<h2>R
eceptor</h2><h2>
Explanation:</h2>
The cell to cell communication is performed by certain chemical signals in the multi-cellular organisms. The chemical signal is perceived by the cell with the help of receptor. The signalling molecule binds to receptor thereby generating a response. The signalling molecule can only bind to a specific receptor. For example, nerve growth factor can only bind with nerve growth receptors and insulin binds only with insulin receptor.
Thus, To receive and respond to a chemical signal, a cell must have a <u>receptor</u> for that chemical.
Learn more: receptor
1. https://brainly.in/question/3558369
Cell to cell signalling
2. https://brainly.in/question/11252650
<h2>Answer 1 with Explanation</h2>
The DNA model represents the genetic code that defines all the characteristics of a living thing and it is made up molecules called nucleotides. Each nucleotide contains and represents a phosphate group, a nitrogen base, and a sugar group. Two long strands are formed by Nucleotides attached together to create a structure called double helix which looks like a ladder, the sides would be made up of sugar and phosphate molecules while the rungs would be the base. The straws represent the sugar-phosphate backbone which forms the structural framework of nucleic acids. It is composed of alternating sugar and phosphate groups.
<h2>Answer 2 with Explanation</h2>
The push pins re-presence nitrogen-containing base is an essential molecule with a nitrogen atom having the chemical features of a field. The principal biological purpose of a nitrogenous base is to bond nucleic acids collectively. A pushpin owes its essential characteristics to a solitary couple of electrons of a nitrogen atom. It is assigned as the derivatives pair of parent compounds.
<h2>Answer 3 with Explanation</h2>
The paper clips represent ‘five prime’ and ‘three prime’ which indicate the number of carbons in the DNA’s sugar backbone. These two are the distinctive ends of the nucleic acids. The black dots represent the bonds of sugar and phosphate which make up the nucleotides and show the genetic code. These bonds have strong covalent bonds that keep the bonds attached together firmly.
<u>Answer</u>:
<u>Question 1.</u> 1.fragmentation The roads act as barriers which cannot/or will not be crossed by many forest dwelling species. They are either physical or psychological barriers for animals. The presence of humans and cars further increases this effect. Thus, the original forest habitat becomes fragmented into smaller areas with smaller populations.
<u>Question 1.</u> 2.find an unrelated mate
As the forest becomes fragmented, the original area and population of a species is divided into smaller units. Thus, for the individuals belonging to such a diminished population, the chances of finding an unrelated mate will decrease rapidly with time. This will lead to inbreeding and a loss of genetic diversity.
