Clase 6. Embriologia

Spermatogenesis

Spermatogenesis

The process of sperm production in males.

Spermatogonia

The cells that give rise to sperm cells.

Seminiferous tubules

The site of sperm production in the testes.

Spermiogenesis

The process of maturation of spermatids into spermatozoa.

Oogenesis

The process of egg cell production in females.

Oogonium

The cells that give rise to egg cells.

Blastomeres

The cells formed after the fertilized egg undergoes cellular division.

Morula

A solid ball of cells formed from the blastomeres.

Blastocyst

A stage of embryonic development characterized by the formation of a fluid-filled cavity.

Trophoblast

The outer cell mass of the blastocyst that contacts with the endometrium for implantation.

Embryoblast

The inner cell mass of the blastocyst that gives rise to the embryo.

Implantation

The process by which the embryo attaches to and embeds into the endometrium of the uterus.

Syncytiotrophoblast

The outer layer of the trophoblast that becomes continuous with the uterus during implantation.

Cytotrophoblast

The inner layer of the trophoblast that gives rise to the syncytiotrophoblast and other specialized cell types.

Placenta

An organ that develops during pregnancy and provides nutrients and oxygen to the developing fetus.

Placenta previa

A condition where the placenta implants in the lower uterine segment, potentially causing bleeding during pregnancy.

Blastocyst cavity

The fluid-filled cavity within the blastocyst.

Zona pellucida

A protective layer surrounding the egg cell.

Acrosome

A structure on the head of the sperm that contains enzymes for fertilization.

Amniotic cavity

The fluid-filled cavity that surrounds the developing embryo/fetus.

Ectopic pregnancy

Implantation of a fertilized ovum in a site other than the uterus, most often in the fallopian tube.

Isthmus

The highest risk area for tubal rupture in ectopic pregnancy.

Ampulla

The most common site for tubal pathologies in ectopic pregnancy.

Fallopian tube

The tube where ectopic pregnancy most often occurs.

Interstitium

The area of the fallopian tube where tubal rupture is most common in ectopic pregnancy.

Risk factors

Factors that increase the risk of ectopic pregnancy, such as tubal pathologies, previous ectopic pregnancy, IUD, and IVF.

Salpingitis

Inflammation of the fallopian tube, often caused by PID (pelvic inflammatory disease).

IVF

In vitro fertilization, a method of assisted reproductive technology.

Ovary

The female reproductive organ that produces eggs.

Infundibulum

The funnel-shaped end of the fallopian tube.

Fimbriae

Finger-like projections at the end of the fallopian tube that help capture the egg.

Normal pregnancy

A pregnancy that occurs in the uterus.

Methotrexate

A medication used to treat ectopic pregnancy.

Gastrulation

A process in embryonic development where the bilaminar disk undergoes cellular rearrangement to form three germ cell layers.

Bilaminar embryo

An embryo consisting of two cell layers, the epiblast and hypoblast.

Epiblast

The upper layer of the bilaminar embryo that gives rise to the three germ cell layers.

Hypoblast

The lower layer of the bilaminar embryo that contributes to the yolk sac.

Blastocyst

A stage of embryonic development characterized by the formation of a fluid-filled cavity.

Endoderm

One of the three germ cell layers formed during gastrulation, which gives rise to the gut tube epithelium and other structures.

Mesoderm

One of the three germ cell layers formed during gastrulation, which gives rise to muscle, bone, connective tissue, and other structures.

Ectoderm

One of the three germ cell layers formed during gastrulation, which gives rise to the epidermis, nervous system, and other structures.

Trilaminar embryo

An embryo consisting of three germ cell layers - endoderm, mesoderm, and ectoderm.

Neural tube

A structure formed from the folding of the ectoderm during embryonic development, which gives rise to the brain and spinal cord.

Neural crest

A group of cells that migrate from the neural tube and give rise to various structures, including PNS neurons and melanocytes.

Mesoderm

The middle germ cell layer formed during gastrulation, which gives rise to muscle, bone, connective tissue, and other structures.

VACTERL association

A condition characterized by multiple congenital anomalies affecting the vertebral column, anus, cardiac structures, trachea, esophagus, renal system, and limbs.

Telencephalon

The anterior part of the developing brain, which gives rise to the cerebral hemispheres.

Diencephalon

The part of the developing brain that includes the thalamus and hypothalamus.

Neural development

The process of formation and differentiation of the nervous system during embryonic development.

Neural plate

A thickened region of the ectoderm that gives rise to the neural tube.

Neural fold

The raised edges of the neural plate that fuse together to form the neural tube.

Neural groove

The groove formed by the invagination of the neural plate.

Cerebral hemispheres

The two halves of the cerebrum, which are the largest part of the brain.

Basal ganglia

A group of structures located deep within the cerebral hemispheres that are involved in motor control.

Forebrain

The anterior part of the developing brain, which includes the telencephalon and diencephalon.

Midbrain

The middle part of the developing brain, which includes the mesencephalon.

Hindbrain

The posterior part of the developing brain, which includes the metencephalon and myelencephalon.

Cerebellum

A structure located in the hindbrain that is involved in motor coordination and balance.

Medulla

The lower part of the hindbrain that connects to the spinal cord.

Spinal cord

The long, tubular structure that extends from the brain and is responsible for transmitting signals between the brain and the rest of the body.

Folic Acid

A vitamin supplement recommended for women planning a pregnancy or capable of becoming pregnant to prevent neural tube defects.

Neural Tube Defects

Failure of the neural tube to close completely during fetal development, associated with maternal folate deficiency during pregnancy.

