True. Because its staying still
Answer:
DNA replication a process of copying of a cell's DNA. DNA replication is semiconservative process which means that each strand in the double helix helps in the synthesis of new, complementary strand and conserve the parent template.
The Molecular mechanism of DNA replication is as following:
- The double starnded DN in binded with hydrogen bond, the enzyme helicase opens up the DNA at the replication fork.
- A single stranded binding protein prevent the rewinding of DNA and so binds to the DNA around the replication fork
- Topoisomerase prevent supercoiling at replication fork.
- The ezymes primase come in action and produces RNA primers which are complementary to the DNA strand.
- DNA polymerase III help to extends the primers and allow them to add to the 3' end, to make new DNA.
- DNA Polymerase then remove RNA primers and replace with DNA.
- DNA ligase blocks the the gaps between DNA fragments.
So, this is the molecuar mechanism of DNA replication.
Answer:
The placenta is the temporary association of fetus and maternal tissue. It is meant for nutrition and transport of different substances.
Explanation:
The placenta is a temporary association of fetal and maternal tissues. The placenta is formed from the trophoblast of the blastula. These trophoblasts form chorionic villi which later forms the placenta. The chorion and allantois also take part in the formation of the placenta. Hence, the human placenta is known as the chorioallantoic placenta. The process of formation of the placenta is known as placentation.
The placenta has several functions but the major function is to provide nutrition to the fetus. The developing fetus gets nutrition from the mother's body by the placenta. The placenta provided with blood vessels which help in the transportation of different substances. It also helps in gas exchange between the mother and baby. Thus it plays a vital role in fetal respiration. The metabolic wastes diffuse through the placenta. Placenta also stores fat, glycogen, which participates in protein metabolism.
Answer:
Answer is A. allow them to control all the variables involved.
Explanation:
Modelling in ecology means the use of constructed mathematical models for understanding of ecological processes and to predict or know how real it is for ecosystem to change.
Ecological modelling is useful in defining problems more precisely and clarity of concepts.
