Cleavage (embryo)In embryology, cleavage is the division of cells in the early development of the embryo, following fertilization but before amniogenesis. The zygotes of many species undergo rapid cell cycles with no significant overall growth, producing a cluster of cells the same size as the original zygote. The different cells derived from cleavage are called blastomeres and form a compact mass called the morula.
EmbryoAn embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres.
BlastulationBlastulation is the stage in early animal embryonic development that produces the blastula. In mammalian development, a blastula develops into the blastocyst with a differentiated inner cell mass and an outer trophectoderm. The blastula (from Greek βλαστός (blastos meaning sprout)) is a hollow sphere of cells known as blastomeres surrounding an inner fluid-filled cavity called the blastocoel.
Cellular differentiationStem cell differentiation into various animal tissue typesCell-count distribution featuring cellular differentiation for three types of cells (progenitor z{\displaystyle z}, osteoblast y{\displaystyle y}, and chondrocyte x{\displaystyle x}) exposed to pro-osteoblast stimulus.Cellular differentiation, also known as cellular specification, is the process in which a stem cell changes from one type to a differentiated one. Usually, the cell changes to a more specialized type.
BlastocystThe blastocyst is formed in the early embryonic development of mammals. It possesses an inner cell mass (ICM) also known as the embryoblast which subsequently forms the embryo, and an outer layer of epithelial cells called the trophectoderm. This layer surrounding the inner cell mass is responsible for the formation of the fluid-filled cavity or lumen known as the blastocoel. In the late blastocyst, the trophectoderm changes to trophoblast.
Anatomical terms of locationStandard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and axes.
Cell lineageCell lineage denotes the developmental history of a tissue or organ from the fertilized egg. This is based on the tracking of an organism's cellular ancestry due to the cell divisions and relocation as time progresses. This starts with the originator cells and finishes with a mature cell that can no longer divide. This type of lineage can be studied by marking a cell (with fluorescent molecules or other traceable markers) and following its progeny after cell division.
EpitheliumEpithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial (mesothelial) tissues line the outer surfaces of many internal organs, the corresponding inner surfaces of body cavities, and the inner surfaces of blood vessels. Epithelial tissue is one of the four basic types of animaltissue, along with connective tissue, muscle tissue and nervous tissue.
Cell (biology)Basic unit of life formsThe cell is the basic structural and functional unit of all forms of life or organisms. The term comes from the Latin word cellula meaning 'small room'. A biological cell basically consists of a semipermeablecell membrane enclosing cytoplasm that contains genetic material. Most cells are only visible under a microscope.
Gastrointestinal tractThe gastrointestinal tract (also called the GI tract, digestive tract, and the alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The tract is one of the largest of the body's systems. The GI tract contains all the major organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines.
Animal embryonic developmentIn developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell (spermatozoon). Once fertilized, the ovum becomes a single diploid cell known as a zygote.
AnimalBiological kingdomAnimals are multicellular, eukaryoticorganisms belonging to the biologicalkingdomAnimalia (). Animals consume organic material, breathe oxygen, have muscle cells, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. With few exceptions, animals are able to move. Animals form a clade, meaning that they arose from a single common ancestor.*As an Amazon Associate I earn from qualifying purchases.