<span>Charles Darwin theory is theory of biological </span>evolution, that explains how modern organisms evolved over long periods of time through descent from common ancestors. Evolution is the process of change over time and Darwin explains in his theory the changes in humans over time and <span>shows how the living world is constantly changing.</span> This is the reason why cientists refer to charles darwin’s ideas about evolution as the theory of evolution.
Answer:
Fraternal twins are “dizygotic,” meaning that they developed from two different eggs fertilized by two different sperm cells, while identical twins are “monozygotic” i.e., they developed from a single fertilized egg that split.
Explanation:
The following structural changes occur as conducting tubes
become smaller;
- support structures change. The trachea has more hyaline cartilage
than the bronchioles
- epithelium type changes with bronchioles having ciliated
columnar cells with the trachea having tall columnar pseudostratified
- amount of smooth muscle increases as you go lower the respiratory tract
Answer:
a. different alleles of the seed shape gene.
Explanation:
Mendel crossed different varieties of pea plants and he observed how phenotypic traits passed to the progeny. From these experiments, Mendel formulated the 'First Law of Segregation', where he observed that traits may exist in pairs that segregate (separate) at meiosis. During meiosis, i.e., gamete formation, these two factors separate from each other, thereby each gamete has the same probability of receiving either factor. Nowadays, we know that these two factors represent two different gene variants or 'alleles' for a given gene <em>locus</em>. Alleles can be classified into dominant or recessive as in the example above described, where the R factor (round) dominates on the r factor (wrinkled) to determine the seed shape.
Answer:
1. The gametophyte generation is haploid.
2. The embryo is diploid.
3. The megaspore is haploid.
4. The sporophyte generation is diploid.
Explanation:
1. Gametophyte- The gametophytic generation is the structure which produces gametes in the plant. Since the gametes are haploid, therefore, the gametophyte us considered the haploid.
2. Embryo- The embryo is formed after the fusion of fertilization when zygote develops, therefore, is considered diploid.
3. Megaspore- the big size spore which is formed from by the meiotic division of the megasporocyte, therefore, is considered haploid.
4. Sporophyte- the sporophyte generation develops from the embryo which is diploid therefore is considered diploid.
