Unit 9 #2 - Genes in populations Flashcards
Name 2 heterozygote advantage examples
Manx cats (Mm) have no tail, are therefore loved by humans and are deliberately breeded
In humans, Hh have normal haemoglobin, but are also resistant to malaria becasue in low O2 environment, the haemoglobin molecules stick together and change shapes which prevents plasmodium from eating them and thereby living
What is Hybrid Vigour
High levels of heterozygousity, which improves health and adaptability eg. DLS sheep
What is a consequence of isolation for populations?
No competition for food, no predators
What usually physically occur to isolated populations
- Get smaller eg dwarf elephants or Homo Floresiensis
- Get bigger: “dodo” pigeon
What does increase homozygousity in populations due to inbreeding lead to?
more parasites, and selection occurs to rectify by increasing heterozygousity
What is the effect of hunting on sheep phenotype?
Increase horn size
What is a population
groups of individuals of the same species that
live together in the same space and time.
What is a range
Where a population is, it can change (expand or contract)
What is dispersion
How a population is distributed throughout the range
What is density
Number of individuals in an area
Why do Wood frog and Leopard frog breed together
mating period overlap because of climate change
What are abiotic factors
elements of an environment that affect a population: temperature, sunlight, soil, water (+nutrients and heterogeneity)
What are biotic factors
Elements of an environment that affect populations: competitors (intra and interspecific), predators, diseases and parasites
What is the difference between interspecific and intraspecific competitors
Interspecific: competitors that compete for space, nutrients and other things with other species
Intraspecific: competitors that compete for space, nutrients and other things within a same species
What is adaptation
Gene pool of a population changes over time. I fact, those that maintain best homeostasis transmit their genes to the next generation. This causes evolution
