Sexual and Asexual Reproduction Flashcards
Characteristics that can be passed from one generation to the next through genes are…
hereditary
What is reproduction?
the production of new organisms (offspring) through sexual or asexual mean
What are the two main categories of reproduction?
sexual and asexual
What does sexual reproduction require?
two individuals/parents, whose genetic information is combined
What does asexual reproduction require?
one individual parent
What kind of offspring are produced through sexual reproduction?
genetically unique offspring
What kind of offspring are produced through asexual reproduction?
genetically identical, clones
What is required for the offspring produced by asexual reproduction to be identical to their parents
the same environment
What is a zygote?
a fertilised egg cell
Zygotes are produced from…?
the sex cells of both parents
What are the sex cells of mammals?
sperm for males, ovum for females
What is the main advantage of sexual reproduction and why is this an advantage?
increase genetic diversity, meaning the population becomes more likely to adapt in response to change
What are the main disadvantages of sexual reproduction?
takes more time, energy and resources than asexual reproduction
What are the main advantages of asexual reproduction?
faster and more efficient
What is the main disadvantage of asexual reproduction?
reduces genetic diversity
What’s a real-life example of asexual reproduction reducing genetic diversity?
the Irish Potato Famine, where potato plants had a very low genetic diversity because they basically all originated from cuttings of the same plant. So when a fungal disease hit them, they were all so genetically identical, that they all got identically sick, and were killed
What is a real life example of sexual reproduction increasing genetic diversity?
the Galapagos Finches
What are the two main categories of sexual reproduction in animals?
external and internal
What is external fertilisation?
both the male and female release their sex cell into their environment , so the egg is fertilised outside the body
What is internal fertilisation?
where the egg is fertilised inside the body
What kind of animals usually reproduce internally?
dry, land-based animals like mammals, reptiles and birds
What kind of animals usually reproduce externally?
fish and amphibians
What are two advantages of external fertilisation?
1) because fertilisation happens outside the female body, there isn’t a limitation of space. So many more offspring can be made because more sex cells can be released and grown
2) the parents don’t actually have to meet. So saves lots of time and energy
What are two disadvantages of external fertilisation?
1) with the parents not around, any fertilised offspring have a way smaller chance of actually surviving. With no parent to protect or feed them, they are basically at the mercy of predators and violent weathers
2) the sex cells might not even have a chance to be fertilised and become offspring before they are destroyed. Actually this happens the majority of the time. So waste of resources
What are two advantages of internal fertilisation?
1) offspring have a much higher chance of survival because they are protected by the female’s body.
2) making less sex cells saves time, energy and resources, which is easier on the parent
What are two disadvantages of internal fertilisation?
1) only a few offspring can be produced at a time. As the whole point of reproduction is to carry on genes and survive, this is risky
2) parents have to physically meet and mate. So extra time, energy and effort
What’s an example of animals that produce sexually and asexually?
komodo dragons
What is the method of reproduction called where animals produce young asexually?
parthenogenesis
How do plants reproduce (asexually or sexually)?
both
How do plants reproduce asexually?
- runners
- bulbs
- cuttings + graftings
Runners, bulbs, buddings, cuttings and grafting are what methods of reproduction?
asexual plant reproductions
What are runners?
roots that grow out of the side of another grown plant and above + along the ground, settling down nearby to develop into a mini plant or plantlet
What kind of plant reproduces with runners?
strawberry
What are bulbs?
where baby plants or buds grow up and out of “bulbs” underground that are connected to a mother plant’s roots
What are cuttings?
a person cuts a branch from the parent plant, and grows it in doil or water till it develops roots, stems and leaves and grows fully into an adult plant
What is grafting?
A cutting from the stem of the plant is bound to the cut stem of another plant with developed roots. The stems fuse, and the grafting grows as if it is part of the original plant
What is another word for cuttings?
vegetative propagation
What makes cutting and grafting different to runners and bulbs?
they are unnatural. Humans have to do it
What is budding?
a section of the parent plant breaks off, forming an independent individual
What kind of plants reproduce with bulbs?
tulips and daffodils
