Cellular organelles are the internal organs of a cell. They are responsible for keeping the cell alive. They do this by bringing in food for the cell, getting rid of waste, protecting and repairing the cell, and helping it grow/reproduce.
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.
The fore limbs has the (humerus, ulna, radius, carpals, metacarpals), and digits. While the hind limbs characteristics are the (femur, patella, fibula, tibia, tarsals, metatarsals), and digits.
Answer:
D. Population genetics
Population genetics is the study of genetic variation within populations, and involves the examination and modelling of changes in the frequencies of genes and alleles in populations over space and time. ... In natural populations, however, the genetic composition of a population's gene pool may change over time.
Explanation:
microevolution - evolutionary change within a species or small group of organisms, especially over a short period. (Not studying the overall evolution in the population, just a single allele usually) Not it then
macroevolution - Macroevolution in the modern sense is evolution that is guided by selection among interspecific variation, as opposed to selection among intraspecific variation in microevolution (this goes over huge groups of different species) Not it then
gene pool - The gene pool is the set of all genes, or genetic information, in any population, usually of a particular species. (Not the study of evolution in a population) Not that then
So it has to be D