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4 years ago

Calcium has an atomic number of 20 and an atomic mass (weight) of 40. Therefore, we know that calcium has

2 answers:

7 0

It would have 20 protons, 20 neutrons, and 20 electrons. Protons and electrons are USUALLY (I say usually because of the different types of atoms) the same as the atomic number. To find neutrons you take the atomic mass minus the atomic number. 40-20=20

maks197457 [2]4 years ago

4 0

It would have 20 protons, 20 neutrons, and 20 electrons.

You might be interested in

(a) Identify the most likely mode of transport across the membrane for substance L. Explain how information provided helps deter

Viefleur [7K]

Active transport occurs against the electrochemical gradient. It needs energy to move molecules from the lower concentration side to the higher concentration side. The mode of transport is active transport. 

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There are three main different types of transport across the membrane

Simple diffusion ⇒ Does not need energy to occur
Facilitated transport ⇒ Does not need energy to occur
Active transport ⇒ Needs energy to occur

Active transport is the transport of molecules that move against the electrochemical gradient, so it does need energy to happen.

Molecules move from the lower concentration side to the higher concentration side of the membrane.

Carrier proteins are in charge of active transport. The needed energy might proceed from the ATP molecules or the membrane's electric potential.

In the exposed example, a scientist wants to determine how substance L enters a cells in a culture.

The cells maintain a 120 mM intracellular concentration of substance L.

Varying external concentrations of substance L (10 to 100 mM) in culture medium (Table 1).

Table 1. Rate of entry of substance L into mammalian cells in culture

External concentration of substance(mM) Rate of entry of substance L

10 5%

20 25%

30 45%

40 65%

50 80%

60 90%

70 95%

80 100%

90 100%

100 100%

Now, we need to identify the most likely mode of transport across the membrane for substance L, and explain how information provided helps determine the most likely mode of transport.

We know that the intracellular concentration is 120mM.

As we can see, this concentration exceeds all of the culture media concentrations. Yet, the substance keep moving into the cell.

As the concentration inside the cell is always higher than the concentration outside, we can assume that this is not passive transport because the molecule transport is going against its concentration gradient.

Hence, the remaining option is active transport. And as said before, we can see it because the substance keeps crossing the membrane toward the cell interior despite its concentration being higher in the interior of the cell than in the exterior.

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6 0

3 years ago

Which of the following is considered assimilation in the carbon cycle?

kicyunya [14]

Answer: C. A plant absorbing carbon dioxide during photosynthesis

A plant absorbing carbon dioxide during photosynthesis can be considered as assimilation in the carbon cycle. 

Explanation:

The process of carbon fixation is called assimilation in carbon cycle. In the atmosphere carbon occurs in the form of carbon dioxide. 

By the process of carbon fixation this carbon dioxide is converted into carbon compounds and these act as source of energy in an ecosystem.

Photosynthesis is an example of carbon fixation process. Other processes like chemo-synthesis also fix carbon. Majority of carbon fixation takes place in marine environments. 

7 0

4 years ago

The central nervous system includes all of the following except: brain spinal cord nerves that reach the tissues in limbs cerebe

il63 [147K]

Answer:

My answer is the CNS consist of the brain and the spinal cord nerves but not cerebellum.

3 0

3 years ago

What is another name for major depressive disorder?:

NNADVOKAT [17]

I believe the answer to your question is c

4 0

3 years ago

What are the differences between a light microscope and a scanning electron microscope?

mr Goodwill [35]

Answer:

There is a great difference between light and scanning electron microscope. The source of illumination is light rays in light microscope while in scanning electron microscope electrons are the source of illumination.

The resolving and magnification power of scanning electron microscope is much greater than that of a light microscope. The magnifying power of a light microscope is 1000X and of electron microscope is 10,00,000X.

In light microscope image is seen through the eyepiece while in scanning electron microscope it is seen on a fluorescent screen. Even small specimens up to 0.1 micrometers can be seen by scanning electron microscope which is not possible to see by light microscope.

8 0

3 years ago