Answer:
A. selective pressures that favor certain individuals
Explanation:
Answer:
3. B, D
Explanation:
A primary source is an animal that eats only plants. (herbivore) A secondary source is an animal that only eats herbivores (carnivores)
B has birds; which are food for carnivores, and fruits, nuts, and blossoms; which are food for herbivores.
D has vegetables and grains; which are food for herbivores, and meat; which is food for carnivores
The other options have only food for carnivores, or only food for herbivores, so the answer is 3
Answer:
The recombination frequency between two genes exhibits a positive correlation with the distance between them, that is, farther they are, and more will be the chance of recombination. Thus, recombination frequency is used to signify distance among the two genes, for example, 1 percent recombination frequency demonstrates distance of 1 map unit.
Let us consider that the heterozygous female of genotype AaBb can generate four kinds of gametes, that is, AB, Ab, aB and ab. Of these, the two gametes are the outcomes of recombination, or it can be said that 50 percent are recombinants. Thus, it can be concluded that in case of two linked genes, the maximum probable recombination frequency is 50 percent.
This shows that any genes, which are distant than 50 map units will function as unlinked and will function as if they were on distinct chromosomes, and the frequency of recombinant frequency will be 50 percent.
In the given question, it is given that the map distance between the two genes is 80 map units, that is, more than 50 map units. The maximum probable recombinant offspring will be 50 percent of the entire offspring.
Answer:
Horizontal gene transfer
Explanation:
Horizontal gene transfer or lateral gene transfer is when an organisms of different species can acquire a gene from a different one. This process is well understood in bacteria and is responsible for the appearence of antibiotic resistant bacteria. Bacteria can take DNA fragments through a process known as transformation, but this is less common in eukaryotes. Gene transfer agents like viruses could carry the gene from one specimen to the other. Another way could be Horizontal transposon transfer but the exact mechanisms behind it are still under research.
There are seven plate tectonics on Earth.
