Download WHAT DO MATING ADULTS TRANSMIT TO OFFSPRING

WHAT DO MATING ADULTS
TRANSMIT TO OFFSPRING
Chapter 5
Early View
Mitosis & Meiosis
What was the Early View
•
HIPPOCRATES:
1. transmission of
particles or seeds
2. came from all
parts of body
3. acquired
characteristics
passed on
New Idea
• ARISTTOTLE:
1. Something must pass from parent
2. Must be located in reproductive
materials of both sexes
3. called semen
ARISTOTLE’S PROOF
• IF: particles came from all parts of both
parents’ body parts
AND: two adults mate & have a child
THEN: the child would have 2 heads, 4
arms, 4 legs etc.
BUT: that does not occur
ARISTOTLE’S PROOF
• IF: acquired characteristics were passed
on
And: leaves removed from parent plants
Then: offspring would have no leaves
BUT: the offspring do have leaves
He believed a set of instructions were
transmitted to guide development.
WHAT IS IN SEMEN?
• 1677: Anton van
Leewenhoek saw
sperm animals.
• 1854: George
Newport: do sperm
contain parasites or
heredity info.
• Frog egg experiment
1665 Robert Hooke
 Microsopic view of cork
 He called a “CELL”
 Dutrochet: all living things composed of
cells
 Schwann & Schleiden: cells are basic units
of life & basic functional units. Cytoplasm
contains variety of tiny structures of various
sizes and shapes.
1858 Rudolf Virchow
 Nucleus: leading candidate for heredity

information
 Organisms grow by producing new cells
Cell Theory
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