Answer:
The correct answer is option A. "They only introduce supercoiling and cannot relax a covalently closed circular DNA".
Explanation:
Type II topoisomerases are enzymes that regulate the winding an unwinding of DNA during DNA replication. Basically, these enzymes are the scissor that remove the knots and tangles formed during the replication process. Is false to affirm that type II topoisomerases only introduce supercoiling and cannot relax a covalently closed circular DNA. Bacterial type II DNA topoisomerases work with the circular DNA of bacterium by changing the linking number of circular DNA by ±2.
Answer:
Microglial cells
Explanation:
Microglial cells are one of the various types of neuroglial cells in the central nervous system. Microglial cells are the small cells and have thin slender processes. Many spine-shaped outgrowths come out of these processes. Microglial cells serve as phagocytes of the central nervous system. These cells clean the cellular debris that is generated during the normal development of the nervous system. Microglial cells also perform phagocytosis of microbes and damaged nervous tissue.
Answer:
Option (4).
Explanation:
Corpus callosum is also known as callosal commissure. This area is present beneath the cerebral cortex of the brain. Corpus callosum is present in placental mammals only.
The corpus callosum connects the left and right side of body.The severed or improper functioning of corpus callosum may disturb the coordination of action and speech of the right and left side of body.
Thus, the correct answer is option (4).
Answer:
Ecological and ethological approaches to the study of behaviour. The natural history approach of Darwin and his predecessors gradually evolved into the twin sciences of animal ecology, the study of the interactions between an animal and its environment, and ethology, the biological study of animal behaviour.
Answer: The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties.
Explanation:
Starch and Cellulose flare both polysaccharides which are constructed from the same monomer called glucose. The functions they provide in plants are different which includes the following:
- STARCH is used by plants for energy storage because unlike Cellulose, it's formed from glucose units( oriented in the same direction) connected by alpha linkages which can form compact structures that can easily be broken down.
- Cellulose provides structural support for plant cell wall because unlike Starch, it's formed from glucose units( which rotates 180 degrees around the axis of the polymer backbone chain) connected by beta linkages. This pattern gives Cellulose it's rigid features as is allows for hydrogen bonding between two molecules of Cellulose.
Therefore the statement that best describes why starch and cellulose provide different functions in plants is that (The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties).
