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mart [117]
3 years ago
14

What were the first artificial christmas trees made from

Biology
1 answer:
snow_tiger [21]3 years ago
6 0
Germany during the 19 century
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What can be visualized as a series of vertical lines around the Earth?
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Answer : D the prime meridian
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Which of the following is not a true statement comparing exoskeletons and endoskeletons?
nordsb [41]

Answer:

Exoskeletons provide less mechanical leverage.

Explanation:

There are two types of skeleton in living beings: the endoskeleton (which vertebrates possess, is lined with epithelial tissue and has bones and cartilage) and the exoskeleton, a skeletal structure that is located outside the body of the living being. , is an external skeleton. They are common in invertebrate animals, which have no internal bone structure.

The exoskeleton is a tough but flexible outer layer, not formed by bones, unlike the vertebrate endoskeleton. Its function is mechanical, chemical and biological protection, avoid excessive water loss, muscle support and serves as a connecting point for legs, wings and other appendages. However, this type of skeleton provides less mechanical leverage.

On the other hand, the endoskeleton is the name given to the internal skeleton, which is inside the body. This body structure is mainly seen in vertebrate animals and has the function of supporting and moving the body, as well as protecting some internal organs. Unlike exoskeleton, the endoskeleton provides more mechanical leverage.

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3 years ago
Particular life cycle.
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the sperm fertilizing the egg

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What happens to cause the tissue around a cut to become swollen, red, and painful?
insens350 [35]

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chemicals are expelled from the white blood cells into the wound site, and this is what causes the redness and warmth.

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In 1985 a biologist counted 750 pine trees in a 250 hectare forest. Using similar counting techniques, the biologist counted 1,2
Alisiya [41]

Answer:

Suppose that we have a given function f(x)

The average rate of change of the function between two values x₁ and x₂ is given by:

r = \frac{f(x_2) - f(x_1)}{x_2 - x_1}

a) We want to find the average (rate) of change on the size of population from 1985 to 1995.

We have that:

f(1985) = 750

f(1995) = 1500

Then we have:

r = \frac{1500 - 750}{1995 - 1985}  = 750/10 = 75

This means that the population of trees increases, in average, at a rate of 75 trees per year.

b) What is the density of trees each year that they were counted?

This will be equal to the quotient between the number of trees and the area.

1985: number of trees = 750 pines

         area = 250 ha

Then the density is:

D(1985) = (750 pines)/(250 ha) = 3 pines/ha

So 1985, there were 3 pines per hectare.

1990: number of trees = 1250 pines

         area = 250 ha

Then the density is:

D(1990) = (1250 pines)/(250 ha) = 5 pines/ha

1995: number of trees = 1500 pines

         area = 250 ha

The density is:

D(1995) = (1500 pines)/(250 ha) = 6 pines/ha

3) now we want to get the average change between 1985 and 1995 in the density, this will be:

r = \frac{D(1995) - D(1885)}{1995 - 1985}  = \frac{6 pines/ha - 3pines/ha}{10}  = 0.3 pines/ha

So, on average, each year the number of pines per hectare increases by 0.3

7 0
3 years ago
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