Answer:
Gated ion-channels
Explanation:
These ion channels are protein molecules that act as a passageway which span across the cell membrane allowing the movement of ions from one side of the membrane to the other. They possess the ability to open and close in response to either chemical or mechanical signals.They possess a fluidic pore, which becomes available to ions after a conformational change in the protein structure has been activated causing the ion channel to open. Based on the stimulus to which they respond, ion channels are divided into three groups: voltage-gated, ligand-gated and mechano-sensitive ion channels. Channels responding to electrical (voltage-dependent ion channels), mechanical, or chemical (ligand-gated ion channels) stimuli open and allow rapid ion movement into or out of the cell, and this movement creates an electrical signals.
<u>Answer:</u> "Chemical fossils"evidence supports the notion that sponges are some of the earliest known multicellular animals.
<u>Explanation:</u>
Sponges are multicellular animals, may belong to Ediacarian period likely to be 80 million years ago or earlier. They catered through a complex system of internal channels, by moving seawater.
Sponges are soft-bodied and very rarely protected as fossils, therefore finding evidence of existence is giant task. The key of their existence came to know from abnormal chemicals which is a steroids of a particular type generated sufficiently by them but virtually never by ordinary organisms.
Analysis of long strata sequence found in Oman and researchers have been able to extract these "chemical fossils" from samples spanning tens of millions of years — before, during and after the Ediacarian period.This gave clear evidence that sponges had to have evolved long before the great variety of multicellular organisms proliferated at the dawn of that time.
Answer: d. All the above
Fertilizers can be deterimental to the environment. Excess use of fertilizers will result in eutrophication in the water body. Water body being more enriched with nutrients will result in excessive growth of aquatic plants. This also result in algal bloom in which algae grows on the surface of water body because of this atmospheric oxygen not able to reach the aquatic plants, hence results in oxygen depletion.
Color blindness is a recessive x-linked trait in humans. In a family where the mother is color-blind, and the father is normal, the probability of their having a color-blind son is 100%.
Color blindness is a recessive x chromosome liked recessive disease which is more prone in males than in females. As the mother is color-blind she has both the alleles of colorblindness while the father is normal with both x chromosome and y chromosome normal.
So if the parents have a boy, he will always receive an x chromosome with colorblindness gene from the mother and a normal y chromosome from the father always. Thus, the probability of having a colorblind boy will be 100%.
To know more about colorblindness refer to the link below
brainly.com/question/2094919
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Answer:
The weather of a region depends on amount of sunlight it receives, its height above sea level, the shape of the land, and how close it is to oceans.
Explanation:
