What does the trophoblast develop into?
Trophoblasts (from Greek to feed: threphein) are cells forming the outer layer of a blastocyst, which provides nutrients to the embryo, and develops into a large part of the placenta. They are formed during the first stage of pregnancy and are the first cells to differentiate from the fertilized egg.
What are the types of trophoblast?
There are three types of trophoblasts: cytotrophoblasts, syncytiotrophoblasts, and intermediate trophoblasts (ITs). Cytotrophoblasts may be easily seen histologically as the inner cell layer of the chorionic villi in normal first trimester gestations (Figure 1(a)).
What is trophoblast in biology?
Listen to pronunciation. (TROH-foh-BLAST) A thin layer of cells that helps a developing embryo attach to the wall of the uterus, protects the embryo, and forms a part of the placenta.
What is a trophoblastic tissue?
The trophoblast is the outer layer of cells surrounding the embryo. It has many small projections (called chorionic villi) that grow into the lining of the uterus. The layers of the trophoblast form the tissue that will become the placenta and the membranes that surround the embryo.
What is the difference between trophoblast and chorion?
Trophoblast refers to the layer of cells on the outside of the mammalian blastula. The major function of the trophoblast is the nourishment of the embryo by forming the major part of the placenta. It gives rise to the extra embryonic structure called chorion. The chorion is the fetal part of the placenta.
What is trophoblast cells?
(TROH-foh-BLAST) A thin layer of cells that helps a developing embryo attach to the wall of the uterus, protects the embryo, and forms a part of the placenta.
What are the layers of the trophoblast?
The trophoblast is subdivided into two layers, the inner cytotrophoblast, which proliferates upon implantation, and the outer syncytiotrophoblast, which supports cytotrophoblast proliferation through contact with the maternal blood.
What is the circulatory system in mammals?
Circulatory system. In mammals, as in birds, the right and left ventricles of the heart are completely separated, so that pulmonary (lung) and systemic (body) circulations are completely independent.
What are the basic circulatory systems of some vertebrates?
The figure below illustrates the basic circulatory systems of some vertebrates: fish, amphibians, reptiles, and mammals. (a) Fish have the simplest circulatory systems of the vertebrates: blood flows unidirectionally from the two-chambered heart through the gills and then the rest of the body.
What are the different types of circulatory systems?
Compare and contrast the organization/function of circulatory systems, including gastrovascular cavity, open, closed, single, and double systems Identify and describe the functions of different types of blood vessels (artery, arteriole, capillary, venule, vein), including their basic structure
Do animals with one cell layer have a circulatory system?
Simple animals consisting of a single cell layer such as the (a) sponge or only a few cell layers such as the (b) jellyfish do not have a circulatory system. Instead, gases, nutrients, and wastes are exchanged by diffusion.