Asexual/sexual reproduction Flashcards
Genetic Diveristy
the amount of genetic variation that exists between individauls
Gene pool
The sum of differnet alleles present in a certain population
note in a gene pool”
the number of dominant alleles is 10/16
the number of recessive alleles is 6/16
What does it mean to have a larger gene pool/what is the advantage of this
Larger genetic diveristy
for exmaple, the population of cheetahs decreased during the ice age as tehey had a small gene pool so the cheetahs were forced to reporudce with thei relaitvives, this results in diseaes alleles being passed onto offpsirng ulitmaltey decreasing populatiom.
Importance of genetic diveirtiaisty
Ensures survival of species against changes to the environment and allows evoultion to be contious
What optimises the individulls chance of survivng to new change
having a larger gene pool
Natural selection
when factors such as the enviornmrent act of a population causing change to genetic diveristy
Sexual reproduction
the fusion of 2 gametes through fertilsiation
In sexual reproduction, how does genetic varation occur
genetic varation occurs due to the meiosis of gametes in sexual reproduction
What are reproductive strategies
adaptions to reproduce that improve the sucess of the sutvival of a specfies
examples of organisms that use reproductive strategies and how explain!
Male statin bowers- have a glossy blue-blakc plumage and build a decorative bower to attract females—they use their bower as a courtship arena
Brown male Antechnius-They live only 11 months and die from stress and exhausation following a 2 week breeding
Angiosperms(flowering plants)- Offer nectar, scents, colours and petals to attract pollinators to deliever pollen to the stigma of the flower to allow fertilsation and seeds production
what is internal fertilsiatoion
internal fertilsiation is where fertilisation occurs inside the body–this allows the young to be protected from predators
types of internal fertilisation(sexual reproduction)
- oviparity
- ovoviviparity
- viviparty
oviparity
the fertiilsed eggs are laid outside the bodt and the egg recievevs nourishment form the yolk eg. fish and birds
Ovoviviparity
The fertilised eggs are retained from the female and the embyro recieves nourishmetn from the yolk–when they hatch the young ones are fully developed
eg. lizards or snakes
Viviparty
the young develops inside the mother and recives nourishmenet throuhg the placneta
eg. most mmammels and cartilagonious fihs
evolution
a process that results in changes to genetic materila of a population over time
what is external fertilisation strategies
fertilsiaton occurs outside the body usually in water when the female releases an egg and the male releaes sperm into the same envornmrent causing fusion by chance.
it occurs in fish frogs and starfish
How are some gametees lost or destroyed
some gametes or lost or destroyed through predation
Advantages VS disadvantages of sexual reproduction
Advantages:
1.increases genetic diveristy of a population
2. greater chance of surviving new selection pressures such as disease
3. reduced chance of genetic disorders passed onto offspring
Disadvantages:
1. Time and energy to attract and find a mate
2. Tranferable disease due to sexual intercourse
3. Ineffiecnet due to many gametes not fertilsaied
Asexual reproduction
a single parent produces offpsring idenitcal to themsleves without the fusion of gametes
occursin both unicelluar and multicelluar orgnaims eg. fungi plants and bacteria
What are the 6 reproductive methods in asexual reproduction
- Binary fission
- Budding
- Fragmentation
- Vegegative propagation
- sporogenisis
- parthenongensis
What is binary fission
A fast process that occurs in prokaytoes like bacteria where one parent cell divides into 2 identical daughte rcells and the cell duplicates and elongates
Compare binary fission to mitosis
no spindle fibres or breaking down of nuclear memebrane in binary fission and mitosis takes a couple of daystheprocess whereas binary fission only takes a couple of minutes
Budding
A new smaller individual is produced from the outgrowth of the parent organism
occurs in hydra and yeast–note that the new orgnaism produced is smaller from the origninal one
Fragmentation
the breaking away of a piece of the parent organism to develop into a new and identical organism
eg. worms and sea staras
Vegative propagation
where roots, leaves and other parts break away from the plant and regrow into a new plant without seeds.
Sporogenisis what is, how are they easily spread, and what do they have they have the abilty to grow into
airborne mass asexuakreproduction of single structures that disperse in the surroudnings or these orgnaims
they are easily reproduced/ spread in moist and dark enviornremnts
spores have the abilty to grow into larger mutlicelluar organisms
occurs in bread
Parthenongeniiss
occurs when female indivuvdald lay an egg that may of not been fertilsied but go on to develop into complete organisms due to mitotici divisions of the egg cell. eg.bees
Advantages vs disavantages of asexual and sexaul reproduction
Advantages:
1. fast rate of reproduction and population increases in a short amount of time
- no need to find a mate
- does not require energy and time to take care of young
Disadvantages:
1. lack of genetic diveristy so suspectiabble to new selection pressures
2. clones are produced so diseases are passed onto offspring
Compare asexual and sexual reproduction
- sexual reproduction is the fusion of gametes to form a new organism whereas, asexual reproduction does not involve the fusion of gametes
- offpsring are geneticall diffenret to the parent in sexual whereas in asexuathey are genetical identical
3.proveis egentic diveritty in sexaul whreeas in aseuxal lacks genetic diveirist
- time required to find a mate to care for young in sexual vs aseuxal has rapid reproduction
NATURAL SELECTION IS THE MOST IMPORANT MECHANISM OF
EVOLUTION
what does natural selection do
creates genetic diversity in a population
genetic diverisyt is important in spciecies because
it is neessceaysr for evolution to take place
genetic variation reproducing species occurs as a result of
mutation
why does premature aging occur in cloning
telomerse shrink as organisms get older, but as the clones have the same chromsomes of an adult parent orgnaism, that parent organisms telomeres would already have shrunk as it is an adult and this clone produced is identical to that parent orgnaism so likewise its telomeres will alos shrink reulsting in premature aging and have rhe samelife exptenacyof ht eparne t organism
advantages vs disavnatages of sexual reproduction
advantages:
1. more gentic diieryst
2. greaterchance ofsurivival if new sleection pressures are present
3.reduced genetic disorders are passed on
Disadvantages:
1. requrire smore time and energyto find a mate
2. dieases like stds
3. wastde gametes posisbly duirng external fertilsiation
what is grafting
involves attaching the stem of one plant to the stem of another plant on an already developed root system
how does grafting cause encomcicn beneift ot the farmers
less time for the plant to develop and produce fruit as the plant has a mature root system
