Question

The embryos of complex multicellular animals must establish spatial coordinates in order for development to proceed. an important reference coordinate for developing frogs is the (a) location of the vegetal pole. (b) location of the animal pole. (c) point of sperm penetration. (d) location where gastrulation begins. (e) direction of the sun.

Answer 1

The embryos of complex multicellular animals must establish spatial coordinates in order for development to proceed. an important reference coordinate for developing frogs is the  point of sperm penetration, in the region the animal pole, in the male frog, the two testicles are attached to the kidneys and the semen passes to the kidneys through thin tubes called efferent ducts, then it travels through the ureters, which are known as urinogenital canals. There is no penis, and the sperm is expelled from the cloaca directly onto the eggs when the female lays them. The ovaries of the female frog are next to the kidneys and the eggs go through a pair of oviducts and through the cloaca to the outside.

Answer 2

The embryos of complex multicellular animals must establish spatial coordinates in order for development to proceed. On that note an important reference coordinate for developing frogs is the point of sperm penetration into the egg.

Answer: Option C

Explanation:

Sperm is an amphibian that reproduces sexually, the point of penetration of the frog sperm into the egg causes the centrosomes of the sperm to act at right angles to the direction of the sperm path, this pushes the sperm towards the egg whereas if this push doesn’t happen then the sperm moves away from the egg.