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3 years ago

Please help (select all that are true)

Biology

2 answers:

kari74 [83]3 years ago

8 0

Answer:

All are correct, except that it produces gametes

Explanation:

Only in meiosis gametes come together to fertilize. In mitosis it only uses somatic cells which are body cells and no gametes. Gametes in humans are only found in spermatozoa and ova (sperm and egg). Gametes are not somatic cells.

Mamont248 [21]3 years ago

3 0

Answer:

All are correct except that mitosis does not create a new variations of cells rather it produces exact copies of the original cell.

Explanation:

Mitosis is a cell division process where by the cell divides to produce exact or identical copies of itself. Gametes are produced by mitosis and after fertilization a diploid zygote is created.

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How do scientists measure wildlife population such as rabbits?

faust18 [17]

They plot out a given area, such as 500 acres. They pick a section, maybe 100' X 100' square, and set live traps.

After catching the rabbits, they do a count and note sex, age, health. and size, then turn them loose. The number of rabbits caught, times how many 100' X 100' sections there are in 500 acres, gives them the approximate amount of rabbits in that 500 acre area.

This kind of thing is done for most animal populations, except for those that can't or shouldn't be caught. Those animals are often counted by observation or by photography and then multiplied by the given area as I said.

-- From Google.

3 0

3 years ago

Which of the following is digested first? protein starch fat sugar

Reika [66]

Answer:
Starch

Explanation:
Digestion begins in the mouth. The teeth break down food from chewing through mechanical digestion.

Chemical digestion also begins in the mouth. Saliva moistens food, but it contains an important enzyme called amylase. This enzyme breaks down starch into simple sugars.

So, the first compounds that are digested are starch.

7 0

3 years ago

_____ that are not reabsorbed drift out of the synaptic gap, through diffusion. This is how the synaptic gap is cleared, in prep

BigorU [14]

Answer;

-Nuerotransmitters

Neurotransmitters that are not reabsorbed drift out of the synaptic gap, through diffusion. This is how the synaptic gap is cleared, in preparation for the next release of a new batch of these chemical messengers.

Explanation;

-The majority of neurotransmitters drift across the synaptic gap and come into contact with receptor sites of the receiving neurons dendrites. Receptor site is the location where neurotransmitters attach on the receiving side of the synaptic gap. Because there are a variety of neurotransmitters a variety of receptor sites also exist.

-It is necessary for the right neurotransmitter to fit a corresponding receptor site to convey the message.

-When the neuro transmitters latch onto the receptors of the dendrites of the receiving neuron tiny gates in the receiving cells membrane fly open ushering positively charged particles into the cell and restarting the cycle of action potential.

-The firing of one neuron contributes to the potential for neighboring neurons to fire as a result of its chemical message. Reuptake process by which neurotransmitters are reabsorbed by the sending terminal bud. Neurotransmitters that are not reabsorb drift out of the synaptic gap through diffusion

6 0

3 years ago

Why is the moon abiotic?

andrezito [222]

The moon is abiotic because it is a non living thing

4 0

3 years ago

Read 2 more answers

PLEASE HELP I only have tomorrow morning to get my grade up.

Deffense [45]

Answer:

B. The total amount of light in the spectrum tells us the star’s radius.

Explanation:

The effective temperature of a star can be determined by means of its spectrum¹ and Wien's displacement law.

Since stars behave in a local way as a blackbody, it will take the wavelength at which is the peak of emission greater in the continuum (see the image below).

Then, the maximum peak of emission () will be replaced in the next equation of the Wien's displacement law:

(1)

Where T is the effective temperature of the star.

Bodies that are hot enough emits light as consequence of its temperature. For example, a iron bar in contact with fire will start to change colors as the temperature increase, until it gets to a blue color, which its know as Wien's displacement law. Which establishes that the peak of emission for the spectrum will be displaced to shorter wavelengths as the temperature increase.

The same scenario described above can be found in the stars, a star whit higher temperature will have a blue color and one with lower temperature, a red color.

Since star does not have the same size, they have different brightness, That is because the photons have a free mean path greater in a bigger radius.

So a star brightness is a consequence of its radius.

Spectral lines will be shifted to the blue part of the spectrum1 if the source of the observed light is moving toward the observer, or to the red part of the spectrum when it is moving away from the observer (that is known as the Doppler effect).

By using that shift in the spectral lines, the Doppler velocity can be determined.

(2)

Where is the wavelength shift, is the wavelength at rest, v is the velocity of the source and c is the speed of light.

D. When a photon is absorbed by an electron in an atom of a particular element in the star photosphere, the electron will be pass to a higher state, when it comes back to the ground state, a photon will be emitted again. If the emitted photon does not go in the same direction of the incident photon an absorption line will be created in the spectrum of the star.

This patterns of spectral lines in the spectrum of the star are compared with the patterns that are got by lamps of that element in a laboratory.

Key term:

¹Spectrum: decomposition of light in its characteristic colors (wavelengths).

7 0

3 years ago