If darwin was to be alive today,what do you think will be his observation on evolution?

The half life of an element is 14 years how many years old The rock will be after two half-lives

alexandr402 [8]

The rock will be 28 after two half lives

3 0

3 years ago

PLEASE HELP ME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

prohojiy [21]

Answer:

Early experiments on children don't fit today's standards of ethical treatment.

Explanation:

Today, because of advances in ethical considerations scientists would not conduct this experiment never the less get approved to do it because an infant would not be able to speak up and make decisions.

3 0

3 years ago

Who is good at biology and that can help me??????

Aleks [24]

It is kind of difficult for me even, but I know that neutral objects have an even amount of opposite charges. When brought near a charged object the neutral's protons will lean toward excess electrons on the charged one. A positively charged object will attract the neutrals electrons to move toward it. I hope that kind of helped. Sorry if I couldn't give a direct answer! Its kind of hard for me too and I'm an A+ student in bio

5 0

3 years ago

Trace metals, like iron and magnesium, are considered ___________________, while organic compounds, like vitamins, are considere

nordsb [41]

Trace metals, like iron and magnesium, are considered _Building blocks of molecule__________________, while organic compounds, like vitamins, are considered________Complex Molecule___________

5 0

3 years ago

When pink sweet peas were self-pollinated and the seeds were collected and sown, the following flower colors were obtained: Red

Pavlova-9 [17]

Answer:

c. 1:2:1

The results are consistent with incomplete dominance for this trait, with pink flowers being heterozygous.

Explanation:

If flower color were determined by a gene showing incomplete dominance, the possible genotypes and phenotypes are as follows:

RR- red
ww - white
Rw - pink

If pink sweet peas are self-pollinated, then a cross between two heterozygous individuals is done (Rw x Rw).

From this cross the expected ratios are:

1/4 RR (red)
2/4 Rw (pink)
1/4 ww (white)

So the null hypothesis is that the observed results exhibit a 1:2:1 ratio.

<h3>Chi square test</h3>

$X^{2} = \sum \frac{(Observed - Expected)^2}{Expected}$

The observed frequencies were:

34 Red
76 Pink
40 White

Total 150

The expected frequencies for our null hypothesis are:

1/4 x 150 = 37.5 Red
2/4 x 150 = 75 Pink
1/4 x 150 = 37.5 white

$X^{2} = \frac{(34- 37.5)^2}{37.5} + \frac{(76- 75)^2}{75} + \frac{(40- 37.5)^2}{37.5}$

$X^2=0.5067$

The degrees of freedom (DF) are calculated as number of phenotypes - 1; in this case DF = 3-1 = 2.

If we look at the Chi square table, for 2 DF and a probability of p0.05, the critical value is 5.991

Our X^2 value of 0.5067 is less than the critical value, so we do not reject the null hypothesis. The results are consistent with incomplete dominance for this trait, with pink flowers being heterozygous.

8 0

3 years ago