<span>Embryonic tissues or germ layers develop during the gastrulation stage.</span> <span>Gastrulation is a process in embryonic development during which the single-layered blastula is reorganized into a three-layered(or two-layered) structure called the gastrula. <span>Two primary germ layers(embryonic tissues) are an inner layer-endoderm and an outer layer-ectoderm. Endoderm and ectoderm interact and produce a third layer-mesoderm. Gastrulation is followed by organogenesis, three germ layers will give rise to specific tissue and organ.For example, ectoderm gives rise to epidermis and nervous system, endoderm to the digestive system and mesoderm to muscles, bones…</span></span>
Answer:
The best answer is R group. An R - group is a chemical group or side chain that is found attached to the central carbon in amino acids
Explanation:
Answer: The blanks can be correctly filled up with prophase I and metaphase II.
Explanation:
In females, finite number of oocytes are present since birth. The process of oogenesis initiate in embryonic stage only. However, oogonia divide and mature to form primary oocytes. These primary oocytes start meiotic division but arrest in prophase I stage before birth.
After a girl attains puberty, one primary oocyte resumes its division each month during a menstrual cycle. The primary oocyte divides to form secondary oocyte and polar body.
Polar bodies degenerate after completing meiosis II. However, secondary oocyte halts its division again at metaphase II until fertilization takes place. Once fertilization takes place it completes its meiosis II and results into mature ovum and polar body.
The white blood cell identifies the toxin produced by the pathogen and creates antibodies to fight the pathogen
if placed in a salt soultion it will shrivel and die if placed in just water it will burst