What is the meaning of stomodeum?
Definition of stomodeum : the embryonic anterior ectodermal part of the digestive tract.
What is stomodeum in cnidaria?
Anatomical terminology. The stomodeum, also called stomatodeum or stomatodaeum, is a depression between the brain and the pericardium in an embryo, and is the precursor to the mouth and the anterior lobe of the pituitary gland.
What is the primordial mouth?
The proctodeum (anal pit) is the primordial anus, and the stomodeum is the primordial mouth. In both of these areas ectoderm is in direct contact with endoderm without intervening mesoderm, eventually leading to degeneration of both tissue layers.
What separates the stomodeum from the foregut?
The stomodeum is lined by ectoderm, and is separated from the anterior end of the fore-gut by the buccopharyngeal membrane.
What is the Proctodeum?
proctodeum. n. pl. proc•to•de•ums. An inward fold on the surface of the embryonic ectoderm that develops into part of the anal passage.
What is Siphonoglyph in zoology?
The siphonoglyph is a ciliated groove at one or both ends of the mouth of sea anemones and some corals. The siphonoglyph extends into a pharynx and is used to create currents of water into the pharynx. These water currents are important for respiration and maintenance of internal pressure.
What is pharyngeal arch?
Pharyngeal arches develop from the cephalic (head) portion of the neural crest, which is a strip of tissue that runs down the back of the embryo and gives rise to a large number of different organs. Pharyngeal arches produce the cartilage, bone, nerves, muscles, glands, and connective tissue of the face and neck.
How is stomodeum formed?
The stomodeum (mouth) forms on the oral side where the invaginating archenteron fuses with the overlying ectoderm, whereas the ciliary band of neurogenic cells forms at the interface of oral and aboral ectoderm.
What is stomodeum in cockroach?
Stomadeum of cockroach is foregut or hindgut.
What is primitive oral cavity?
The primitive mouth cavity is evident as a slit-like space lined by ectoderm in the 3–4-week-old human embryo. It is located under the surface of the brain capsule and above the pericardial sac where the heart forms. The mouth cavity is still separated from the primitive pharynx by the oropharyngeal membrane.
What is the Coprodeum?
The coprodeum collects the fecal matter from the colon. The urodeum is the area that collects urine directly from the ureters or bladder. The reproductive tract also connects with the urodeum. The urodeum and coprodeum then empty into the proctodeum before being excreted outside of the body.
Definition of stomodeum. : the embryonic anterior ectodermal part of the digestive tract.
What is the meaning of stomadeal?
a depression in the ectoderm located in the foregut of the developing embryo that forms the mouth. Also spelled stomadaeum, stomadeum, stomodaeum. Compare proctodeum. stomadeal, stomodaeal, stomodeal, adj.
Is the stomodeum derived from the blastopore?
The stomodeum does not appear to be derived from either the blastopore or the area in which the blastopore forms. In this type, the stomodeum fused to the anterior tip of the archenteron and then the archenteron differentiated into intestine, stomach, and esophagus.
What is stomatodeum in anatomy?
, stomatodeum (stō’mō-dē’ŭm, -mă-tō-dēŭm) A midline ectodermal depression ventral to the embryonic brain and surrounded by the mandibular arch; when the buccopharyngeal membrane disappears, the stomodeum becomes continuous with the foregut and forms the mouth.