Download Sexual Reproduction - Winston Knoll Collegiate

SEXUAL REPRODUCTION
WHAT IS SEXUAL REPRODUCTION
• Sexual Reproduction in plants and animals is the union of
two sex cells, called gametes to produce a new
individual.
• Sex cells from females are called eggs or ova
• Sex cells from males are called sperm
• The union of the sperm cell with the egg cell is called
fertilization.
• Sexual reproduction produces offspring that have
some traits from one parent and some traits from the
other.
MEIOSIS
• Gametes (sperm and eggs) are produced through a cell
division process called Meiosis.
• Meiosis is very similar to mitosis and has very similar
steps but goes through the steps twice.
• Meiosis has two parts: Meiosis 1 and Meiosis 2
• Both parts have the same phases as mitosis in the same
order.
• Meiosis 1 does not produce cells with the same genetic
material- the chromosomes shake up and trade genetic
material.
• Meiosis 2 takes the mixed chromosomes and pulls them
apart making the final germ cells.
MITOSIS VS MEIOSIS
• Mitosis produces two daughter cells that are exact
copies and have the same number of chromosomes as
the parent cell
• Meiosis produces four daughter cells that have half
the number of chromosomes as the parent cell
• These gametes produced in meiosis only have half the
number of chromosomes because they then meet
another gamete and create a zygote with the other half
of chromosomes. This zygote becomes an embryo
(Baby)
HERMAPHRODITES
• A Hermaphrodite is an organism that can
produce both male and female reproductive
cells
• Some Hermaphrodites can reproduce sexually
with a partner or sexually by themselves
through a process called self fertilization
• Some can also change their sex to fit the needs
of their environment
SEXUAL REPRODUCTION IN PLANTS
• We know they do a lot of asexual reproduction with
spores and grafting but how does a plant sexually
reproduce?
• Plants have special parts for reproduction that serve
similar functions to sexual reproduction in animals.
• Video
• https://www.youtube.com/watch?v=YqM6rgB_l_o
• https://www.youtube.com/watch?v=2ycl2E9r-_o
• Self Pollination: occurs when the transfer
is within the same plant
• Cross Pollination: occurs when the pollen
of one plant is carried to the stigma of
another by wind, water, air or other
animals
WHY SEX?
• There are advantages and disadvantages to the
two reproductive strategies we have seen:
• Asexual Reproduction:
• Advantages?
• Disadvantages?
• Sexual Reproduction:
• Advantages?
• Disadvantages?
NOW YOUR TURN SCIENCE 9:
Read Text book Pages 27-34
Pg. 30 #1-4
Pg. 34 # 1, 3, 6, 8, 9, 11