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Elena-2011 [213]
3 years ago
15

A radioactive element has a half-life of 1000 years. A rock contains 6.25% radioactive material. How old is the rock?

Biology
1 answer:
Natali5045456 [20]3 years ago
7 0

ANSWER:

Radioactive element life years = 1000/2 = 500yrs.

So, Rock years

  • 6.25/100 × 500
  • 31.25years.
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Which organism would the researchers most likely predict to be the most distantly related to eukaryotes?.
Marizza181 [45]

Answer:

Organism I (circular chromosomes)

Explanation:

I can eliminate organisms II, III, and IV because these organisms have linear chromosomes therefore making it the most closely related to eukaryotes because they consist of linear chromosomes. My only other choice would be organism I, and since it has circular chromosomes we can conclude that this is the most distantly related to eukaryotes.

7 0
2 years ago
Read each description below regarding innervation of the ANS. Then click and drag each into the appropriate category base on whe
Anna35 [415]

The question is incomplete. Here is the complete question.

Read each description below regarding the dual innervation of the ANS. Then click and drag each into the appropriate category base on whether it is an example of antagonic or cooperative innervation.

The sympathetic division stimulates mucus production by salivary glands while the parasympathetic division stimulates enzyme secretion.

The sympathetic division stimulates am increase in heart rate while the parasympathetic division stimulates a decrease in heart rate.

During sex, the parasympathetic division stimulates arousal while the sympathetic division stimulates orgasm.

The parasympathetic division constricts the pupils while the sympathetic division dilates the pupils.

Antagonistic:

Cooperative:

Answer: <u>Antagonistic:</u> The sympathetic division stimulates am increase in heart rate while the parasympathetic division stimulates a decrease in heart rate; The parasympathetic division constricts the pupils while the sympathetic division dilates the pupils.

<u>Cooperative:</u> The sympathetic division stimulates mucus production by salivary glands while the parasympathetic division stimulates enzyme secretion.; During sex, the parasympathetic division stimulates arousal while the sympathetic division stimulates orgasm.

Explanation: The peripheral nervous system is divided in <u>Somatic Nervous System (SNS)</u> and <u>Autonomic Nervous System (ANS)</u>. The first is responsible for sensory input and voluntary motion.

Autonomic Nervous System is divided into <u>Sympathetic and Parasympathetic divisions</u> and is controls the fight-or-flight and rest-and-digest situations. Usually, an organ with sympathetic and parasympathetic innervations have antagonic function, such as the heart rate -  one system causes the heart rate to increase while the other stimulates the rate to decrease. However there are cases in which the combination of the 2 systems cause an increase of stimulation, producing similar effects.

Analysing each category above, it is deductable that when the sympathetic stimulates mucus production and parasympathetic, enzyme secretion and when the parasympathetic stimulates arousal and sympathetic, orgasm, in both cases, they have cooperative innervation.

On the other hand, when sympathetic stimulates increase in heart rate and parasympathetic, decrease in the rate, as stated before, and one stimulates constriction of the pupils and the other, dilation of the them, those are examples of having antagonic innervation.

5 0
3 years ago
2 Points
SVEN [57.7K]

Answer:

B, A fossil found in rocks from one time period

Explanation:

Fossils are used to determine the ages of rock layers. Index fossils are the most useful for this. Index fossils are of organisms that lived over a wide area. They lived for a fairly short period of time. An index fossil allows a scientist to determine the age of the rock it is in. Hope that this helps you :)

3 0
3 years ago
Why are some planets harder to see than others planets in the solar system
arsen [322]

Answer:

Because they are farther away

Explanation:

3 0
2 years ago
What causes evolution?
Zina [86]

bring change in the genetic basis of a population

5 0
3 years ago
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