In an experiment, dr. travis examined the effects of calcium intake on osteoporosis, a condition that causes an increased risk of bone fractures. the amount of calcium variable. the risk of bone . 1. a reliable an independent a dependent 2.can be changed by the participants can be changed by the researcher could change with calcium

Osteoporosis refers to an ailment characterized by reduced bone mass and loss of bony tissue that may lead to weak and fragile bones. In an experiment, Dr. Travis tested the influences of the consumption of calcium on osteoporosis, the condition that results in enhanced chances of bone fractures.  

In the given experiment, the amount of calcium is the independent variable, and the risk of bone fractures could get changed with the amount of calcium consumption.  

The amount of calcium is independent variable.

An independent variable is a variable in an experiment which is changed to see its effects on dependent variable.

In this experiment, to know about the causes of osteoporosis, the Ca level in blood or calcium intake in changed.

So the concentration of calcium will be independent variable.

The risk of bone fractures is could be changed with calcium.

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.