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Agata [3.3K]
3 years ago
7

Explain why life on land was difficult for early plants

Biology
1 answer:
kicyunya [14]3 years ago
8 0
Because the soil didn't have the same nutrients it has now due to lack of decomposition of other plants and animals.
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How many rounds of mitosis produce 64 daughter cells?(1 point)
Gre4nikov [31]

The correct answer is 6 rounds.

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Why are the nuclear reactions that occur in the center of the Sun critical to life on Earth?
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The simple answer is that the sun, like all stars, is able to create energy because it is essentially a massive fusion reaction. ... Technically known as nuclear fusion, this process releases an incredible amount of energy in the form of light and heat.

Explanation:

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In this activity, you will explore how DNA microarrays are being used as a tool for studying-and possibly treating--cancer 1 2 3
sineoko [7]

Microarray data attached

Answer:

B, D, E are consistent with the data in the microarray

Explanation:

A) False, if you look at the microarray graph, Gene K is red on the right side of the graph (where patients in group II are) and generally more blue on the left side where group I patients are, meaning it is less expressed

B) This is true, look for example at gene F, individual 3 expresses it strongly, whereas individuals 6 and 7 are quite low.

C) No - microarray data looks at the expression of genes, not the genes themselves.

D) Yes, you can see that generally, genes B-Q are highly expressed in group II patients but not group I. In contrast, genes F-U are not expressed in group II but more expressed in group I.

E) Yes, although the data is not always consistent, there are clear patterns in group II patients not present in group I.

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3 years ago
If two genes are found on different chromosomes, or if they are far enough apart on the same chromosome that the chance of a cro
nika2105 [10]

Complete question:

A wild-type tomato plant (Plant 1) is homozygous dominant for three traits: solid leaves (MM), normal height (DD), and smooth skin (PP).

Another tomato plant (Plant 2) is homozygous recessive for the same three traits: mottled leaves (mm), dwarf height(dd), and peach skin (pp).

In a cross between these two plants (MMDDPP x mmddpp), all offspring in the F1 generation are wild type and heterozygous for all three traits(MmDdPp).

Now suppose you perform a testcross on one of the F1plants (MmDdPp x mmddpp). The F2 generation can include plants with these eight possible phenotypes:

solid, normal, smooth

solid, normal, peach

solid, dwarf, smooth

solid, dwarf, peach

mottled, normal, smooth

mottled, normal, peach

mottled, dwarf, smooth

mottled, dwarf, peach

Assuming that the three genes undergo independent assortment, predict the phenotypic ratio of the offspring in the F2 generation.

Answer and Explanation:

<u>Cross 1:</u>

Parental) MMDDPP  x  mmddpp

F1) MmDdPp

<u>Cross 2</u>: <em>Testcross</em>

Parental) MmDdPp   x   mmddpp

Gametes) MDP   MdP   MDp  Mdp   mDP   mdP   mDp  mdp

                 mdp   mdp   mdp   mdp   mdp   mdp   mdp   mdp

Punnet Square)

              mdp            

MDP     MmDdPp

MdP     MmddPp

MDp     MmDdpp

Mdp     Mmddpp

mDP     mmDdPp

mdP     mmddPp

mDp     mmDdpp

mdp      mmddpp    

F2) 8/64 = 1/8 MmDdPp, solid leaves, normal height, smooth skin

     8/64 = 1/8 MmddPp,  solid leaves, dwarf height, smooth skin

     8/64 = 1/8 MmDdpp, solid leaves, normal height, peach skin

     8/64 = 1/8 Mmddpp,  solid leaves, dwarf height, peach skin

     8/64 = 1/8 mmDdPp, mottled leaves, normal height, smooth skin

     8/64 = 1/8  mmddPp,  mottled leaves, dwarf height, smooth skin

     8/64 = 1/8  mmDdpp,  mottled leaves, normal height, peach skin

     8/64 = 1/8  mmddpp,  mottled leaves, dwarf height, peach skin

Another way of predicting the phenotypic ratio of the offspring in the F2 generation is by performing a testcross for each gene by separately and then multiplying their genotypic proportions. This is:

<u><em>Leaves Gene</em></u>

Parental) Mm  x  mm

Gamtes) M  m    m   m

Punnet Square)        M     m

                       m    Mm   mm

                       m    Mm   mm

F2) 1/2 Mm

      1/2 mm

<u><em>High Gene</em></u>

Parental) Dd  x  dd

Gamtes) D  d    d   d

Punnet Square)       D     d

                       d     Dd    dd

                       d     Dd    dd

F2) 1/2 Dd

      1/2 dd

<u><em>Skin Gene </em></u>

Parental) Pp  x  pp

Gamtes) P   p   p   p

Punnet Square)       P    p

                          p   Pp   pp

                          p   Pp   pp

F2) 1/2 Pp

      1/2 pp

To get the phenotypic ratio of the offspring we multiply the genotypic proportion for each trait by the genotypic proportions of the other two traits, like this:

  • For plants with solid leaves, normal height, smooth skin

solid leaves ratio -> 1/2

normal height ratio -> 1/2

smooth skin ratio -> 1/2

MmDdPp ratio: 1/2 x 1/2 x 1/2 = 1/8

  • For plants with solid leaves, dwarf height, smooth skin

MmddPp ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8

  • For plants with solid leaves, normal height, peach skin

MmDdpp ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8

  • For plants with solid leaves, dwarf height, peach skin

Mmddpp ratio:  1/2 x 1/2 x 1/2 x 1/2 = 1/8

  • For plants with mottled leaves, normal height, smooth skin

mmDdPp  ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8  

  • For plants with mottled leaves, dwarf height, smooth skin

mmddPp ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8

  • For plants with mottled leaves, normal height, peach skin

mmDdpp ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8  

  • For plants with mottled leaves, dwarf height, peach skin

mmddpp  ratio: 1/2 x 1/2 x 1/2 x 1/2 = 1/8                    

3 0
3 years ago
Why does the story of spontaneous generation illustrate the limitation of science?
VLD [36.1K]

The story of spontaneous generation illustrates that science is capable of doing exactly what it is supposed to do: observe nature and eliminate theories that contradict observations. In this case, the theory that (for instance) flies form spontaneously out of decaying meat was successfully falsified.

7 0
3 years ago
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