Ryan is looking at a cell under a microscope, he observes formation. he observes spindle microtubules from the centrosomes. which phase of the cell cycle is he observing?

a: metaphase.

b: anaphase

c: prophase

The right option is C: prophase

Prophase is the phase of the cell cycle Ryan is observing.

Prophase is the first stage of mitosis during which the chromatin condenses to form the visible chromosomes. Also, a structure known as mitotic spindle which is composed of long proteins (microtubules) begin to form from the opposite ends of the cell (centrosomes) and a part of the nucleus where ribosomes are produced disappears during this phase.

4.) metal

"-the movement of carbon from the nonliving environment into living things and back to the environment

-carbon is the essential component of proteins, fats, and carbohydrates (which make up all organisms)

-carbon exists in air, water, and living organisms

-producers convert carbon dioxide in the atmosphere into carbohydrates during photosynthesis

-bacteria in the atmosphere cycles through the system in filtration units

-in cellular respiration, carbon is released back into the atmosphere as carbon dioxide

-some carbon is stored in limestone (forming one of the largest "carbon sinks" on earth)

-largest carbon reservoir on earth= limestone

-carbon stored in the bodies of organisms as fat, oils, or other molecules may be released into the soil or air when the organism dies

-this may form deposits of coal, oil, or natural gas (fossil fuels, which increased the atmospheric carbon dioxide)

-fossil fuels store carbon left over from bodies of organisms that died millions of years ago

-they are located in the surface of earth, deep within the earth and beneath the ocean floor."