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WITCHER [35]
3 years ago
7

Fish first appeared: a) after the "Age of the Dinosaurs" during the Mesozoic Era. b) during the Ordovician Period of the Paleozo

ic Era. c) in the Cretaceous Period of the Mesozoic Era. d) when land plants evolved during the Carboniferous Period. e) when amphibians dominated the oceans.
Biology
2 answers:
Sveta_85 [38]3 years ago
6 0

Answer:

C. Fish first appeared when land plants evolved during the Carboniferous period

Explanation:

The age of fish was 410-360 million years ago which was called the Devonian period of the Paleozoic Era. This period immediately followed the Carboniferous Era which is 360-286 million years ago when amphibians dominate the land animals on the planet. Agnathans or jawless fishes are the first backboned fish. These fishes survived by sucking food in through the holes in their head.

Sergeu [11.5K]3 years ago
4 0

Answer:

during the Cambrian Period of the Paleozoic Era.

Explanation:

The Paleozoic is the earliest era (of three) of the Phanerozoic Eon and is composed of six geologic periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian (in that order from earliest to the latest). Fish first appeared about 530 million years ago during the Cambrian explosion.

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Extinction of species reduces the number of different species in ecosystems, hence lowering the diversity of living things.
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A different DNA ladder from NEB (Cat #N3200L) comes as 500 uL of a 1000 ug/mL solution and is not pre-mixed with the 6 X DNA loa
JulijaS [17]

Answer:

4 ul Loading Buffer + 19.70 ul dH2O + 0.30 ul DNA Ladder

Load 12 ul on the gel.

Explanation:

DNA Ladder concentration = 1000 ug/ml

1000 ug DNA in 1 ml DNA Ladder solution →    150 ng DNA = 0.15 ug DNA in..... 0.00015 ml = 0.15 ul DNA Ladder solution

6x DNA Loading Buffer → it has to be diluted by an equal volume 6 times (1 ul LB + 1 ul distilled H2O)

An appropriate volume to load on an average agarose gel is 12 ul, so:

2 ul Loading Buffer + 9.85 ul dH2O + 0.15 ul DNA Ladder = 12 ul

But since 0.15 ul is a very small volume and mistakes could be made while measuring it, let's make double:

4 ul Loading Buffer + 19.70 ul dH2O + 0.30 ul DNA Ladder = 24 ul

And load half of that solution (12 ul) on the gel.

5 0
3 years ago
Clear cutting has a similar effect as controlled burning of a forest. True False
zysi [14]

The correct answer is false and here is why:

Clear cutting refers to the cutting of trees, specifically all of the trees in one select area. Replanting is not done and this leads to deforestation.

Controlled burns have a completely different affect. They burn the under brush to help keep the soil rich with nutrients, plus they also help to prevent large crown fires that burn down whole forests from happening.

Clear cutting is a bad thing and controlled burns are a good limiter for a forest.

4 0
3 years ago
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Humans Come From A Guy Sperm It Goes Into The Females Egg

6 0
3 years ago
Read 2 more answers
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Leona [35]

The Best-Correct Statements as it Pertains to the Control Group and Experimental Group are:

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<h3 />

What are the control and experimental group in a study?

The control group in a study is the group in which no changes are applied to the group.

In the control group, the variables are kept constant, hence, the control group is also known as the constant group.

The experimental group in a study is the group to which the treatment being studied is applied. The control group receives the treatment of the variable under study.

Hence, the group that receives the drug 911-918 is the experimental group.

Learn more about the control and experimental group at: brainly.com/question/26323529

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1 year ago
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