Answer:
DNA replication is a semiconservative process.
Explanation:
The DNA molecule is made of two chains (or two strands), also called double-stranded (two chains).
There is complementarity of nucleotides or nitrogen bases:
- Thymine with Adenine,
- Guanine with Cytosine.
This DNA molecule is duplicated. For this, locally, we have an opening of these two chains by enzymes. We speak of enzymatic complex. This set of enzymes comes to open both strands of DNA. After opening the two strands, in the nucleus, there are several free nucleotides which bind to the template strand by complementarity.
We had a single molecule of DNA, we then had two. The two chromatids (or the two DNA helices) are therefore sister, because they are strictly identical. We speak of a semi-conservative replication because we keep one of the two matrix strands to copy identically its complementary, thanks to the complementarity of nucleotides or nitrogenous bases.
Answer:
Study of comparative anatomy emerged in the 18th century and led to establishment of relationship between species based on the common traits
Explanation:
The three major events that occurred after this discovery are –
a) Discovery of the fact that the age of earth is much higher than the age of earth as found in previous theories of continental drift theory
b) The age of the oldest fossils was determined and based on that relative age of all species (as found in fossils) was determined.
c) The determination of age of fossil helped to find the gaps in the evolutionary tree and hence provoked search of these missing species.
The study of comparative anatomy started somewhere around 1800 when George Cuvier emerged as father of comparative anatomy
Based on comparative anatomy study, scientists such as Buffon and Lamarck worked on establishing relationship between species based on the common traits shared between them
Answer:
schistosomiasis
Explanation:
Helminths are the parasites with a worm-like body structure and include the flatworms, tapeworms, and nematodes.
Trematode flatworms are the flatworms that cause the disease schistosomiasis. The schistosomiasis parasite is spread when freshwater snail releases its larva in the water bodies which in turn enter the healthy person bathing in the water.
Answer:
Charles Robert Darwin (1809-1882) transformed the way we understand the natural world with ideas that, in his day, were nothing short of revolutionary. He and his fellow pioneers in the field of biology gave us insight into the fantastic diversity of life on Earth and its origins, including our own as a species.
The answer is B. Geology has shown a thin layer of iridium (a rare mineral on earth but found on asteroids and meteors) in the rock layers between the Cretaceous and Paleogene periods. Below this layer are numerous fossils of pterosaurs and dinosaurs, but above the layer are drastically few. The aftermath of asteroid impact is believed to have smothered most vegetation from earth which dinosaurs depended on as a source of food.
