Answer: I would go with B. Here’s why: An index fossil is usually easily recognizable, and underwent a wide geographic distribution. What leads me to believe B is the correct answer, is because it’s something that existed “ all over the world”.
Explanation:
Las células eucariotas son muy diversas en forma, forma y función. Sin embargo, algunas características internas y externas son comunes a todos. Estos incluyen una membrana plasmática (celular), un núcleo, mitocondrias, orgánulos unidos a la membrana interna y un citoesqueleto.
The fact that each plant gets only one allele
from each parent plant is detailed in the law of segregation
Answer:
The barrier functions to regulate the chemical composition of the extracellular fluid surrounding the brain cells.
Explanation:
Blood-brain barrier
It is a very selective semipermeable membrane , hence allow some specific substance to pass via it . This barrier separates the extracellular fluid in the central nervous system and the circulating blood from the brain .
<u>The barrier is composed of the endothelial cells .</u>
Passive diffusion is shown in this system , and allows molecules like the water , glucose , amino acid to pass .
It regulates the chemical composition of the fluid of brain cell .
What are you asking? i cant help if i cant understand
