Reproduction Flashcards
What are the two types of reproduction?
Asexual and Sexual
What is Asexual reproduction?
A mode of reproduction that an organism can replicate itself without another organism
What is sexual reproduction?
A mode of reproduction involving the fusion of one haploid gamete with another haploid gamete to create a diploid zygote
What are the types of asexual reproduction?
fission, budding, fragmentation,vegetative propagation,spore formation,parthenogenesis
What are the types of sexual reproduction
Dioecious vs monoecious,internal vs external fertilization, oviparous vs viviparous,few offspring vs many offspring
Asexual vs sexual reproduction
Requires only one parent organism ,Requires two parent organisms
Offspring are genetically identical to parent, therefore diseases are passed on and adapting to new conditions (i.e. evolution) is very slow
Produces genetic variation in offspring, therefore the species is more able to adapt to different environments or a population may be more resistant to disease
Time and energy efficient, e.g. don’t need to, Requires more time and energy, e.g. need to find a mate find a mate
The population can increase rapidly when conditions are good,Generally much slower because more conditions are good time/energy required and only half the
population can reproduce
What is fission and what are the two types of fission?
Fission is found in all Domains and all Kingdoms of life
(Bacteria, Archaea, Protista, Fungi, Plantae, Animalia).
• Occurs in unicellular and multicellular organisms.
• A parent cell or organism divides itself into equal parts.
1) Binary fission results in two cells or organisms (common in Bacteria and Archaea).
2) Multiple fission results in more than two cells (common in Protista).
What is budding?
Budding is found in all Domains and all Kingdoms of life
(Bacteria, Archaea, Protista, Fungi, Plantae, Animalia).
• Occurs in unicellular and multicellular organisms.
• A parent cell or organism divides itself into two unequal parts.
• A small bud (outgrowth) forms on the parent cell or organism and breaks off to form a new daughter cell or organism.
What is fragmentation?
Fragmentation is found in all Eukaryote Kingdoms of life
(Protista, Fungi, Plantae, Animalia).
• Occurs in multicellular organisms.
• Fragments of an organism can break off and then become into a new organism.
What is vegetative propagation?
Vegetative propagation is found in one
Eukaryote Kingdom of life (Plantae).
• Occurs in multicellular organisms.
• Where a new plant grows from a fragment of the parent plant.
• Many different strategies, such as: • runners
• bulbs • tubers
• suckers/basal shoots/root sprouts
What is parthenogenesis?
Parthenogenesis is found in the Eukaryote Kingdom of
Animalia.
• Occurs in multicellular organisms.
• An unfertilized egg develops into an individual.
• Occurs in water fleas, wasps, bees, ants and some fish and lizards.
• Most organisms that reproduce by parthenogenesis can also reproduce sexually.
What is polyploidy ?
Heritable condition of having more than two complete sets of chromosomes.
Common in plants, and found in some fish, amphibians and worms.
Arises from an error in mitosis or meiosis. Can lead to speciation.
What is alternation of generations?
Alternation of generations is found in many multicellular protists, all land plants and some fungi.
Both the haploid and diploid forms are multicellular.
The diploid form gives rise to spores and the haploid form gives rise to gametes.
Internal fertilization vs external fertilization
Terrestrial and aquatic
• Generally motile because
need to find a partner
• Can be selective over who
fertilises egg
• Many behaviours/
adaptations to choose partner and compete with rivals
• Aquatic only
• Useful for sessile
organisms
• Requires behaviours/
adaptions to ensure
gametes meet
• Often limited control over
whose gamete fertilises egg
Oviparous vs Viviparous
Egg laying
Embryos develop externally
Nutrients for development are in the egg
Shell protects embryo and impedes water loss
Live young
• Embryos develop internally • Nutrients from mother
• Mother’s body protect embryo.
