Embryology Flashcards
Medulla of gametes
Cortex- female
Testes- male
Synthetic enzyme for removal of corona radiata
Hyolase
Enzymes in the acrosome that penetrate zona pellicuda by forming acrosomal reaction
Hyaluronidase
Acrosin
Trpsin like enzyme
Sperm abnormalities
Morphological: multiple heads and tail, fused sperms, gigantic or dwarfed sperms.
Genetic (rare)
Motility
Interphase of mitosis
DNA replication of chromosomes
Prophase of mitosis
Disappearance of nucleolus
Appearance of chromatids (indistinguishable)
Prometaphase of mitosis
Chromatically visible (distinguishable)
Metaphase of mitosis
Nuclear membrane breaks
Arrangement of chromosomes at equator
Appearance of spindle fibers from centrioles
Anaphase of mitosis
Splitting of centromere
Pulling of daughter chromosomes to opposite poles
Telophase of mitosis
Appearance of nucleolus
Formation of nuclear membranes
Cytokines and formation of 2 diploid cells
Prophase of meiosis
Leptotene Zygotene Pachytene Diplotene Diakenesis
Ootid?
An oocyte containing two haploid nuclei
Capacition of sperms
Removal of glycoproteins and seminal plasma proteins surrounding the acrosomal region of a sperm
Agenesis
refers to the failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue.
Tunica Abuginea
White capsule surrounding the testes that extends inwards and divides it into different lobes
What secretes Testosterone?
Interstitial cells of Leydig
Contents of prostatic fluid
Prostaglandins Acid phosphate Citric acid Prostate specific antigen Amylase Fribrinolysin
What secrets HCG?
Syncytiotrophoblast
Role of HCG
Indicates pregnancy
Retains the corpus luteum in order to continue secreting progesterone
Siamese
Conjoined twins
Conjoined twins at the chest are called?
Thoracopagus
How many hours does fertilization take approximately?
24hrs
When does cleavage begin?
In the uterine tube 30 hours after fertilization
When the primary chorionic villi formed?
Day 13
When is the prechordal plate formed?
Day 14
What induces zona/ cortical reaction?
Lysosomal enzymes released from cortical granules of the plasma membrane to penetrate the PM and prevent other sperms from passing through it or the ZP
What is closing plug?
A fibrous coagulum of blood at the site where the embryo sank into the endometrium
Placenta previa
Placenta that covers or blocks the os due to implantation at the inferior segment of the uterus near the internal os
Life spans of spermatozoa and oocyte respectively
72hrs
48hrs
Site for capacitation of sperms and time taken to complete it
Fallopian tube
5-7hrs
What aids the penetration of corona radiata
Tail movements
Mucosal enzyme hyaluronidase
Acrosome reaction
Release of acrosomal enzymes (HAT) for penetration of ZP
Totipotent
Capable of forming a complete embryo
Morphogenesis
Formation of body form due to gastrulation
Stimulated by morphogenic proteins, FGFs and Wnts
Sacrococcygeal teratoma
Persistence of primitive streak
Forms a tumor containing tissues from a three germ layers
Common in females
1 in 35,000
Vasculogenesis vs angiogenesis
Formation of new blood vessels from cell precursors called angioblast
Formation of new blood vessels from preexisting vessels
Amniocentesis
Amniotic fluid sampling to detect genetic disorders
Ultrasonography
Image modality for evaluation of the fetus to detect anomalies, measure size, etc
Alpha fetoprotein
A glycoprotein synthesized in the liver, umbilical cord and gut of the fetus.
High level of AFP in fetal serum indicates anomalies of CNS and ventral abdominal wall.
Low level in maternal serum indicates trisomy
Factors that affect fetal growth
Cigarette smoking Use of illicit drugs Multiple pregnancy Impaired uteroplacental/ fetoplacental blood flow Genetic factors
Ways of monitoring fetal status
Ultrasonography Amniocentesis Chorionic villus sampling MRI and CT Spectrophotometric studies Sex chromatin Alpha fetoprotein Percutenous Umbilical cord blood sampling Fetal transfusion Fetoscopy Fetal monitoring
Functions of placenta
Metabolism
Secretion of hormones
Transfer of nutrients and gases
Unfertilized secondary oocyte will last for?
24 - 48hrs in the ampulla
Amount of sperm in an ejaculate
200 - 350 million
Movement of ovum from ovary into uterine tube is by?
Sweeping of the fibria on the ovary
Cilia of the mucosal lining