Fertilization Spermatozoa maturation steps The maturation and activation
- Slides: 37
Fertilization
Spermatozoa maturation steps
The maturation and activation of the spermatozoa occur in the following four steps: • • Storage in the epididymis Maturation Ejaculation Activation Ascension to the ovary Capacitation Near the oocyte Acrosome reaction
Composition of the seminal plasma Amount 2 -100 ml p. H value 7 -8 (light alkaline buffer) Seminal gland secretion 75% of the volume, alkaline fructose-rich secretion (1. 5 -6. 5 mg/ml fructose), phosphorylcholine, ascorbic acid Prostate secretion 20%-25% of the volume, biogenic amine (spermidine, spermine), citric acid, cholesterol, phospholipids, protease to fluidize the ejaculate (fibrinolysin, fibrinogenase) Further components Phosphate and bicarbonate as buffer, prostaglandin,
Human
COW
MARE SOW
Maturation of the oocyte in the dominant follicle shortly before ovulation
Termination of the first meiosis
The secondary oocyte
The follicle that is about to rupture
Secondary oocyte in metaphase 2
The acquisition of the oocyte by the fallopian tube
Consequences of multiple ovulation • Twin pregnancy • from one mating male • Superfecundation: from two males, after synchrone ovulation • Superfoetation: from two males, after asynchrone ovulation
Formation of a bilaminar germ disk • In the bilaminar primordium of the embryo (hypoblast or primary endoderm and epiblast) one recognizes in the epithelium of the epiblast a fluid-filled space, the first primordium of the amniotic cavity. • Ventrally, the roof of the still incompletely uncovered primary umbilical vesicle (previously the blastocyst cavity) is formed by the hypoblast.
Develomental differences in early embriogenesis • A: Folding (Carnivores, Rodents, Ungulate (hoofed animal) • B: Exocoel formation (Primates, Human, Insectivores)
1. Extra-embryonic mesoblast 2. Extra-embryonic reticulum 3. Primary umbilical vesicle 4. Cytotrophoblast 5. Lacunae in the reticulum 6. Hypoblast 7. Heuser´s membrane between hypoblast and mesoblast cells
Formation of the ‘Trilaminar germ disc’ AKA epithelio-mesenchymal transition • Immigrated cells form a third germinal layer: the intraembryonic mesoblast • The mesoblast cells wander in all directions: laterally, cranially and caudally. • This middle germinal layer lies between the definitive endoblast and epiblast. • Exceptions are the cloacal membrane as well as the pharyngeal membrane, where the ectoderm and endoderm lie directly opposite each other!
- Internal vs external fertilization
- Activation tree example
- Masa abstinensia untuk analisis sperma adalah...
- Amorphous urates in urine ph
- Axial movement of the body
- Sahar anwar
- Learning is defined as
- Thymosin and thymopoietin assist in the maturation of:
- Chapter 39 endocrine and reproductive systems
- Lesson 15.4 ovulation fertilization and implantation
- Physiological function of estrogen
- Periblastula
- How does temperature affect rate of reaction
- Activation and passivation in adf
- Factors affecting rate of chemical reaction
- Maturation definition
- Seed maturation
- What is gesell's maturation theory
- Affinity maturation somatic hypermutation
- Arnold gesell theory
- Regression threat
- Relationship between development and learning
- Maturation index 0/90/10
- Macrocytic hypochromic anemia
- Ameloblast stages
- The incomplete man
- Maturation
- Schuffner's granules
- What is maturation
- Proerythroblast
- Fertilization
- Horse internal or external fertilization
- Human reproductive system
- Fertilization occurs
- First week of development
- Angiosperms double fertilization
- Salamander fertilization
- Post fertilization events