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4 years ago

Which vertebrate class is considered to be the first that was entirely terrestrial?

2 answers:

7 0

Reptilia.
Reptiles were the first animals to develop shelled eggs, meaning they could be laid on land rather than in water as is necessary for the shell-less eggs of amphibians and fish. They also developed dry, scaly skin to prevent the moisture loss amphibians experience through their moist, permeable skins when on land.

Cloud [144]4 years ago

6 0

The first entirely terrestrial vertebrate class totally independent from the aquatic habitat is the class reptilia.

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The use of a grass filter _____

kakasveta [241]

Answer:

buffer zone

Explanation: a small(ish) strip of land that isn't sprayed between the cultivated plot and the water to filter out the chemicals and stop it from reaching the water

8 0

3 years ago

Read 2 more answers

HELP PLEASE ASAP. A runner travels 400 meters in 80 seconds, what is the runner’s average speed?

RideAnS [48]

Answer:

v = 5 m/s

Explanation:

Given that,

The distance covered by a runner, d = 400 m

Time, t = 80 sec

We need to find the runner's average speed. It is equal to total distance covered divided by time taken. It can be given by:

$v=\dfrac{d}{t}\\\\v=\dfrac{400\ m}{80\ s}\\\\v=5\ m/s$

So, the runner’s average speed is 5 m/s.

3 0

3 years ago

What part of the hair extends from the bulb and the shaft?

igor_vitrenko [27]

Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Strands of hair originate in an epidermal penetration of the dermis called the hair follicle. The hair shaft is the part of the hair not anchored to the follicle, and much of this is exposed at the skin’s surface. The rest of the hair, which is anchored in the follicle, lies below the surface of the skin and is referred to as the hair root. The hair root ends deep in the dermis at the hair bulb, and includes a layer of mitotically active basal cells called the hair matrix. The hair bulb surrounds the hair papilla, which is made of connective tissue and contains blood capillaries and nerve endings from the dermis.

8 0

3 years ago

14). During the early 1700’s, a small group of pacifist Protestants fled Germany to avoid religious persecution. This group, the

abruzzese [7]

A) In the Dunker population, the frequency of IB allele is 0.3 and the frequency of i allele is 0.4. In the general population, the frequency of IB allele is 0.1 and the frequency of i allele is 0.5.

If:
$I^{A}$ - the frequency of IA allele
 $I^{B}$ - the frequency of IB allele
 $i$ - the frequency of i allele

Then:
 $I^{A} I^{A}$ + $I^{A} i$ - the frequency of individuals with A blood type
 $I^{B} I^{B}$ + $I^{B} i$ - the frequency of individuals with B blood type
 $ii$ - the frequency of individuals with O blood type

Let's first take a look on the Dunker population:
$I^{A} = 0.3$
$ii=0.16
$

Since there is only one possible genotype for O individuals - ii - the frequency of the allele i is square root of the frequency of O individuals:
 $i= \sqrt{ii}$
⇒ $i = \sqrt{0.16}$
⇒ $i=0.4$

Now, we have the frequencies of two alleles ( $I^{A}$ and $i$ ). To calculate the frequency of $I^{B}$ allele, we will use the formula:
 $I^{A} + I^{B} + i = 1$
⇒ $I^{B} = 1- I^{A} - i$
⇒ $I^{B} = 1-0.3-0.4$
⇒ $I^{B} = 0.3$

Now, in the general population:
$I^{A} = 0.4$
$ii=0.25$

Similarly to the work for the Dunker population:
 $i= \sqrt{ii}$
⇒ $i = \sqrt{0.25}$
⇒ $i=0.5$

$I^{A} + I^{B} + i = 1$
⇒ $I^{B} = 1- I^{A} - i$
⇒ $I^{B} = 1-0.4-0.5$
⇒ $I^{B} = 0.1$


b) A founder effect is a result of geographical separation of a few individuals from the original population. Those founding individuals will form a new population. The Dunker population was not only geographically separated, but also genetically. The group interbreeding was present resulting in increasing those allele frequencies that were the most common in the founding population. In this case, the most individuals from the founding population had B blood type.

6 0

4 years ago

Which of the following would be the most likely reason some minorities may tend to underutilize therapeutic treatment? lack of t

Artist 52 [7]

Answer:

Explanation:

3 0

3 years ago