Fossils up to 75,000 years old can be dated with Carbon-14.
Radio isotopes can be used for the age determination of the fossils. Carbon-14 is a common isotope which is used for that purpose. But the half- life of the Carbon-14 is relatively small as 5730 years. That means the amount of Carbon-14 will be half after every 5730 years. Hence, decay is very fast. So Carbon-14 cannot be used forage determination which is more than 75000 years due to the low accuracy.
And: Facilitated diffusion is a type of passive transport that allows substances to cross membranes with the assistance of special transport proteins. Some molecules and ions such as glucose, sodium ions, and chloride ions are unable to pass through the phospholipid bilayer of cell membranes.
Answer:
Natural Selection
Explanation:
In natural selection process of evolution, traits that are essential for an individual to be fit enough to survive under environmental stress become dominant.
Since the flowers are of blue or yellow color, it is essential for a bee to be able enough to perceive the blue and yellow color. Hence, the eyes of bee with time have evolved to perceive these two color so that they can pollinate flower.
The four phases of the menstrual cycle are menstruation, the follicular phase, ovulation, and the luteal phase. Common menstrual problems include heavy or painful periods and premenstrual syndrome (PMS). Knowing when in the menstrual cycle a woman is most likely to conceive can increase the chance of pregnancy.
Answer:
A teacher thinks that students do better on tests when they get to write essays instead of multiple choice. He thinks this because the students can explain their reasoning. On multiple choice questions, students cannot do that and he cannot give students partial credit. The teacher gives one class multiple choice questions and the other essay questions. He compares the scores after each class. Identify the: INDEPENDENT VARIABLE, DEPENDENT VARIABLE, HYPOTHESIS, EXPERIMENTAL GROUP, and CONTROL GROUP.
Essay question is the independent variable while the multiple choice is dependent variable. The hypothesis remains the fact that his thought about students performance in essay questions better than multiple choice questions, experimental group remains both essay and multiple choice questions and the control group is the essay question
Explanation:
