Biology 3/4 Cells & Nucleic Acids

What are cells

The smallest building blocks of life

What is the purpose of nucleic acid

it is the blueprint/instructions which codes for protein

What is the function of Nucleic Acid

it is the genetic instruction of the cell

What determines how a cell develops

The packing of large polymers in the nucleus to store information determines how a cell develops as they encode for proteins that are responsible for a specific function

polymer

large chain of molecule made of small repeating subunits (monomers)

Types of nucleic acids

DNA and RNA

What does DNA stand for

Deoxyribose nucleic acid

what does RNA stand for

Ribonucleic Acid

nucleotide

small repeating subunit (monomers)

draw and label a basic diagram of nucleotides

phosphate group, 5 carbon sugar, Nitrogenous bases

What changes in a nucleotide

the nitrogenous bases

What are the types of nitrogenous bases write them in pairs and list them as DNA, RNA or both

Adenine + Thymine (DNA), Cytosine + Guanine (Both) , Adenine + Uracil (RNA)

What differentiates DNA and RNA

Different shapes/arrangement therefore different functions

Nucleotides may be different

How are nucleotides joined together to create a polymer

Condensation polymerisation, which is a reaction between nucleotides that allows the nucleic acid chain to build up

Condensation

Water is formed as a byproduct

Polymerisation

Creation of a polymer ( joining of monomers)

What bond are nucleotides linked together by

Phosphate bonds, which are strong covalent bonds

What forms the backbone of DNA

Sugar phosphate backbone

Why is numbering the carbons important

rovides a universal map of a molecule's structure.

What is each number of the carbons

1’ attaches to nitrogenous base

3’ attaches to the phosphate of the adjacents Nucleotide

5’ attaches to the phosphate of the same nucleotide

How are DNA strands aligned

Antiparrallel

Where is DNA found

In the nucleus of the cell

How is DNA packed in humans

in humans it is packed as 46 chromosomes which contain genes

What do the chromosomes consist of

long DNA strands tightly coiled around histone proteins which allows them to accommodate large amounts of DNA

What is DNA made of

phosphate Deoxyribose sugar, Nitrogenous bases

What is the structure of DNA

double stranded double helix

How are the double strands held together

Via a hydrogen bond which binds complementary bases

What is the structure of RNA

single stranded

What is RNA made of

Ribose sugar

Phosphate group

Nitrogenous bases (uracil replaces thymine)

What are thye types of RNA

mRNA - messeger RNA

tRNA - Transfer RNA

rRNA - Ribosomal RNA

What does mRNA do

carries copies of genetic instructions from DNA to ribosome

purpose of mRNA

so DNA doesnt get damaged, DNA is permanent, DNA is too large

What does tRNA do

carries specific amino acids in their correct order to the ribosome

What does rRNA do

forms the majority of the structure of the ribosome

genes

a sections of DNA that codes for a protein

WHat is the process by which a protein is made form a gene called

Gene expression

draw prokaryotic gene structure

draw eukaryotic gene structure

What are the components of genes

Exons, Introns, Promoter, Operator, Terminator

Exons

Coding region

introns

non-coding region

promoter

start of the gene

operator

regulating sequence

terminator

end of gene

What are the characteristics of genetic code

Universal

Triplet

Degenerate

Universal

the same codons code for the same amino acids in all organisms

triplet

3 bases code for 1 amino acid

Degenerate

more than one codon can code for the same amino acid