Complete question:
Categorize the following situation as either a pre- or postzygotic isolating mechanism and then specify which type of pre- or postzygotic isolating mechanism it is.
A short hike through the Sandia Mountains from early spring to late summer will often reveal several different species of penstemon. The Rocky Mountain Penstemon blooms in the spring while the very similar inflated penstemon blooms in late summer. As a result, hybrids are rarely encountered.
Answer:
- pre-zygotic isolating mechanism
- Type: seasonal or temporal
Explanation:
There are different mechanisms of reproductive isolation. These are barriers that inhibit or interrupt the genetic flux between different species. These mechanisms are about the biological characters of each species that prevent the reproduction with other species.
The reproductive isolation mechanisms might be either prezygotic or postzygotic.
-
Pre-copulatory or pre-zygotic:
- Ecological or due to habitat isolation;
- seasonal or temporal;
- Sexual or ethologic;
- Mechanical;
- Gamete incompatibility.
2. Post-copulatory o post-zygotic:
- Hybrid inviability
- Hybrid sterility
- Hybrid with diminished viability and or fertility
- Cytoplasmatic interactions.
The exposed situation is an example of prezygotic isolation due to seasonal or temporal barriers. Penstemon blooms in the spring, while the very similar inflated penstemon blooms in late summer. <em>Probably, if they had the same reproductive season, they would produce hybrids</em>. But as they are isolated by different reproductive seasons, they do not. <em>As they can not even fertilize, they are considered to be prezygotic isolated species. </em>
Answer:
Explanation:
time management:
pros- gets more things done in a timely manner.
cons- more planning and time consuming.
note taking:
pros- memorization technique, skills, penmanship.
cons- boring, time consuming, effort.
doing advanced readings:
pros- challenges you, gets you better.
cons- can be hard and frustrating.
listening actively:
pros- hear everything the other person is saying.
cons- can get annoying or dont have the time.
managing distractions:
pros- get to focus, set time aside to do something specific.
cons- dont want to do it, takes time away from you doing something else you want to do.
B. Proteins are constructed from amino acids
Primary succession is a process of forming ecosystems in an area that has never been inhabited before. Since living organisms are necessary for forming the soil, which is a foundation of every land ecosystem, at the point before the soil formation or pedogenesis has occurred the ecosystem provides very few habitats.
This would be a point mutation (and could be the change of 1 or 2 nucleotides in one codon that results in a different amino acid being called for). This ends up in a missense mutation.
