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Travka [436]
3 years ago
9

Which of the following explains observations?

Chemistry
2 answers:
gulaghasi [49]3 years ago
7 0
Hypotheses and theories
amid [387]3 years ago
6 0

Answer:

theories explain observations

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Name two hormones produced by the endocrine system and describe how they work with other organ systems to maintain homeostasis
Annette [7]
The 2 hormones are insulin & glucagon.

A hormone will only act on a part of the body it 'fits'. A hormone can be thought of as a key, and its target site ( i.e an organ) has specially shaped locks on the cell walls. 
If the hormone fits, then it will work.

The hormone can set off a cascade of other singling pathways in the cell to cause an immediate effect ( for instance, insulin signaling leads to a rapid uptake of glucose in muscle cells)

The endocrine system is a tightly regulated system that keeps the hormones and their effects at just the right level. One way this is achieved is through ' feedback loops'. The release of hormones is regulated by other hormones, proteins or neuronal signals.

The released hormone then has its effect on other organs. This effect on the organ feeds back to the original signal to control any further hormone release.


btw- found all this info @ the Better Health channel, an australian government health website , so if your still confused by my answer, check out this website

www.betterhealth.vic.gov.au/health/conditionsandtreatments/hormonal-endocrine-system

8 0
3 years ago
Read 2 more answers
A scientist has a container with a substance inside. At first, the molecules in the substance move away from each other. Later,
den301095 [7]

Answer:

before the substance was a gas it was a liquid.

Explanation:

3 0
2 years ago
Universal indicator solution
Lynna [10]
Shred red cabbage ~ (3/4 of a very small head)

Put the cabbage pieces in a small container ~ ( you can use a Pyrex-4-cup measure, a bowl or even a plastic zipper bag)

Cover the cabbage with very hot water. Let it sleep until the water has cooled. (somewhere between lukewarm and room-temperature) 

The purple liquid you've made is your indicator. 
Pour it into a container and compost the cabbage.

Now look for substances that may be acids or bases. 
Liquids are good, like fruits. 

You can also use solids around for baking are good too. (such as baking soda, salt, sugar, cream of tartar...)

Get containers for mixing (such as tea cups, because they are small, shallow and white inside)

Pour the indicator into the tea cups and add an acid or base.

Lemon juice, rice wine vinegar, and apple cider vinegar, turn the cabbage-water indicator into a pink.

Orange juice or fresh oranges (same thing) turn the cabbage-water indicator into an orangish-pinkish color. 

Baking soda turns the cabbage-water indicator blue.

Milk (non-fat) turns the cabbage-water indicator turn opaque and milky, yet purple.

An egg white (which won't get into the solution immediately until after a lot of stirring) turns the cabbage-water indicator blue.

Hint:
Bases mostly turn the indicator towards blue-ish colors such as purple, light blue, dark blue, opaque blue...

Acids mostly turn the indicator towards pink-ish colours such as orange-ish pink, floral pink...

(You'll have to keep on testing the cabbage-water indicator in after a day or two to see if the indicator quality persists or degrades.
6 0
3 years ago
Read 2 more answers
What is the average atomic mass of hafnium given the following abundance information on the isotopes?
Goryan [66]

Answer:

178.55

Explanation:

176 × 0.05+ 177 × 0.19 + 178 × 0.27 + 179 × 0.14 + 180 × 0.35 = 178.55

7 0
3 years ago
If 5.0 moles of C3H8 react, how many molecules of water are formed?
artcher [175]
Balance Chemical Equation for combustion of Propane is as follow,

                         C₃H₈  +  5 O₂    →    3 CO₂  +  4 H₂O

According to equation,

              1 mole of C₃H₈ on combustion gives  =  4 moles of H₂O
So,
        5 moles of C₃H₈ on combustion will give  =  X moles of H₂O

Solving for X,
                                    X  =  (5 mol × 4 mol) ÷ 1 mole

                                    X  =  20 moles of H₂O

Calculating number of molecules for 20 moles of H₂O,
As,
                        1 mole of H₂O contains  =  6.022 × 10²³ molecules
So,
                20 moles of H₂O will contain  =  X molecules

Solving for X,
                                 X  =  (20 mole × 6.022 × 10²³ molecules) ÷ 1 mol

                                 X  =  1.20 ×10²⁵ Molecules of H₂O
8 0
3 years ago
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