http://www.hhmi.org/biointeractiv
e/gender/animations.html
Click meiosis
Shows crossing over, fertilization,
maturing embryo
Crossing Over
• Mom and Dad chromosomes switch parts
(this is a way of “changing it up”)
• Other mutations can also occur during
meiosis to create genetic diversity
(insertions, deletions, point mutations)
CENTERS!
Review Mitosis and Meiosis
• Side by Side
http://www.teachersdomain.org/resources/td
c02/sci/life/gen/mitosis/index.html
Sexual Reproduction
• Meiosis gives you gametes
• 2 individuals donate genetic material
• Mixes it up 
• Babies look a little like mommy and a little
like daddy but ARE NOT CLONES
http://www.jcb.org/cgi/content/full/
153/6/1209/DC1
Look at #1 and #5
Two Types of Sexual Reproduction
• Internal – fertilization occurs INside the
female
sharks
tigers
lizards
• External – fertilization occurs OUTside the
female
salmon
Asexual Reproduction
• Only one individual contributes genetic
material
• Mitosis
• Creates an exact copy of the individual
AKA A CLONE!
Examples
• Yeast = Budding
• Hydra = Budding
• Bacteria = Budding or fission
(because more equal in
size)
Planarians (flat worms)
Their whole body breaks
into pieces, each of
which can create a
new individual
Called Fragmentation
Bacteria sometimes do
this too!
Break off a little piece,
which can become a new
individual
Rooting/Cuttings in garden
terms
Regeneration in scientific
terms
Enchinoderms (starfish) do
this too!
Virgin Birth
• Parthenos = virgin
• Genesis = birth
• PARTHENOGENESIS
Rock Lizard
Aphids
Whiptails
http://www.teachersdomain.org/resources/tdc02/sci/life/repro/asexual/index.html