Desertification is the inability of ecosystems to fulfill their regulatory function caused by deforestation, overgrazing, and overworking the soil.
<h2>What is desertification?</h2>
Desertification is a phenomenon that implies the loss of fertile soils due to climatic variations and human activities.
- The three main causes of desertification are overgrazing, deforestation, and unsustainable agricultural practices.
- Overgrazing and deforestation destroy the protective vegetation layer that covers arid and semi-arid regions.
Therefore, we can conclude that desertification is the process of ecological degradation through which areas of land that were fertile and productive are transformed into deserts.
Learn more about desertification here: brainly.com/question/2426422
Answer: The correct option is B (self-replicating molecules, such as RNA and DNA)
Explanation:
The current theory of the process of evolution makes use of present day knowledge of genes and chromosomes to explain the source of genetic variation upon which natural selection works. These genes are discrete units of inheritance which determine hereditary characteristics. All the information for the inheritable characteristics of an individual are contained in these genes.
When a cell divides, the genes duplicate themselves so that each daughter cell has an identical set of genes as the original parent cell. These genes are passed from parents to offspring in the gametes of the parents.
Gene are found in the DNA( Deoxyribonucleic acid) molecules or RNA (Ribonucleic acid) molecules. These molecules are capable of self replication due to a process called mutation. Mutations are random changes in DNA that alter genetic information and sin introduce new characteristics. They may occur
--> in body cells or
--> during gamete formation.
Thus, evolution from vesicles to true cells is through self replicating molecules through the process of mutation which is the raw material for evolution
Answer:
At the microscopic level of a visceral muscle cell are actin and myosin filaments. They slide past each other in an antiparallel manner to shorten the distances between their ends. In a smooth muscle cell, the ends of chains of these functional units are attached to the cell membrane. They are several in a cell arranged in an elaborate framework. They contract together and deferentially to enable the muscle to contract as needed.
Answer:
C. The pancreas triggers the development of secondary sex characteristics
Explanation:
Edge 2021
