Different responses triggered by thyroxine in different organisms is most likely due to different kinds of receptor and consequently different signal cascade and response.
The thyroid hormones (including thyroxine) bind to a specific types of nuclear receptors, termed the thyroid hormone receptors which together with corepressor molecules, bind DNA regions called thyroid hormone response elements.
Answer:
As the area of negative charge at the base of the thundercloud builds up, it induces a region of positive charge to develop on the ground below. As a result of this, a potential difference or voltage is created across the cloud-to-ground gap. Once the voltage reaches a certain strength, the air between the base of the cloud and the ground develops an electrical conductivity. At first a channel, known as a stepped leader, is formed. Although invisible to the naked eye, this allows electrons to move from the cloud to the ground.
It is called a stepped leader because it travels in 50 to 100 m sections, with a slight pause in between, to the ground. As it nears the ground, a positively charged streamer fires upwards from the ground to connect with it. Streamers are most often initiated from tall objects on the ground.
Once connected, electrons from the cloud can flow to the ground and positive charges can flow from the ground to the cloud. It is this flow of charge that is the visible lightning stroke.
After the first discharge, it is possible for another leader to form down the channel. Once again, a visible lightning stoke is seen. This can happen 3–4 times in quick succession. All of this happens in a time interval of about 200 milliseconds.
Answer:
The mRNA for an Alzheimer-related gene is 2400 nucleotides long when isolated from neurons, but 2900 nucleotides long when isolated from glial cells. Genomic DNA isolated from the two cell types show the identical nucleotide sequence. the mechanisms that best accounts for the difference in the sizes of the mRNAs is the alternative slicing mechanism.
Explanation:
A controlled process during gene expression that results in a single gene coding for multiple proteins is referred to as alternative splicing.
During this process, particular exons of a gene may be included within or excluded from the final, processed messenger RNA (mRNA) produced from that gene.
Thus, the mechanisms that best accounts for the difference in the sizes of the mRNAs is the alternative slicing mechanism.
Answer:
increase in watervapor hence an increase in rainfall
