ANIMAL DEVELOPMENT

1
CHAPTER 47

• ANIMAL DEVELOPMENT

2

• ANIMAL DEVELOPMENT
• GAMETOGENISIS
• EMBRYONIC DEVELOPMENT (FERTILIZATION TO BIRTH)
• PROCESS THAT LEADS TO SEXUAL MATURITY
• AGING PROCESS DEATH
• SOME ANIMALS MAY APPEAR DIFFERENT FROM IMMATURE
  TO ADULT STAGE. PROCESS IS KNOWN AS
  METAMORPHOSIS (TADPOLE-FROG, CATERPILLAR-MOTH)
• SOME ANIMALS THE BIRTH OF AN INFANT RESEMBLE THE
  ADULT FORM
• 2 STAGES EMBRYONIC FETAL. THE FETAL
  RESEMBLES THE ADULT

3

• EMBRYONIC DEVELOPMENT
• FERTILIZATION SPERM PENETRATES THE PLASMA
  MEMBRANE OF THE EGG
• RECOGNITION VITALLINE LAYER (ANIMALS) INSURES
  THAT THE SAME SPECIES OF SPERM UNITES WITH THE
  EGG. (ZONA PELLUCIDA-HUMANS)
• PENETRATION SPERM AND EGG PLASMA MEMBRANES FUSE
  AND THE SPERM NUCLEUS ENTERS THE EGG
• FERTILIZATION MEMBRANE FORMED WHICH BLOCKS THE
  ENTRANCE OF ADDITONAL SPERM
• COMPLETION OF MEIOSIS II IN THE EGG IN HUMANS
  THIS IS TRIGGERED BY SPERM ENTERING AND POLAR
  BODIES ARE RELEASED
• FUSION OF NUCLEI DNA REPLICATION

4
(No Transcript)
5
(No Transcript)
6

• CLEAVAGE
• ZYGOTE BEGINS A SERIES OF DIVISIONS THAT ARE
  RAPID, WITHOUT CELL GROWTH
• BLASOMERE CONTAINS LESS CYTOPLASM THAN THE
  ORIGINAL ZYGOTE
• EMBRYO POLARITY ANIMAL POLE (UPPER) VEGETAL
  POLE (LOWER) CONTAIN STORED FOOD (YOLK) AND IS
  DENSER AND WILL SETTLE TO THE BOTTOM

7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10

• POLAR AND EQUATORIAL CLEAVAGE
• EARLY CLEAVAGE DIVIDES INTO SEGMENTS THAT STRETCH
  FROM POLE TO POLE
• EQUATORIAL IS PERPENDICULAR TO POLAR CLEAVAGE

11

• RADIAL AND SPIRAL CLEAVAGE
• DEUTEROSTOMES EARLY CLEAVAGE ARE RADIAL,
  FORMING CELLS THAT ARE ALIGNED DIRECTLY ABOVE AND
  BELOW EACH OTHER
• PROTOSTOMES SPIRAL CLEAVAGE, THE TOP CELLS ARE
  NOT LINED UP OVER THE BOTTOM CELLS

12

• INDETERMANT CLEAVAGE
• RADIAL CLEAVAGE OF DEUTERSTOMES THAT WILL PRODUCE
  A BLASTOMERE THAT CAN INDIVIDUALLY FINISH
  DEVELOPMENT

13

• DETERMINANT CLEAVAGE
• SPIRAL CLEAVAGE OF PROTOSTOME, BLASTOMERE CANNOT
  DEVELOP INTO A COMPLETE EMBRYO. IT WILL
  CONTRIBUTE TO ONLY PART OF THE EMBRYONIC
  DEVELOPMENT

14

• MORULA SOLID MASS OF CELLS
• BLASTULA LUQUID FILLS THE MORULA, AND CREATES A
  HOLLOW SPHERE (BLASTOCOEL CAVITY)
• GASTRULA
• GASTRULATION CELLS BEGIN TO INVAGINATE TO FORM
  A TWO LAYERED EMBRYO OPENING FROM THE OUTSIDE
  INTO A CENTER CAVITY. POSSES THE FOLLOWING
  FEATURES
• 3 GERM LAYERS ECTO, ENDO MESODERM
• ARCHENTERON CENTRAL CAVITY
• BLASTOPORE OPENING INTO THE ARCHENTERON
• PROTSTOME MOUTH
• DEUTERSTOME - ANUS

