What is the third layer that forms as a result of gastrulation in some animals? mesoderm endoderm ectoderm three layers never form during gastrulation in any animal

Number these steps in vertebrate embryogenesis in order.      ______  formation of archenteron      ______  formation of blastula      ______  neurulation      ______  gastrulation      ______  cleavage       ______  zygote

Which of the following statements is false? a. Cadherins, but not integrins play a role in gastrulation. b. Gastrulation creates the primary germ layers c. Gastrulation requires cells to change their gene expression. d. Body axes are stabilized (made permanent) during gastrulation.

What is the importance of blastopore formation in protostomes? There may be multiple correct answers. Select one or more: O it is involved in the process of gastrulation to form the third layer of tissues in triploblastic organisms: the mesoderm O it is involved in the process of gastrulation, and will be used to release gases from the internal body of an organism O that the gastrovascular cavity of protostomes is formed by the indentation of the blastula early in development, starting with the mouth O that the gastrovascular cavity of protostomes is formed by the indentation of the blastula early in development, starting with the anus O the blastopore isn't really that important

What critical developmental process/es are altered following retinoic acid-exposure, which may cause protrusion of the spinal cord through the vertebral arches? Select one or more: O A. Primary neurulation, where the neural plate creases inward until the edges come in contact and fuse. O B. Secondary neurulation, where the tube forms by hollowing out of the interior of a solid precursor. O C. Regulation of neural crest migration from the neural tube to generate segmental ganglia. O D. Abnormal somite formation affecting the development of muscles of the back.

Tabulate all the differences between frog and mammalian ovaries, frog and mammalian oogenesis

Vertebrate Fertilized Class Blastula or Blastocyst Late Morula Gastrula Egg Embryo Amphibian Reptile Mammal How long after ovulation does it take an embryo to develop? The resulting embryo may become the (attached) in the lining of After eight weeks of development the embryo is called the How long does it takes the fetus to develop and grow inside the mother? What is differentiation? The embryo continues dividing and form all the tissues organs and organ systems of the animal When should pregnant mother take most precaution?

in mammals, the luteinizing hormone has what impact on gamete development? select all that apply. Praiates ovulation Decreases sperm production Increases testosterone levels Stimulates the hypothalamus

Give Detailed Solution (no need Handwritten)

In Ascaris, meiosis and oocyte maturation occur at the same time. Describe the stages that oocytes go through as they pass from the ovaries to the uterus in these worms.