blástula – מילון אנגלי-אנגלי
blastula
n.
(Embryology) cavity surrounded by a single layer of cells (first stage in the life of an embryo)
Blastula
The
blastula (from Greek (blastos), meaning "sprout") is a hollow sphere of
cells, referred to as
blastomeres, surrounding an inner fluid-filled cavity called the
blastocoele formed during an early stage of
embryonic development in
animals.
Embryo development begins with a sperm fertilizing an egg to become a
zygote which undergoes many
cleavages to develop into a ball of cells called a
morula. Only when the blastocoele is formed does the early embryo become a blastula. The blastula precedes the formation of the
gastrula in which the
germ layers of the embryo form.
blastula
Noun
1. early stage of an embryo produced by cleavage of an ovum; a liquid-filled sphere whose wall is composed of a single layer of cells; during this stage (about eight days after fertilization) implantation in the wall of the uterus occurs
(synonym) blastodermic vesicle
(hypernym) embryo, conceptus, fertilized egg
(hyponym) blastosphere, blastocyst
(part-meronym) blastocoel, blastocoele, blastocele, segmentation cavity, cleavage cavity
Blastula (die)
nf.
blastula, cavity surrounded by a single layer of cells (Embryology)
blastula
nf.
blastosphere, (Embryology) blastula, cavity surrounded by a single layer of cells (first stage in the life of an embryo)