15

• EXTRAEMBRYONIC MEMBRANES
• IN AMNIOTES (BIRDS, REPTILES HUMANS)
• CHORION OUTER MEMBRANE. GAS EXCHANGE IN BIRDS
  REPTILES. IN MAMMALS ALONG WITH MATERNAL
  TISSUE FORM THE PLACENTA (GAS, NUTRIENT AND WASTE
  EXCHANGE)
• ALLANTOIS SAC THAT BUDS OFF OF THE ARCHENTERON
  AND ENCIRCLES THE EMBRYO, LAYER BELOW HE CHORION.
  IN MAMMALS FORMS THE UMBILICAL CORD. BIRDS
  REPTILES STORES NITROGENOUS WASTE FUSES WITH
  THE CHORION IN GAS EXCHANGE
• AMNION ENCLOSES AMNIOTIC SAC, FLUID FILLED FOR
  SHOCK ABSORPTION
• YOLK SAC FOOD (BIRDS REPTILES). MAMMALS
  FOOD IS FROM THE PLACENTA

16
(No Transcript)
17

• ORGANOGENESIS
• CELLS ALONG THE DORSAL SURFACE OF THE MESODERM
  FORM A STIFF ROD FOR SUPPORT
• NEURAL TUBE ECTODERM LAYER THAT IS DIRECTLY
  ABOVE THE NOTOCHORD AND WILL FORM THE NEURAL
  PLATE WHICH INDENTS TO FORM THE NEURAL GROOVE
  WHICH ROLLS INTO A CYLINDER TO FORM THE NEURAL
  TUBE WHICH WILL BECOME THE CNS
• NEURAL CREST CELLS FROM THE TOP OF THE NEURAL
  TUBE THAT FORM VARIOUS TISSUES, TEETH, BONES,
  SKULL, MUSCLES AND SKIN PIGMENTATION

18

• EMBRYONIC DEVELOPMENT
• AMPHIBIAN (FROG)
• GREY CRESCENT A REGION IN THE CYTOPLASM THAT
  EACH INDIVIDUAL CELL CAN DEVELOP INTO AN ENTIRE
  ORGANISM (IF IT CONTAINS A TINY PORTION OF THE
  GREY CRESCENT)
• GASTRULATION
• VENTRAL LIP LATERAL LIP BOTTOM AND SIDES OF
  THE BLASTOPORE
• DORSAL LIP TOP EDGE

19
(No Transcript)
20

• AVES BIRDS
• BLASTODISC REGION WHERE CLEAVAGE OCCURS, IT IS
  A FLATTENED DISC SHAPED REGION
• PRIMITIVE STREAK INVAGINATION OCCURS ALONG THIS
  LINE

21

• HUMANS
• BLASTOCYST BLASTULA STAGE THAT CONSISTS OF 2
  PARTS
• TROPHOBLAST THE OUTER RING OF CELLS WHICH
  EMBEDS INTO THE ENDOMETRIUM FOR IMPLANTATION.
  PRODUCES THE HORMONE HCG. WILL FORM THE CHORION
  WHICH EVENTUALLY BECOMES THE PLACENTA

22
(No Transcript)
23

• EMBRYONIC DISC
• ICM INNER CELL MASS
• FOUND WITHIN CAVITY CREATED BY THE TROPHOBLAST
• ANALOGOUS TO THE BLASTODISC IN BIRDS REPTILES
• PRIMITIVE STREAK DEVELOPS THAN GASTRULATION AND
  DEVELOPMENT OF THE EXTRAEMBRYONIC MEMBRANES
  (EXCEPT CHORION)

24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28

• CELL DEVELOPMENT
• DIFFERENTIATION
• EGG CYTOPLASM MAY INFLUENCE DEVELOPMENT
• EMBRYONIC INDUCTION ORGANIZERS, CELLS THAT
  INFLUENCE OTHER CELLS. CELL SIGNALING, CHEMICAL
  SECRETIONS. DORSAL LIP FUNCTIONS AS AN ORGANIZER
• HOMEOTIC GENES CONTROL DEVELOPMENT. TURN ON
  OFF OTHER GENES THAT CODE FOR SUBSTANCES THAT
  DIRECTLY EFFECT DEVELOPMENT
• HOMEOBOX 180 NUCLEOTIDE SEQUENCE THAT MAY
  IDENTIFY A PARTICULAR CLASS OF GENES THAT
  INFLUENCE DEVELOPMENT
• LINEAGE MAPS TRACING THE FATE OF CELLS