1 point

Ocean water is about 96.5% water. How many elements make up most of Earth’s ocean water? (Hint: Step 1. Recall and draw the stru

arlik [135]

Answer:

d

Explanation:

6 0

3 years ago

The bones from an animal found at an archaeological dig have a C614 activity of 0.10 Bq per gram of carbon. The half-life of C61

erastova [34]

C14 is an isotope used in radiocarbon dating techniques to date organic matter remains. The age of these bones is approximately 6890 years.

<h3>What is Carbon 14?</h3>

Carbon 14, also known as radiocarbon, is a radioactive carbon isotope.

Isotopes are the atoms of the same element -carbon- that vary in neutrons and, hence, in their massic number. They are alternative forms of the same element.

The radioactive C14 nucleus contains 6 protons and 8 neutrons and has a half-life of 5730 years.

The term half-life is a reference. It means that an organism that has been dead for 5730 years has half the C14 amount or concentration than the same organism had when it was alive.

Knowing the half-life of an element is useful to determine the age of the dead matter.

C14 is used in radiocarbon dating techniques or methods to estimate the age of fossils. This is a reliable technique used for dating organic samples that are less than 50,000 years old.

Available data:

The half-life of C14 is 5730 years
Bones activity of 0.10 Bq per gram of carbon

To answer this question we can make use of the following equation

Ln (C14T₁/C14 T₀) = - λ T₁

Where,

C14 T₀ ⇒ Amount of carbon in a living body. We know, by bibliography, that living organism activity is 0.23 Bq per gram of carbon. So, C14 T₀ = 0.23 Bq/g

C14T₁ ⇒ Amount of carbon in the dead body. C14T₁ = 0.1 Bq/g

λ ⇒ radioactive decay constant = (Ln2)/T₀,₅

T₀,₅ ⇒ The half-life of carbon 14 = 5730 years

T₀ = Time when the organism was alive

T₁ = Age of bones

Let us first calculate the radioactive decay constant.

λ = (Ln2)/T₀,₅

λ = 0.693/5730

λ = 0.0001209

Now, let us calculate the first term in the equation

Ln (C14T₁/C14 T₀) = Ln (0.1/0.23) = Ln 0.4347 = - 0.833

Finally, let us replace the terms, clear the equation, and calculate the value of T₁.

Ln (C14T₁/C14 T₀) = - λ T₁

- 0.833 = - 0.0001209 x T₁

T₁ = - 0.833 / - 0.0001209

T₁ = 6889.99 ≅ 6890 years

The bones are approximately 6890 years.

You can learn more about dating organic matter with carbon14 at

brainly.com/question/4149380

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6 0

2 years ago

Pls answer its due soon!!!

pickupchik [31]

Explanation:

Meiosis makes genetic variety possible. It makes sperm & egg cells called gametes. Each gamete has 23 chromosomes. To make a diploid cell two gametes (sperm & cell) come together.

During prophase 1 the chromosomes pair up with their homologous pairs so they can transfer their genetic information and exchange it between each other. It makes recombinant chromosomes that influence the genetic diversity between the same people.

Now they are in metaphase 1, the chromosomes are in pairs in the middle of the cell. In anaphase 1, the chromosomes are pulled away by the spindle fibers. Then in telophase 1, there are two formed nuclei. Cytokinesis 1 then splits the cytoplasm.

Now they are in meiosis 2. During prophase 2, there are chromosomes and the spindles are starting to form again without crossing over like in prophase 1. In metaphase 2, chromosomes are going to line up in the middle in both cells unlike during metaphase 1 where the chromosomes were only in pairs. In anaphase 2, only the chromatids are being pulled away by the spindle fibers. Next in telophase 2 the nuclei reform and the 2 cells are each going to divide into 4 cells. Finally, cytokinesis completely splits the cytoplasm.

Keeping in mind that each sex only produces one type of gamete cell (sperm or eggs), and of the independent assortment and crossing over of chromosomes, the end result will be diversity.

5 0

3 years ago

In a species of fish, fin shape is controlled by a single gene that has only two alleles. In a generation of 185 fish, the frequ

scZoUnD [109]

The correct answer is: The recessive allele produces a phenotype that is better able to survive and reproduce than the dominant phenotype.

Natural selection (adaptation mechanism), gene flow, and mutation combine to change allele frequencies across generations. Natural selection tends to increase in frequency beneficial alleles, while it tends to decrease in frequency deleterious alleles.

5 0

3 years ago

What element does your model represent?

AfilCa [17]

Answer:

I guess photosythesis

Explanation:

6 0

3 years ago