Answer:
<h2>c. Division of these two groups occurred after the protostome developmental sequence appeared. </h2>
Explanation:
- Protosomes are such types of organisms in which the mouth part developed first during embryonic development.
- Those animals in which anus develop first are known as deuterostomes.
- This differentiation takes place during the embryonic development of the organisms.
- Since lophotrochozoan and Ecdysozoa both are protostomes animals and categorized on the basis of molecular evidence.
- Thus these two groups were formed after the appearance of the protostomes.
Answer:
fertilization is the process of fusion of gametes from two parents. gametes are produced as a result of meiosis in which crossing over and recombination produces new combinations of genes and sometimes mutations are also occur which also leads to development of unique characteristics.
this is the main reason that kids from same parents are genetically unique.
Explanation:
Adenine pairs with thymine (or uracil), and guanine pairs with cytosine.
my answer would be the 3rd one
my bad if i'm wrong
The correct answer is: A checkpoint will be activated if the spindle does not attach to a kinetochore.
Prokaryotes, do not undergo mitosis (like eukaryotes) and therefore have no need for a mitotic spindle. Prokaryotes also don’ t have checkpoints foor the regulation of cell division.
Normal eukaryotic cells (unlike cancer cells), move through the cell cycle in a regulated way in order to make sure that cells don't divide under conditions that are unfavorable for them. Information about their own internal state (nutrients, signal molecules, DNA integrity) is signal to go or not to go through the cell division. Because of that there are few checkpoints in the cell cycle at which the cell examines the signals and makes a “decision”. The major checkpoints are:
• The G1- the first point at which it must choose, once it passes the G1 checkpoint the cell enters S phase
• The G2-the cell checks DNA integrity and checks if replication is done well.
• The spindle checkpoint-at the transition from metaphase to anaphase.