Spina Bifida Occulta

A closed neural tube defect where the caudal neural tube fails to close completely, but there is no herniation. It is usually seen at lower vertebral levels and may be associated with a tuft of hair or skin dimple at the level of the bony defect.

Meningocele

An open neural tube defect where the meninges (but no neural tissue) herniate through a bony defect.

Myelomeningocele

An open neural tube defect where both the meninges and neural tissue (such as the cauda equina) herniate through a bony defect.

Anencephaly

An open neural tube defect where the rostral neuropore fails to close, resulting in the absence of the forebrain and an open calvarium. It is often associated with polyhydramnios.

Holoprosencephaly

A brain malformation characterized by the failure of the forebrain to divide into two cerebral hemispheres. It is associated with SHH mutations and may be seen in conditions like trisomy 13 and fetal alcohol syndrome.

Lissencephaly

A brain malformation characterized by the failure of neuronal migration, resulting in a smooth brain surface without the usual sulci and gyri. It presents with dysphagia, seizures, microcephaly, and facial anomalies.

Blastocyst

The stage of embryonic development where the fertilized egg has formed a fluid-filled cavity and consists of an inner cell mass (epiblast) and an outer layer of cells (trophoblast).

Gastrulation

The process during embryonic development where the epiblast cells invaginate through the primitive streak, forming the three germ layers:endoderm, mesoderm, and ectoderm.

Notochord

A structure that arises from the midline mesoderm and induces the overlying ectoderm to become the neural plate, which eventually forms the neural tube.

Genital Embryology

The development of the reproductive organs during embryonic development.

Paramesonephric Duct

The duct that develops in females and gives rise to the fallopian tubes, uterus, and proximal vagina.

Mesonephric Duct

The duct that develops in males and gives rise to the epididymis, vas deferens, and seminal vesicles.

Uterine Anomalies

Abnormalities in the structure of the uterus, such as septate uterus (incomplete resorption of the septum) and bicornuate uterus (incomplete fusion of the Müllerian ducts).

Períodos de susceptibilidad a los teratógenos

Periods of susceptibility to teratogens (teratogenesis) during embryonic development.

Teratogens

Substances or factors that can cause birth defects or abnormalities in a developing fetus.

Organogenesis

The process of organ formation during embryonic development.

All-or-none effect

The concept that teratogens can have a severe impact on the fetus before implantation, either causing complete absence of the organ or no effect at all.

ACE inhibitors

Medications that can cause renal failure, oligohydramnios (low amniotic fluid), and hypocalvaria (underdeveloped skull bones) in the fetus.

Alkylating agents

Medications that can cause multiple anomalies in the fetus, such as ear and facial abnormalities and absence of digits.

Aminoglycosides

Medications that can cause ototoxicity (hearing loss) in the fetus.

Antiepileptic drugs

Medications used to treat epilepsy that can cause neural tube defects, cardiac defects, cleft palate, and skeletal abnormalities in the fetus. Valproate, carbamazepine, phenytoin, and phenobarbital are commonly associated with these effects.

Diethylstilbestrol

A synthetic estrogen that can cause vaginal clear cell adenocarcinoma and congenital Mullerian anomalies in female offspring.

Fluoroquinolones

Antibiotics that can cause cartilage damage in the fetus.

Folate antagonists

Substances that interfere with the function of folate, leading to neural tube defects in the fetus. Trimethoprim and methotrexate are commonly associated with these effects.

Isotretinoin

A medication used to treat severe acne that can cause craniofacial defects, CNS abnormalities, cardiac defects, and thymic defects in the fetus. Contraception is mandatory during its use.

Lithium

A medication used to treat bipolar disorder that can cause Ebstein anomaly (a heart defect) in the fetus.

Methimazole

A medication used to treat hyperthyroidism that can cause aplasia cutis congenita (absence of skin) in the fetus, typically on the scalp.

Tetracyclines

Antibiotics that can cause discolored teeth and inhibited bone growth in the fetus.

Thalidomide

A medication that was once used as a sedative and caused limb defects, such as phocomelia (flipper-like limbs), in the fetus.

Warfarin

An anticoagulant medication that can cause bone and cartilage deformities, optic nerve atrophy, and cerebral hemorrhage in the fetus. Heparin is used as an alternative during pregnancy.

Alcohol

Consumption of alcohol during pregnancy can cause fetal alcohol syndrome, which is characterized by physical and developmental abnormalities in the fetus.

Cocaine

Use of cocaine during pregnancy can lead to preterm birth, low birth weight, fetal growth restriction, and vasoconstriction in the fetus.

Tobacco smoking

Smoking tobacco during pregnancy can result in preterm birth, low birth weight, fetal growth restriction, sudden infant death syndrome (SIDS), and attention deficit hyperactivity disorder (ADHD) in the offspring. Nicotine and carbon monoxide are the main substances responsible for these effects.

Iodine deficiency or excess

Lack or excess of iodine during pregnancy can cause congenital hypothyroidism in the fetus.

Maternal diabetes

Diabetes in the mother during pregnancy can lead to various complications in the fetus, including caudal regression syndrome, cardiac defects, neural tube defects, macrosomia (large body size), neonatal hypoglycemia, polycythemia, and respiratory distress syndrome.

Maternal PKU

Phenylketonuria (PKU) in the mother during pregnancy can result in fetal growth restriction, microcephaly, intellectual disability, and congenital heart defects.

Agenesis

Absence of an organ due to the absence of primordial tissue.

Aplasia

Absence of an organ despite the presence of primordial tissue.