Antonie van Leeuwenhoek
1632-1723
Developed
microscopes for
observing living
organisms
1674 discovered
protists
1677 discovered
spermatozoa
1682 discovered
striated muscle
fibers
http://www.cartage.org.lb/en/themes/Sciences/Physics/Optics/OpticalInst
ruments/Microscope/GlassSphere/usph_01.gif
http://www.molecularexpressions.com/primer/images/introduction/leeuwenhoek.jpg
http://students.ou.edu/J/Renee.E.Jones-1/Van%20leeuwenhoek%20Scope.jpg
http://cell.sio2.be/introduction/images/microleeuw.jpg
Schematic Human Sperm Cell
http://academic.evergreen.edu/v/vivianoc/homunculus.gif
Homunculus
Human (Homo sapiens) Sperm Photograph
Mammalian Syngamy: Plasmogamy
Calcium release spreading across an egg cell during syngamy
Amphioxus (lancelet) adult, zygote, and early cleavage
not to scale!
Amphioxus (lancelet) cleavage
Amphioxus (lancelet) gastrulation and adult
not to scale!
Morphogenetic movements of cells during development
Amphioxus (lancelet) nerulation
Origin of some mammalian tissues or organs
Primary Tissue Layer
Tissue or Organ
Ectoderm Mesoderm Endoderm
Epidermis
Muscle
Lungs
Hair
Bone
Liver
Nails
Blood
Pancreas
Notochord
Digestive
lining
Kidneys
Bladder
Eye lens
Nerve
system
Nasal oral
mucosae
Gonads
Frog (Rana pipiens) embryology
Frog (Rana pipiens) zygote
Frog (Rana pipiens) embryo: early cleavage
Frog (Rana pipiens) embryo: later cleavage
Chicken (Gallus gallus) zygote and early cleavage
blastodisc
yolk
Chicken (Gallus gallus) gastrulation
Chicken (Gallus gallus) embryo after 4 days of incubation
Human (Homo sapiens) embryo
Human (Homo sapiens) embryo
Human (Homo sapiens) embryo
Human (Homo sapiens) embryo
Comparison of vertebrate embryos of six species at 3 stages
Ontogeny recapitulates Phylogeny
Typical sigmoid (S-shaped) growth curve: logistic curve
Weight
plateau phase
lag phase
Age
Weight growth in a mouse (Mus musculus)
Puberty
16
Weight in grams
14
12
10
8
Weaning
6
http://www.c-wilkie.pwp.blueyonder.co.uk/jokes/images/mouse_sex.gif
4
2
5
http://www.sasionline.org/antsfiles/articles/images/Dino/mouse.jpg
10
15 20 25 30 35 40 45
Days after birth
Weight growth in an insect (Malanoplus) with 5 molts
adult
Sudden increase
when body lacks
exoskeleton
(soft shell crab)
Weight (mg)
150
100
Nymphal instars:
50
5
4
1
zygote
0
2
3
20
40
Age in days
60
How does weight increase suddenly when not feeding?
Multiples of weight at birth
Differential growth in weight of the Homo sapiens body and its parts
20
Body
Why does the
curve inflect
here?
15
Does growth
continue
indefinitely?
Heart
10
Brain
5
0
5
10
15
Age in years
20
Average decline in a Homo sapiens from age 30 to 75 years
Characteristic
Percent Decline
Weight of brain
44
Number of nerve cells in spinal cord
37
Velocity of nerve impulse
10
Number of taste buds
64
Blood supply to brain
20
Output of heart at rest
30
Speed of return to normal pH of blood after
displacement
83
Number of filtering subunits in kidney
44
Filtration rate of kidney
31
Capacity of lungs
44
Maximum O2 uptake during exercise
60
bipinnaria
http://www.cbu.edu/~aross/embryo/s-gastrula-2.jpg
brachiolaria
http://alpha2.bigelow.org/mitzi/images/library/subtidal%20ani
mals/Sub-An-B_039.jpg
planktonic
larvae
http://instruct1.cit.cornell.edu/courses/biog105/labs/deuts/media/echinowatervasc.jpg
http://micro.magnet.fsu.edu/optics/olympusmicd/gallerie
s/brightfield/images/starfishbrachiolarialarva.jpg
http://www.snv.jussieu.fr/bmedia/oursinMDC/coursours3/bipinn2leg.gif
Three larval stages and a sea star adult (Asterias vulgaris)
gastrula
benthic adult
Monarch butterfly complete metamorphosis: zygote (“egg”)
http://www.monarchwatch.org/update/2003/egg_glue1.jpg
Danaus plexippus
Monarch butterfly complete metamorphosis: larva
Danaus plexippus
Monarch butterfly complete metamorphosis: larva
Danaus plexippus
Monarch butterfly complete metamorphosis: larva
Danaus plexippus
Monarch butterfly complete metamorphosis: pupa
Danaus plexippus
Monarch butterfly complete metamorphosis: adult
Danaus plexippus
Monarch butterfly complete metamorphosis: adult
Danaus plexippus
Incomplete
(gradual)
metamorphosis in
grasshoppers
Brachystola magna
http://www.ent.iastate.edu/images/orthoptera/lubber.jpg
zygote
Life span in years (log scale)
Relative DNA repair rate among mammals
100
(Homo sapiens) Human
(Loxodonta africana) Elephant
(Bos taurus) Cattle
10
Hamster (Mesocricetus auratus)
Rat (Rattus norvegicus)
1
Mouse (Mus musculus)
Shrew (Suncus murinus)
Relative rate of DNA repair