Answer:
a. Ed/eD
b. RF=0.12
Explanation:
The alleles for genes D/d and E/e are:
- D_: only on neck spikes
- dd: along back spikes
- E_: long spikes
- ee: short spikes
After testcrossing a double heterozygote (DdEe x ddee) there are 4 types of offspring, two of them much more abundant than the other two. The homozygous recessive parent can only produce <em>ed</em> gametes, so the phenotypes of the offspring depend on the gametes that the double heterozygous parent produced.
The offspring was:
- Ed/ed 79
- ed/ed 12
- ED/ed 10
- eD/ed 76
Total: 177
a) This result suggests that the genes are linked. Since recombination is a rare event, the most abundant phenotypes always come from the parental gametes, and the least abundant come from the recombinant gametes.
<u>Therefore, the genotype of the doube heterozygote parent was </u><u><em>Ed/eD</em></u><u>.</u>
b) Recombination frequency (RF) = Recombinants / Total
RF = (12+10)/177
<u>RF = 0.12</u>
Answer:
Reproduce, they use energy, and they produce waste.
Explanation:
Answer:
Plants harvest energy from the sun with the help of chlorophyll and carotenoid, two photon-capturing molecules. But if the plants are exposed to too much sun, these molecules absorb more energy than they can handle and generate reactive species of oxygen that can destroy the plant.
Answer: Option B (True)
Explanation: The statement can only occur in different populations of the same organism. The two growth strategies happens in different modes.
Firstly, logistic growth occurs when the resources available in the habitat (i.e organism’s niche) are limited to satisfy the whole population and this allows the organisms of the same species to grow rapidly until it reaches the point the resources can circulate, the carrying capacity.
While exponential growth occurs when there's abundance of resources for the population and allows growth of population beyond the carrying capacity, which results to overshoot of population in later stage of growth.
Secondly, in logistic growth population rarely crash but in exponential growth, population crashes due to mortality (often by predation, disease outbreak and etc) when there's overshoot of population beyond the carrying capacity.
Note: Population refers to the total number of organisms of the same species inhabiting a geographical area at a particular time.
Answer:
knirps (a gap gene)
wingless (a segment-polarity gene)
kruppel (a gap gene)
even-skipped ( a pair-rule gene)
hunchback (a gap gene)
hedgehog (a segment-polarity gene)
Explanation:
The gap, segment-polarity and pair-rule genes play central roles in controlling embryonic development of arthropods. In the first place, the gap genes are associated with the formation of contiguous body segments, thereby mutations in these genes result in gaps in the normal body plan of the embryo. For example, in <em>Drosophila melanogaster</em>, mutations in the <em>knirps, Krüppel </em>and<em> hunchback</em> genes result in deletion of body segments. These genes are also known to regulate segment polarity genes, which determine the polarity of the embryonic parasegments by modulating Wnt and Hedgehog signaling pathways. Finally, the pair-rule genes work together with gap genes to control embryonic development of alternating body segments.
