Cell Biology and Human Embryonic Development Essentials
Bacteria are unicellular microorganisms that have a size of some micrometers long (between 0.5 and 5 ìm, usually) and different shapes including spheres, rods and hélices.Hook cell discovered in 1667. Jassen brothers discovered the microscope.
The HICAS .- is an enzyme that opens the DNA chain
Classes of RNA: transfer, messenger, ribosomal
4 nitrogenous bases: cytokine, guanine, thymine, adenine
4 forms of cells: nerve, streptococcus, amoeba, monococo
Mitosis: prophase, metaphase, anaphase, telophase, interphase
Centromere: The zone where the chromosome interacts with the spindle fibers from prophase to anaphase, both in mitosis and in meiosis Reproduction <http://es.Wikipedia.Org/wiki/Mitosis> cells: bipartition gemancion, sporulation
.- Haploid cells with half the chromosomes (N)
.- Diploid cells with complete chromosomes (2N)
Gametogenesis .- process by which originate gametes or sex cells
..- Aims spermatogenesis sperm formation
.- Oogenesis is intended to provoke the ovules
.- Mitosis is a process of fair sharing of genetic material, concludes with the formation of separate cell
.- Meiosis is a sexual process, originates diploid daughter cells
Embryonic development:
.- Segmentation is performed on the path toward the uterus onioducto
Gastrulation .- Gastulo is formed from the glastula, there are 3 layers: ectoderm, mesoderm, endoderm
Differentiation .- is a specialization of tissues and organs of the embryo. Ectoderm: skin, senses, nerves. Mesoderm: muscle, bone, blood, heart, and kidneys gonadass. Endoderm: lungs, liver, pancreas, digestive system
Amniotic fluid is a liquid that surrounds and cushions the embryo <and then the developing fetus inside the amniotic sac Embryology:
First month the developing organism is called an embryo, there are the rudimentary brain spinal muscles, bones
Second month .- develop structures that formed in the first month, distinguishes the brain and head, the ears are marked regions of the fingers, empienza to form the reproductive organs.
Third month .- start developing lung and kidney at the end of this month all the organs are already formed (7.5cm 28gr)
Fourth and fifth month .- There is accelerated growth of the fetus (30cm-1/2kilo) is made of bone calcification
Sixth month .- showing clear periods of sleep (35cm-1kg)
Third quarter .- the fetus grows to such a degree that does not fit in the space and uterine tissue and amniotic fluid weigh half that the fetus itself. Shortly before birth the fetus's head fits in the bottom of the uterus. (50cm-3.5Kg)
Stages of labor
First .- shows the uterine contractions and begins the dilation of the cervix ruptures the amniotic sac
Second .- cervix is fully dilated and the baby is expelled
Third .- The placenta is expelled and placentas