chapter 20 - mitosis and asexual reproduction

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
WHAT ARE ALL THE LIFE PROCESSES?
› H.N.T.R.S.G.E.R.M.R

WHICH ONES HAVE WE COVERED?
› H.N.T.R.S.G.E.R.M

WHAT’S LEFT?
› R  REPRODUCTION!!

WHAT IS REPRODUCTION?

REPRODUCTION
› THE PROCESS BY WHICH LIVING THINGS
PRODUCE NEW ORGANISMS OF THEIR OWN
KIND

HOW DOES REPRODUCTION WORK?
› REMEMBER:
ALL CELLS ARISE FROM PRE-EXISTING CELLS
› THE PROCESS BY WHICH CELLS MAKE MORE
CELLS IS CALLED…
›CELL DIVISION

CELL DIVISION CAN BE BROKEN INTO
TWO CATEGORIES
› MITOTIC CELL DIVISION EXACT COPIES ARE
MADE
› MEIOTIC CELL DIVISION NOT EXACT COPIES
ARE MADE
 *WE WILL DISCUSS THIS ONE FURTHER NEXT
CHAPTER*

MITOTIC CELL DIVISON
› CLICK THE PIC
FOR THE
CELL DIVISION
SONG

MITOTIC CELL DIVISION
› A.K.A. ASEXUAL REPRODUCTION
 REPRODUCTION WITHOUT SEX (REQUIRING
ONLY ONE PARENT CELL)
› BROKEN INTO TWO PROCESSES
 MITOSIS
 CYTOKINESIS

MITOSIS

MITOSIS
› THE CONTENTS OF THE
NUCLEUS ARE COPIED
AND THEN DIVIDED TO
FORM TWO IDENTICAL
NUCLEI
› WHY IS THIS SO IMPORTANT? IN OTHER
WORDS, WHY DOES THIS NEED TO HAPPEN?
(*HINT – WHAT’S IN THE NUCLEUS?)

MITOSIS
› LET’S BREAK
DOWN THE
STAGES OF
MITOSIS
› CLICK THE
IMAGE FOR A
VIDEO

CYTOKINESIS
› THE CYTOPLASM (CELL) DIVIDES IN TWO

CYTOKINESIS
› IN ANIMAL CELLS
 CLEAVAGE FURROW
› IN PLANT CELLS
 CELL PLATE FORMATION

WHY IS THERE A DIFFERENCE WITH
CYTOKINESIS AND NOT WITH MITOSIS?
SHOULD MITOTIC CELL DIVISION HAPPEN
ALL THE TIME? WHY OR WHY NOT?
 SHOULD MITOTIC CELL DIVISION HAPPEN
AT THE SAME RATE ALL THE TIME? WHY
OR WHY NOT?
 WHAT DO WE CALL MECHANISMS THAT
CAN CHANGE THE RATE OF A
REACTION?
(*HINT  WHAT CONTROLS INSULIN
PRODUCTION?


WHAT’S A CONSEQUENCE OF MITOTIC
CELL DIVISION HAPPENING
UNCONTROLLABLY?
C
A
N
C
E
R

DON’T WORRY…NORMALLY A SPECIAL
PROTEIN CALLED CYCLIN EXISTS THAT
CONTROLS WHEN CELLS DIVIDE, SO THE
“C” WORD IS KEPT IN CHECK

MITOTIC CELL DIVISION AS A FORM OF
REPRODUCTION
› ASEXUAL ONLY
› PRODUCES “IDENTICAL” OFFSPRING

FORMS OF ASEXUAL REPRODUCTION
›
›
›
›
›
BINARY FISSION
BUDDING
SPORE FORMATION
REGENERATION
VEGETATIVE REPRODUCTION
(PROPAGATION)

BINARY FISSION

BUDDING

SPORE FORMATION

REGENERATION

VEGETATIVE PROPAGATION

THAT’S MITOTIC CELL DIVISION…BUT
WHAT IF YOU DON’T WANT AN
“IDENTICAL” OFFSPRING?

PRESENTING MEIOTIC CELL
DIVISION…COMING NEXT CHAPTER 
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