A. Natural Selection. This is because the weeds that are not resistant to it die out before they can reproduce, but the resistant ones grow to maturity and then reproduce, passing down the resistance gene. Over time, the resistance gene would become a normal thing in weeds, while the non-resistant gene would not exist anyone, since the gene could not be passed on.
Answer:
Red blood cells are a type of specialized cell that move <u>oxygen </u>and carbon dioxide throughout the body.
A structure made of two or more tissues working together to achieve a common function is a/an <u>an</u><u> </u><u>organ</u><u> </u>
<u>cellular </u><u>defferentiation</u><u> </u>describes the degree of specialization that a cell is able to undergo.
A/An <u>embroynic</u><u> </u>stem cell can differentiate into all cell types found within an embryo.
In <u>cytoplasm</u> organisms, all cellular activities take place within a single cell.
Answer:
A woman creates new immature ova in the ovary each time she has a menstrual cycle.
Explanation:
During the menstrual cycle, hormones present in the body make the immature eggs 'mature' ones, in the ovary. About in half of the cycle, hormones make the release of the mature egg from the ovary and travels towards uterus. It can remain there for 24 hours and if not fertilized the it breaks down and released out.
Natural selection is the process that result in the adaptation of an organism to environment by means of selectively reproducing changes in its genotype, or genetic constitution. It is the a key mechanism of evolution. Charles Darwin popularised the term "natural selection" contrasting it with artificial selection, which is intentional, whereas natural selection is not.
To make it simple, let's have a group of beetle composing of green and some are brown as an example. here, there is a variation in traits. Since the environment could not support continuous population growth, not all species can reproduce to their full potential. Green beetles can easily be eaten by other species like birds compared to brown beetles. The surviving brown beetles will then generate brown offsprings because their trait has a genetic basis. Since more brown beetles survive and becomes more common in the population, the process continues until all individuals will eventually be brown. so basically, if you have variation, differential reproduction, and heredity, you will have evolution by natural selection as an outcome.
Answer:
Explanation:
The fossil record
This supports Darwin's theory of evolution, which states that simple life forms gradually evolved into more complex ones. Evidence for early forms of life comes from fossils. By studying fossils, scientists can learn how much (or how little) organisms have changed as life developed on Earth.