On a blank piece of paper, write down everything that is in RED.

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On a blank piece of paper, write down everything
that is in RED. On your textbook, look under
asexual reproduction, and sexual reproduction
on the index and read pages listed.
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Methods of Reproduction Sexual and Asexual
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• Asexual Reproduction
• requires only 1 parent
• offspring are exact copy of the parent a clone
• No genetic variety in the population organisms
  are copies of the original.

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Types of asexual reproduction

• Binary fission
• Budding
• Fragmentation/Regeneration
• Spore formation
• Parthenogenesis
• Assexual rep. 2.4 min

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Binary fission

• divide into two equal halves
• Single cell organisms
• examples Amoeba, paramecium, euglena
• binary fission bacteria

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• When conditions are good, such as plenty of
  water, food, right temperatures, etc., binary
  fission is a very effective way of producing
  many, many offspring.
• For example, the cell of a Paramecium can divide,
  grow, and divide again in the space of 8 hours.

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Budding

• an offspring grows out of the body of the parent.
• Offspring smaller than parent cell budding
  yeast

offspring
yeast
Cactus Budding
Hydra Budding
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Fragmentation/Regeneration

• piece of parent organism produce an offspring.
• Plant cuttings Some plants can grow from cutting
  them up and replanting them.
• coral reproduction

Pieces of coral broken off in storms can grow
into new colonies.
A new starfish can grow from one detached arm.
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• Green plants are quite sophisticated in their
  methods of asexual reproduction. Offspring may be
  produced by runners, bulbs, rhizomes or tubers.

runners
Suckers/buds
tubers
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Spore Formation

• spores grow into multicellular individuals
• Examples Algae, fungi
• mushroom spores

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Parthenogenesis (natural cloning)

• Eggs develop without fertilization.
• Examples invertebrates, several fish,
  amphibians, reptiles, many plants.
• no known cases of parthenogenesis in mammals.
• comodo dragon

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Sexual Reproduction

• Needs 2 parents
• male and female
• Gametes (sex cells egg and sperm)
• Egg joins sperm to form zygote (new organism)
• Offspring are different from parent
• Diversity because of exchange of genetic material
  in meiosis
• Genetic variation improves survival (evolution)

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Sexual Reproduction
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Types of sexual reproduction

• Pollination
• External Fertilization
• Internal Fertilization/Copulation
• Hermaphroditism

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Pollination

• pollen attaches to female egg, found in stigma.
• Pollen is male sex cells in plants. Found in
  flowers anthers.

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External Fertilization

• requires a medium (water) sperms swim to the egg
  cell.
• fish and amphibians
• females lay the eggs in the water and the male
  squirts the sperm in the same area.
• oscar fish
• oscar fry

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Internal Fertilization

• Fertilization occurs within the female.
• mammals, insects, birds, reptiles.
• Mammals have live births
• Insects, birds, reptiles, lay eggs

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Hermaphroditism

• organisms have both reproductive organs
  ovarian and testicular tissue
• Example snails, starfish, sand dollar, worms,
  seahorses, grouper, sea bass

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Sexual vs. Asexual Reproduction

• Asexual
• Mitosis generates cells
• Somatic cells (ex. skin cells) or unicellular
  organisms
• offspring that are genetically identical to the
  parent
• Needs 1 parent.
• Sexual
• Meiosis generates sex cells
• Sex cells or gametes (sperm and egg)
• offspring is genetically different from parent
• Needs 2 parents (male and female)

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Asexual Reproduction Advantages 1. large
number of offspring 2. less energy 3. No sex
organs or opposite sex partners
Disadvantages 1. No genetic variation 2. Less
likely to survive changes in environment
(evolution) 3. No protection of young decreases
survival
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Sexual Reproduction Advantages 1. genetic
diversity 2. More chances to survive changes in
environment (evolve) 3. Caring for young
increases survival Disadvantages 1. reproduce
less frequently have fewer offspring 2. More
energy to protect and nurture offspring 3.
Non-nurturers leave offspring vulnerable to
predators