In eukaryotes, the DNA strands are linear, and DNA polymerase can't replicate the very ends of the DNA strands! These ends are "protected" by repeated sequences called "telomeres." Either the chromosome gets shorter with each replication, or else a special enzyme-nucleic acid complex called telomerase adds new telomeres to the ends. A prokaryotic chromosome is circular and thus does not have the problem of having ended.
<span>Eukaryotic DNA is wound around histones, coiled, and supercoiled -- to replicate it, there have to be unwinding mechanisms, and mechanisms to reduce the degree of coiling. In prokaryotes, the winding problem is much less, and there aren't any histones.</span>
Answer:
The Biosphere
Explanation:
The biosphere is made up of all living organisms and is inextricably linked to the other three spheres: most live organisms need gases from the atmosphere, water from the hydrosphere, and nutrients and minerals from the geosphere.
Answer:
i) Glucose
ii) β(1-4) glycosidic bonds.
iii) Oxygen
Explanation:
Cellulose is an important structural carbohydrate found in plants. It forms a major component of the plant cell wall.
Cellulose is a polysaccharide formed by monomers of glucose. These glucose monomers are joined together by covalent bonds called β(1-4) glycosidic bonds, which means that the 1st carbon of one glucose is bound to the 4th carbon of the next glucose. To make this arrangement, every other glucose molecule in cellulose is inverted, which you can see in the diagram.
Glucose monomers contain carbon, hydrogen, and oxygen only. If you look at the pattern of the molecule (remembering every second glucose is inverted), you can see that Z must be O.
The functional group denoted by Z is oxygen. The OH groups on the glucose from one cellulose chain form hydrogen bonds with oxygen atoms on the same or on another chain, holding the chains firmly together and forming very strong molecules - giving cellulose its strength.
Answer:
Corn Picker. In 1850
Cotton Gin.
Cotton Harvester.
Crop Rotation.
The Grain Elevator.
Hay Cultivation.
Milking Machine.
Plow.
Explanation:
there are some agriculture inventions
