Answer:
Chromatin is a substance within a chromosome consisting of DNA and protein. The DNA carries the cell's genetic instructions. The major proteins in chromatin are histones, which help package the DNA in a compact form that fits in the cell nucleus. Changes in chromatin structure are associated with DNA replication and gene expression.
Explanation:
Appalachian: A. Two continents colliding.
The Appalachian mountain range is an ancient example of a collision between two continental plates. Both plates have low density and little subduction occurs between them.
North American Cordillera: B. Terrane accretion
These form when two continents that collided bonded so tight that it forms a permanent land mass. If the continents would pull away from each other, the terrane stays intact.
Aleutian plate: D. Oceanic convergence
This is a type of convergence where one plate subducts beneath another plate. Between the two, the older plate is usually the one that subducts because it is usually more dense.
Andes mountain range: C. An oceanic plate and continental plate colliding.
In the collision between an oceanic and continental plate, the thinner and more dense oceanic plate subducts under the continental plate. The Andes mountain range was formed by the subduction of the Nazca Plate beneath the South american Plate.
Natural selection allows nature to chose which species survives. Only the fittest get to pass on their genes. And by fittest i mean the ones that are better adapted to the environment.<span />
Answer:
A fall-arrest system should be worn while climbing a tree or any tall structure. This will enable the person to have a thing to break or slow his fall if he loses his grasp from the trunk of the tree.