Answer:
Explanation:
The method of reproduction in humans is sexual reproduction: a type of reproduction that occurs when new organisms are produced through the coming together of genetic information from two individuals of different sexes mostly a male and a female (egg cell and the sperm). The genetic information for making the blood cells; the red blood cells genes in particular exists on chromosomes in the nucleus of the sex cells (egg and sperm cell) also called the gametes. Basically, the DNA provides instructions for the production of mostly all of the body's needs.
The genes coding for the sickle cells which is the abnormal red cell is always inherited in the recessive form meaning both parent has to possess one copy each of the defective gene in their DNA. For humans to get one copy of a sickle cell gene and one copy normal gene; it means one of the parents gametes (be it male or female) contributed the defective chromosome and the other normal gene is contributed by the other parent during copulation giving rise to an individual that is heterozygous for the trait
For example, the sperm cell with the defective gene fertilizes the egg cell that has the normal copy of the gene producing an heterozgous individual.
Double fertilization-plants with seeds (flowering plants), two male gametes joining with female gametophyte
Gametophyte generation-both (haploid, sexual stage stage-gametophyte, and the diploid stage that produces spores – sporophyte)
Endosperm formed-plants with seed because it is a tissue formed inside the seed which surrounds the embryo and provides nutrition
Mitosis-both (mitosis occurres in spores)
Spores develop into gametophytes-both but, in seedless plants sporophyte produces spores that will develop into a new organism (multicellular gametophyte) using mitosis, while spores of seed plants are produced internally and develop into more complex structures.
