the answer is d nucleus acids.
extinction would lead to the extinction of other forms of life. A keystone species helps to
support the ecosystem of which it is a part.
An example of what can happen when a keystone species is removed occurred when fur
hunters eliminated sea otters from some Pacific Ocean kelp beds. Otters eat sea urchins,
which eat kelp. With its major predator gone, sea urchin populations exploded and
consumed most of the kelp. Fish, snails, and other animals associated with the kelp beds
disappeared.
The grizzly bear is another example of a keystone species. Grizzlies transfer nutrients
from the ocean ecosystem to the forest ecosystem. The first stage of this transfer is
performed by salmon that swim up rivers, sometimes for hundreds of miles. Salmon are rich
in nitrogen, sulfur, carbon, and phosphorus. The bears capture the salmon and carry them
onto dry land, scattering nutrient-rich feces (wastes) and partially eaten salmon carcasses.
It has been estimated that the bears leave up to half of the salmon they harvest on the
forest floor.
Which sequence best represents the feeding relationships in a kelp ecosystem that has not been disturbed
by humans?
(1) sea urchins → kelp → fish (3) kelp → sea otters → sea urchins
(2) kelp → sea urchins → sea otters (4) sea urchins → snails → kelp
The correct sequence displaying the feeding relationships in an undisturbed kelp ecosystem is: kelp → sea urchins → sea otters. Kelp serves as a food source for sea urchins, which in turn are consumed by sea otters.
The sequence that best represents the feeding relationships in a kelp ecosystem that has not been disturbed by humans is (2) kelp → sea urchins → sea otters. In an undisturbed ecosystem, the kelp, being a producer, forms the base of the food chain. Secondly, the sea urchins, as primary consumers, feed directly on the kelp. And finally, the sea otters are secondary consumers that prey on the sea urchins, maintaining the balance in the ecosystem.
#SPJ6
Answer and Explanation:
All cells including the gametes contain chromosomes. Each gamete cell after cell division contains 23 chromosomes. After fertilization, the diploid number of chromosomes which is 46 is restored in the zygote.
Meiosis, a type of cell division, has two phases which eventually lead to the formation of four daughter cells with equal number of chromosomes. Gametes are haploid in nature and thus meiosis I involves separation of homologous chromosomes hence the reduction in the chromosome number. Meiosis II involves separation of sister chromatids in the daughter cells resulting in four daughter cells with 23 chromosomes.
Meiosis ensures that chromosoe number does not double with each successive generation as the resulting daughter cells are gametes, two of which must fuse to form a zygote.
In the lytic cycle, the virus hides in the host’s DNA.
Stress can cause a virus to switch from the lytic cycle to the lysogenic cycle.
Stress can cause a virus to switch from the lysogenic cycle to the lytic cycle.
Answer:Option d
Explanation:
The virus cannot live in the environment without the host cell. They need the host cell for their survival.The virus incorporates its genetic material in the genetic material of the host cell to live. They opt for lytic cycle or lysogenic cycle.
Due to environmental stressors such as the starvation or exposure to chemicals may cause the virus to switch from the lysogenic cycle to lytic cycle.
Answer:
Plant and animal life is limited in areas with little access to sunlight.
Explanation:
This is B on edge if you are taking APES :)
Answer:Normally because the flu virus doesn't last very long because your body is very used to the flu.