AP Biology
Genetics and Development
ZYGOTE
Fertilized egg of a frog
Specialized Epithelial tissue
See the DIFFERENT shapes?
Specialization
Nervous Tissue
Morphogenesis over time
Animal development
Cell
movement
Zygote
(fertilized egg)
Eight cells
Blastula
(cross section)
Gut
Gastrula
(cross section)
Adult animal
(sea star)
Cell division
Morphogenesis
Observable cell differentiation
Seed
leaves
Plant development
Zygote
(fertilized egg)
Two cells
Shoot
apical
meristem
Root
apical
meristem
Embryo
inside seed
Plant
Apoptosis
“Programmed Cell Death… it’s in the DNA.”
Morphogenesis in Plants
Morphogenesis in Animals
Cloning of Dolly
Mammary
cell donor
Egg cell
donor
Egg cell
from ovary
Cultured
mammary cells
are semistarved,
arresting the cell
cycle and causing
dedifferentiation
Nucleus
removed
Cells fused
Nucleus from
mammary cell
Grown in culture
Early embryo
Implanted in uterus
of a third sheep
Surrogate
mother
Embryonic
development
Lamb (“Dolly”) genetically identical
to mammary cell donor
Embryonic Stem Cells
(These have pluripotential – they
can become any type of cell.)
LE 21-9
Embryonic stem cells
Adult stem cells
Totipotent
cells
Pluripotent
cells
Cultured
stem cells
Different
culture
conditions
Different
types of
differentiated
cells
Liver cells
Nerve cells
Blood cells
Pattern Formation for Plants
Pattern Formation
Pattern Formation
Positional Information
Maternal Effect and
Zygote Polarity
Point of
sperm entry
Animal
hemisphere
Vegetal
hemisphere
Animal pole
Vegetal pole
.
Sperm
Molecules of a
cytoplasmic
determinant
Unfertilized egg cell
Molecules of another
cytoplasmic determinant
Nucleus
Fertilization
Zygote
(fertilized egg)
Mitotic cell division
Two-celled
embryo
Cytoplasmic determinants in the egg
.
Early embryo
(32 cells)
NUCLEUS
Signal
transduction
pathway
Signal
receptor
Signal
molecule
(inducer)
Stem cells communicating using ligand molecules
Segment Genes
Adult
fruit fly
Fruit fly embryo
(10 hours)
Fly
chromosome
Mouse
chromosomes
Mouse embryo
(12 days)
Adult mouse
Hox Genes