Replication/ reproduction. one side copies then replicates and matches up. hope this helps
Difference # Open Store System:
1. There is no specific storage area. Stores are maintained in the form of Suitable/convenient locations.
2. Every individual has access to anystorage facility.
3. After the receipt of the material it is delivered to respective department to expedite the production activity.
4. Chances of Pilferage high.5. Less emphasis on accounting control of the material.
Difference # Closed Store System:
1. All materials are stored in a closed/controlled area.2. No other person than the stores personnel is permitted in the area.
Materials can leave or enter the storage area only by authorised documents.
4. Maximum Physical Security.
5. Tight accounting control of inventory material.
Roots and leaves
The major driving force of water uptake in a large tree is transpiration.Transpiration is the process by which plants absorb water through the roots and release it as water vapor through the pores in their leaves. Once this water evaporates, a negative water vapor pressure is created or develops in the surrounding cells of the leaf. when this happens, water is pulled into the leaf from the vascular system, the xylem, to replace the water that has been transpired from the leaf.This pulling of water, or tension, that occurs in the leaf, will extend through the rest of the xylem column of the tree right into the xylem of the roots as result of the cohesive force holding the water molecules along the sides of the xylem tubing.The xylem is a continuous water column extending from the roots to the leaves.<span>Finally, the negative water pressure that occurs even to the roots will result in an increase of water uptake from the soil.</span>
The first step of DNA replication is the separation of the two DNA strands to create a replication bubble. DNA Helicase is what breaks the hydrogen bonds joining the two strands, allowing it to unravel.
Question: Does geographic distance between salamander populations increase their reproductive isolation? To answer this question, researchers studied populations of the dusky salamander (Desmognathus ochrophaeus) living on different mountain ranges in the southern Appalachian Mountains. The researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. Four mating combinations were tested for each pair of populations (A and B)—two within the same population (female A with male A and female B with male B) and two between populations (female A with male B and female B with male A). The proportion of successful matings for each mating combination was measured. For example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. Then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). The reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (AA + BB) minus the sum of the proportion of successful matings of each type between populations (AB + BA).
The table (Figure 1) provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.
Part A - Understanding experimental design
What hypothesis did the researchers test in this study?
Answer:
"Reproductive isolation increases with geographic distance between dusky salamander populations"
Explanation:
The mechanisms of reproductive isolation are a assemblage of evolutionary mechanisms, behaviors and physiological procedures dangerous for speciation. They avert followers of dissimilar types from manufacturing offspring, or confirm that any offspring are germ-free. While in allopatric speciation the reproductive isolation is resolute superficially by the spatial isolation of populations, during sympatric speciation specific groups of persons create distinct mating organizations with self-like persons while distribution the similar home with the rest of the unique inhabitants.
