Copulation, Fertilization and Development Biology 2122

Male Sexual Response (1) Erection – Parasympathetic reflex Affects arterioles – Nitric oxide and smooth muscle (2) Ejaculation – Sympathetic control – L 1 and L 2

Fertilization (1) Sperm – making it into the fallopian tube – Capacitation (2) Penetration and Acrosomal Response – Corona Radiata – Hyaluronidase – Zona Pellucida and ZP3 Glycoprotein – Acrosomal reaction – Acrosomal process

Polyspermy (1) Monospermy – Cortical reaction – ZIP’s – Slow Block (2) Completion of Meiosis II – Formation of Male Pronucleus – Female Pronucleus (3) Fertilization – Formation of the Zygote

Embryonic Development – Cleavage and Blastocyst Formation (1) Cleavage – Blastomeres (2-cell stage) – Morula – Days 3-4 (100 cells or more) (2) Blastocyst – Trophoblast cells – Inner cell mass – Emybryonic disc

Implantation (1) 6-7 days – “Window of Implantation” (2) Endometrial cell preparation – Integrin binding (3) Trophoblast cells – Digestive enzymes and growth factors – Endometrial thickening (4) Trophoblast development – Cytotrophoblast – Syncytiotrophoblast – hCG

Placentation (1) Placenta – Inner cell mass – Chorion and Chorionic Villi – Intervillius spaces – Decidua basalis – Decidua capsularis (2) Decidua – Birth

Placentation

Gastrula Formation (1) Gastrula – Germ layer formation (2) Embyronic disc – Inner cell mass – Epiblast and hypoblast (3) Extraembryonic Membranes – Amnion – Yolk sac – Allantios – Umbillical cord

Formation of Primary Germ Layers

Differentation of Germ Layers – Organogenesis (1) Primary Germ Layers – Endoderm – Mesoderm – Ecoderm (2) Differentation of Germ Layers – Ectoderm Brain and spinal cord – Mesoderm Somites Sclerotome; dermatome and myotome Somatic mesoderm Splanchnic mesoderm – Endoderm Primitive Gut

Ectoderm Tissue AreaTissue Formed (1). NeuralAll nervous tissue! (2). SkinEpidermis, hairs, follicles, sweat and oil glands (3). EyeCornea and lens (4). TeethEnamel (5). GlandsEpithelium of pineal, pituitary and adrenal (6). Skin colorMelanocytes (7). BonesSome cranial bones (8). Nasal CavityEpithelium of nasal cavity, paranasal sinues (9). DigestiveEpithelium of anal canal

Endoderm Tissue Formation AreaTissue Formed (1). GI TractEpithelium of all except for oral and anal areas (2). Digestive TractAccessory glands (pancreas and liver) (3). Respiratory TractAll Epithelium of respiratory tract and auditory tube; also of tonsils (4). GlandsThyroid, parathyroid and thymus (5). ReproductiveAll epithelium of reproductive ducts and glands (6). UrinaryAll epithelium of urethra and bladder

Endoderm Differentiation Figure 28.11

Somites - Mesoderm TypeDescription (1). SclerotomeProduce vertebra and rib (2). DermatomeOuter wall of somites; form dermis of skin in dorsal area of the body (3). MyotomeSkeletal muscles of the neck, body trunk and limbs (via limb buds) *Intermediate Mesoderm Gonads and kidneys **Lateral Mesoderm (a). Somatic Mesoderm Dermis of skin – ventral; parietal serosa – ventral body cavity; bones ligaments and dermis of limbs (b). Splanchnic Mesoderm Heart, blood vessels and most connective tissue

Mesoderm Tissues AreaTissue (1). MuscleAll types (skeletal, smooth and cardiac) (2). BoneAll cartilage, bone and connective tissues (3). BloodAll parts, bone marrow and lymph tissue (4). EpitheliumEndothelium of BVs, lymph vessels (5). EyeFibrous and vascular tunics (6). JointsSynovial membranes of cavities (7). OrgansUreters, kidneys, gonads, reproductive ducts of male and female

Fetal Development and Labor (1) Know events in table 28.1 ! (2) Labor – Hormonal activation – Braxton Hicks contractions – Oxytocin and Prostaglandins (3) Stages of Labor – Dilation 10 cm 6-12 hours average – Expulsion Crowning – Placental Stage

Effects of Pregnancy (1) Anatomical Changes – Lordosis – Weight Gain (2) Metabolic Changes – hPL and hCS – hCT (3) Physiological Changes – GI – Urinary – Respiratory – Cardiovascular

Sexual Differentation (1) Gonadal Ridges- Sexually Indifferent Stage – Mullerian ducts – Wolffian ducts (2) Primordial Germ Cells – Seeding stem cells (3) Week 7 and 8 – Seminiferous tubule formation – Female process – week 8 (4) External Genitalia – Genital tubercle

Structures General Tubercle  Penis and Clitorus Urethral folds  spongy urethra (penis) – fused Unfused Urethral folds  labia minora; unfused labioscrotal folds  labia majora Labioscrotal swellings fuse  scrotum Gonadal Ridges  Testes and ovaries Formation of accessory structures and external genitalia depends on presence or absence of testosterone – Formation of testes  testosterone