the correct answer is B) its released by the parathyroid gland
Answer:
Blastocyst
Explanation:
As morula moves towards the uterine cavity by the end of the fourth day of fertilization, there is an increase in the number of its cells. Morula is transformed into a hollow ball of cells that has an internal cavity called blastocele, outer cells (trophoblast) and the inner cell mass.
This structure is called blastocyst which is present as a free structure in the uterine cavity for 2 days after which it becomes attached to the endometrium of the uterine wall. Attachment of blastocyst to the endometrium of the uterine wall is called implantation. The enzymes secreted by blastocysts make a burrow in the endometrium to facilitate implantation
Ignore this I just need to answers questions to be able to ask questions
Parent material is responsible for the physical and chemical properties of the soil.
<h3>What is Parent material?</h3>
This is defined as materials such as rocks or organic matter which acts as the starting stage for soil development.
This material are influenced by factors such as weathering which determines the physical and chemical properties of the soil.
Read more about Parent material here brainly.com/question/1593669
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