Which organelle can be compared to a security guard who decides whom may enter a building and whom may not? a: cell membrane b: cytoplasm c: endoplasmic reticulum d: mitochondrion

Based on the evidence in the excerpt above, describe in your own words what it would have been like for a person to enter a meat processing plant in the united states

What type of specimens where you able to see under each of the microscopes in the microscope activity

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2