cell membranes

Question 1

difference between carrier proteins and channel proteins

Answer 1

Channel proteins are pores which facilitate diffusion of large polar molecules from high to low conc. they open and close to control the échange if ions

Carrier proteins change shape of the inside to transport the molecule

Question 2

How does active transport use carrier proteins

Answer 2

AT occurs from low to high conc
Energy required by ATP for carrier protein to chnage shape to transport the molecule
(ATP hydrolysed to release energy)

Question 3

What are the two mononucleotides

Answer 3

DNA
RNA

Question 4

Differences between DNA& RNA

Answer 4

Dna has Penrose sugar deoxyribose (oh)
RNA has Pentose sugar ribose (h)

RNA Is single stranded
DNA is double stranded

RNA has bases ACGU
DNA has bases ACGT

Question 5

3 components of nucleotides

Answer 5

Penrose sugar ( deoxyribose or ribose )
Phosphate group
Nitrogenous bases

Question 6

Which two bases are purine and why
Which are pyrimdine and why

Answer 6

Adenine and guanine - becuase they hage double ring structure

Thymine uracil and cytosine becuase they are single ring structures

Question 7

How are polynucleotides formed

Answer 7

Condensation reactions occur between nucleotides. It occurs between the phosphate group of the below and Penrose sugar from the one above. An ester bond is formed. A condensation reactions between two nucleotides is called a phosphodiester bond. Results in a sugar phosphate backbone