Answer:
four phenotypes appear in the ratio 9:3:3:1
Explanation:
<em>For a dihybrid cross in which the two genes concerned obey simple dominant/recessive law and are independently assorting, </em><em>four phenotypes are produced in the ratio 9:3:3:1. </em>
The dominant gene takes up the largest ratio (9/16) while the recessive gene takes up the smallest (1/16). Any deviation from 9:3:3:1 and the number of phenotypes produced from a dihybrid cross is an indication that the genes involved do not obey Mendelian laws.
20 chromosomes because unfertilised eggs contains half the number of bodily chromosomes
Answer:
lipid, fatty acid, cell membrane
protein, amino acid, enzyme
carbohydrate, sugar, starch
nucleus acid, nucleotide, DNA
The best description about the brain stem is: it is the most important organ of our body's survival. It connects the brain and the spinal cord, controls the vital organs like the lungs and heart and it also coordinates the many essential body reflexes.
The answer is <span>Topoisomerase.
Topoisomerase is an enzyme responsible for twisting of DNA helix. After DNA strand is untwisted by helicase enzyme, DNA must be twisted again so the normal function of DNA can be sustained. If left untwisted, the replication fork will continue to grow, the normal function of DNA will stop.</span>
