitive streak; 3 – extra-embryonic mesoderm;
4 – the amnion wall; 5 – the yolk sac wall; 6 – epiblast; 7 – hypoblast; 8 - cloacal membrane; 9 – prechordal plate; 10 epidermal ectoderm; 11 – neuroectoderm;
12 – intraembryonal mesoderm; 13 – entoderm; 14 – notochord; 15 – neural tube’ primordium; 16 – somite; 17 – intermediate mesoderm (nephrotomes);
18 – parietal mesoderm; 19 – visceral mesoderm
Table 7
Derivatives of the nerve crest |
Sensory neurons of spinal ganglia and ganglia of cranial nerves; Neurons of the sympathetic and parasympathetic nerve system; Schwann cells and cells-satellites of ganglia; Neurohypophysis (posterior pituitary gland); Pia mater and arachnoid membrane Melanocytes; Cells of the carotoid body; Calcitonin-producing cells (parafollicular cells) of the thyroid gland; Chromaffine cells (the adrenal gland) Cartilage, bones, muscles and connective tissue of the face; Maxillary and mandibular processes; Sublingual arches and the 3-d throat arch; Odontoblasts; Corneal endothelium Dilator and sphincter pupillae muscles Ciliary muscle |