REPRODUCTION:
PLANTS
ANIMALS
HUMANS
, INTRODUCTION TO PLANT REPRODUCTION
▪ REPRODUCTION is the ability of living organisms to produce a new
generation of themselves
▪ There are two natural forms of reproduction:
o Asexual and sexual
o “A” always means “non”
ASEXUAL REPRODUCTION SEXUAL REPRODUCTION
DEFINITION • The production of a new • The process involved in the
generation of the same species bringing together of a new
by one parent. generation of the same species
• No sexual intercourse by bringing together the
genetic material of two
parents.
NUMBER OF • One; all individuals can produce • Two, with 2 genders (male and
offspring female)
PARENTS
PROCESSES • One stage: mitosis (only one • Two stages; meiosis
parent organism divides itself (production of eggs and sperm
for reproduction, and the -> genetic material of parents
offspring has identical DNA) is split up) and fertilisation
GAMETE • No gametes (reproductive cells • Gametes formed
-> ova/eggs in females and
PRODUCTION
sperm in males) formed
END RESULT • Offspring genetically identical • Offspring genetically different
to the parent: no variation. because alleles are shuffled in
• Low possibility of evolution meiosis and fertilisation. High
because all DNA is exactly the possibility of evolution due to
same genotypic variation.
VALUE • In unchanging environment, • In changing unstable
well adapted individuals are environments, individuals can
preserved. adapt to new conditions. In
• Reproduction is possible where plants, seeds are formed-
there are no/few mates. these can be easily stored for
months/years until the planting
season.
RATE OF • Faster - all individuals can • Slower- half of the population
reproduce are males who do not produce
REPRODUCTION
offspring
,ENERGY INPUT • More efficient, no energy input • Less efficient, energy input is
needed needed to produce gametes,
find and court a mate
OUTSIDE • None • Pollinators necessary for
pollination
AGENTS
ADVANTAGES • All individuals can produce • Results in variation which is
offspring the basis of evolution (a
• it takes place quickly species has a better chance of
• produces exact copies of survival as the offspring could
parent organism, therefore adapt to new ecological
predictable outcome. It niches)
maintains the quality of the • Allows organisms to evolve/
species. form new species
• A favourable mutation can • may prevent spread of disease/
spread quickly genetically resistant
• Less energy is required
• No pollinators needed
DISADVANTAGES • No variation genetically (if • high expenditure of energy
environmental conditions • reproductive process is slow
change (e.g., new pest), the • unfavourable mutations/
entire population may be at risk) recessive genes may be
expressed
• outside agents may be needed
in plants to carry pollen or
seeds
,
PLANTS
ANIMALS
HUMANS
, INTRODUCTION TO PLANT REPRODUCTION
▪ REPRODUCTION is the ability of living organisms to produce a new
generation of themselves
▪ There are two natural forms of reproduction:
o Asexual and sexual
o “A” always means “non”
ASEXUAL REPRODUCTION SEXUAL REPRODUCTION
DEFINITION • The production of a new • The process involved in the
generation of the same species bringing together of a new
by one parent. generation of the same species
• No sexual intercourse by bringing together the
genetic material of two
parents.
NUMBER OF • One; all individuals can produce • Two, with 2 genders (male and
offspring female)
PARENTS
PROCESSES • One stage: mitosis (only one • Two stages; meiosis
parent organism divides itself (production of eggs and sperm
for reproduction, and the -> genetic material of parents
offspring has identical DNA) is split up) and fertilisation
GAMETE • No gametes (reproductive cells • Gametes formed
-> ova/eggs in females and
PRODUCTION
sperm in males) formed
END RESULT • Offspring genetically identical • Offspring genetically different
to the parent: no variation. because alleles are shuffled in
• Low possibility of evolution meiosis and fertilisation. High
because all DNA is exactly the possibility of evolution due to
same genotypic variation.
VALUE • In unchanging environment, • In changing unstable
well adapted individuals are environments, individuals can
preserved. adapt to new conditions. In
• Reproduction is possible where plants, seeds are formed-
there are no/few mates. these can be easily stored for
months/years until the planting
season.
RATE OF • Faster - all individuals can • Slower- half of the population
reproduce are males who do not produce
REPRODUCTION
offspring
,ENERGY INPUT • More efficient, no energy input • Less efficient, energy input is
needed needed to produce gametes,
find and court a mate
OUTSIDE • None • Pollinators necessary for
pollination
AGENTS
ADVANTAGES • All individuals can produce • Results in variation which is
offspring the basis of evolution (a
• it takes place quickly species has a better chance of
• produces exact copies of survival as the offspring could
parent organism, therefore adapt to new ecological
predictable outcome. It niches)
maintains the quality of the • Allows organisms to evolve/
species. form new species
• A favourable mutation can • may prevent spread of disease/
spread quickly genetically resistant
• Less energy is required
• No pollinators needed
DISADVANTAGES • No variation genetically (if • high expenditure of energy
environmental conditions • reproductive process is slow
change (e.g., new pest), the • unfavourable mutations/
entire population may be at risk) recessive genes may be
expressed
• outside agents may be needed
in plants to carry pollen or
seeds
,
