Answer:
The correct answer is C).
Explanation:
The genetic information that is encoded in a cell flows in the sense DNA, RNA and then the translation into proteins (amino acid sequence), which is stated by the genetic code. This states the relationship between the sequences of three nucleotides (codons), and amino acids. For each codon corresponds to a specific amino acid. Ex: AAG codes for Alanina.
Answer:
1
Explanation:
During meiosis, a diploid cell ultimately forms four haploid gametes that go on to take part in fertilization. Because they are haploid. that means they have one copy of all of the chromosomes and the genes contained within them.
First, the DNA is replicated, and then two cell divisions take place form the haploid gametes. So at first, there are two copies of each gene, creating four after the DNA is replicated.
After the first cell division (meiosis I) there are two cells with 2 copies of every gene. Then to form the haploid gamete, there is another cell division (meiosis II) creating 4 cells each containing one copy of every gene
An ecologist studying plants in the desert performed the following experiment. She staked out two identical plots, which included a few sagebrush plants and numerous small, annual wildflowers. She found the same five wildflower species in roughly equal numbers on both plots. She then enclosed one of the plots with a fence to keep out kangaroo rats, the most common grain-eaters of the area. After two years, to her surprise, four of the wildflower species were no longer present in the fenced plot, but one species had increased dramatically. The control plot had not changed. Using the principles of ecology, propose a hypothesis to explain her results.
Explanation:
- This example highlights the impact of plant predation on species selection. In the fenced off plot animal predation is not a factor on plant selection.
- In this case plants will compete for resources only with each other and in this case one plant had a selective advantage over the other 3 species of plants. In the plot exposed to animal predation the ratio of the four species is equal.
- This is likely do to an increased preference of animals for the plant species that dominates in the fenced off plot and/or anti-animal predation tactics by the other three species.
a.Hypothesis: kangaroo rats are keystone species
-Reintroduce kangaroo rats (and the other locally extinct species)
-Should observe equilibrium re-established
b.Hypothesis: kangaroo rats exert top-down control on community
-Reintroduce kangaroo rats (and other locally extinct species)
-Increase kangaroo rat population in other plot
-Decrease (but don't eliminate) kangaroo rat population in other plot
c.Hypothesis: Locally extinct species inferiorly competed with the extant species of plant
-Remove surviving species from other plot (and remove kangaroo rat population)
Answer:
A suitable place to get tested for an STI is a community health clinic.
Answer:
The fossil record shows that early species of horses were generally small in size, but many lineages since about 30 million years ago exhibit substantial change toward an increase in size.
Explanation:
It was demonstrated that variation in size as well as in diet during the last millions of years, were consequences of different climatic and geographic changes.
The fragmentation of horses´ populations was associated with habitat heterogeneity and to a new tendency for colonizing new areas that were not accessible before that time.
When great plains with grasslands appeared, horses moved to these new areas, reproduced, and got bigger and taller with time. The new species became even bigger. They evolved from small mammals that fed on shrubs in the forests, to the big current horses that graze on the open plains.