C. They are not enclosed by a membrane.
D is incorrect because Ribosomes do not contain DNA, the nucleolus does.
B is also incorrect because they aren't located outside the cell, they're in the cell, on the endoplasmic reticulum.
Hoped this helped :)
Answer:Four spheres of earth are:1)Lithosphere(land) 2)Hydrosphere(water) 3)Biosphere(living things) 4)Atmosphere(air).
Energy and matter flow through Earth's four spheres.Energy flows through the atmosphere and hydrosphere mostly by convection.The continuous cycling of matter and energy through earth's system makes life on earth possible .Others are driven by energy from the sun.
Explanation:
Answer:
People who acquire advantageous features have a greater chance of surviving, whereas individuals who have less useful traits are weeded out by natural selection. The higher the diversity of characteristics in a population, the greater the population's chances of survival.
When Denise mixed the blood with water, it formed Osmosis. There is water in the blood as well as a concentration of salt.
Coin flipping simulates the events of mitosis and the production of sperm. This is because females carry XX chromosomes so all eggs will have a singular X chromosome. It is the sperm that determines the sex of the foetus: males have XY chromosomes and therefore sperm will carry either X or Y chromosomes (a 50/50 chance, just like flipping a coin)