The 2nd and 4th answer choices sound the best to me. I personally would go for the 2nd one, explaining that the fossils of fish K and fish R and Y are similar. If you get the question wrong, I am VERY sorry. :(
The cell membrane is selectively permeable, allowing only certain substances to pass through. Passive transport is a way that small molecules or ions move across the cell membrane without input of energy by the cell. The three main kinds of passive transport are diffusion, osmosis, and facilitated diffusion.
Answer:
A sugar called deoxyribose.
Explanation:
DNA is made up of molecules called "nucleotides". These are:
- A phosphate group
- A pentose sugar [deoxyribose]
- A nitrogen-containing base [adenine, thymine, guanine and cytosine]
Thus the first option is the right answer.
Reasons why the other options are wrong:
"A plasma called haemoglobin" is wrong as plasma and haemoglobin are related to the blood.
"A chemical called nucleic acid" is wrong as it is not what DNA's made up of. DNA and RNA are nucleic acids themselves.
"An acid called chlorophyll" is wrong as chlorophyll is related to plants.
It forms when gas in stiff magma expand rapidly and the walls of the gas bubbles explode into any, glasslike slivers