Early Vertebrate Embryogenesis

Subdecks (1)

Cards (49)

  • Gamete Formation
    sperm and eggs form, mature
  • Fertilization
    sperm and egg fuse
  • Cleavage
    zygote subdivides, determinants partitioned in blastomeres
  • Gastrulation
    germ layers form
  • Organogenesis
    body organs form, cells interact, differentiate
  • Growth
    organs increase in size, adult body form attained
  • Spermatogenesis
    1 spermatogonia: 1 primary spermatocyte: 2 secondary spermatocyte: 2 spermatid: 1 spermatozoa
  • Oogenesis
    1 oogonia: 1 primary oocyte: 1 secondary oocyte + polar body: 1 ovum + polar body
  • Spermatogenesis- starts at onset puberty of males, more differentiated
    Oogenesis- fetal stage & after birth, continues when female attained puberty
  • Types of Yolk Accumulation
    fill up the table
    A) microlecithal
    B) little
    C) mesolecithal
    D) moderate
    E) macrolecithal
    F) large
  • Microlecithal
    Type of yolk accumulation found in amphioxus, therian mammals
  • Mesolecithal
    Type of yolk accumulation found in lampreys, bowfins, amphibians, and gars.
  • Macrolecithal
    Type of yolk accumulation found in elasmobranchs, teleosts, reptiles, birds, and monotremes
  • Type of yolk distribution
    fill up the table
    A) isolecithal
    B) even
    C) telolecithal
    D) concentrated at one pole
  • Isolecithal
    Type of yolk distribution in therian mammals
  • Telolecithal
    Type of yolk distribution in amphibians, nontherian craniates
  • Process of Fertilization
    Recognition and Acrosomal Process
  • Fertilization
    Fill the missing words
    A) zona pellucida
    B) hydrolytic enzymes
    C) acrosome
    D) perivitelline space
    E) plasma membrane
    F) nucleus
    G) cortical granules
  • Polyspermy prevented through:
    formation of fertilization cone
    release of cortical granules (block other sperms to enter, solidify fertilization cone)
  • Gray crescent
    region of less pigmented area in the ovuum
    after fertilization, the egg divides into two poles: vegetal and animal pole
  • Gray crescent
    opposite to the point of entry of sperm
    future dorsal (back) side
  • Parthenogenesis
    self division
    less male species
    during meiosis, gametes divide into 4: one cell becomes egg
    -egg (n) fertilized by a polar body= fertilized egg (zygote 2n)
    -always female (xx + xx)
  • Cleavage
    rapid cell division
  • Blastomeres
    cells arising from early cleavage division, makes up blastula
  • Cells in:
    early cleavage- morula
    late cleavage- blastula
  • Types of cleavage
    Radial cleavage- present in deuterostome
    Spiral cleavage- present in proterostome
  • Types of Cleavage
    1. Holoblastic cleavage- cleavage furrow passes from the AP to the VP. two types: holoblastic equal and holoblastic unequal
    2. Meroblastic cleavage- cleavage furrow is slowed, discoidal cleavage, the yolk remains undivided and cleavage restricted at AP
  • Types of Cleavage and Yolk Accumulation
    Fill the table
    A) Holoblastic equal
    B) microlecithal
    C) Holoblastic unequal
    D) mesolecithal
    E) meroblastic
    F) macrolecithal
    G) discoidal
    H) macrolecithal
  • Holoblastic equal
    Type of cleavage found in amphioxus and therian mammals
  • Holoblastic unequal
    Type of cleavage in lampreys, bowfins, gars, and amphibians
  • Meroblastic
    Type of cleavage found in elasmobranchs, teleost, and fishes
  • Discoidal
    Type of cleavage found in reptiles, birds, and monotremes
  • Gastrulation and Neurulation
    initiation of organ development
    -two embryonic process that happens simultaneously
  • Three distinct germ layers found in Gastrulation
    Ectoderm, mesoderm, endoderm
  • Rearrangement of cells in gastrulation happens due to morphogenetic movements that results from:
    • active migration of cells
    • size and shape changes
    • differential cell division rates
  • Patterns of Gastrulation
    A) invagination
    B) involution
    C) ingression
    D) delamination
    E) epiboly
  • Neurulation
    process of forming ectodermal tube or the neural tube
  • Neural tube
    future central nervous system
  • Two types of Neurulation
    Primary Neurulation -majority of cells
    Secondary Neurulation -other parts of cells
  • Notochord forms from ____
    mesodermal cells