Answer:
A higher rate of concordance in monozygotic twins in comparison to dizygotic twins is a proved evidence of the contribution of the genetic constituent as monozygotic twins are genetically more identical in comparison to dizygotic twins. The monozygotic twins share all the genes in common and dizygotic twins on average share half of their genes in common.
Thus, the concordance in monozygotic twins is more in comparison with that of dizygotic twins, which shows the contribution of genetics to this trait.
Answer:
Explanation: The sugar and phosphate group make up the backbone of the DNA double helix, while the bases are located in the middle. A chemical bond between the phosphate group of one nucleotide and the sugar of a neighboring nucleotide holds the backbone together.
MITOSIS results in the formation of a new cells with a full set of chrimosomes
Answer:
The circulatory system, also called the cardiovascular system or the vascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilize temperature and pH, and maintain homeostasis.
There are two main types of circulatory systems: 1. open circulatory systems and closed circulatory systems. Open circulatory systems are systems where internal organs and body tissues are surrounded by circulatory fluid. This fluid is called hemolymph, and it's pretty much like blood, except that it doesn't contain oxygen transporting cells.
2. The closed circulatory system of some mollusks and all vertebrates and higher invertebrates is a much more efficient system. Here blood is pumped through a closed system of arteries, veins, and capillaries. Capillaries surround the organs, making sure that all cells have an equal opportunity for nourishment and removal of their waste products. However, even closed circulatory systems differ as we move further up the evolutionary tree.
The central nervous system is made up of the brain and spinal cord<span>.</span>
