A section of DNA that holds the genetic code for a protein.

A chemical substance whose structure is coded for by the genetic code in genes.

The process in which genes are copied during the first step in protein synthesis.

Produced when a mutation causes a change in the genetic sequence of a gene or non-coding section of DNA.

The physical characteristics of an organism.

Genetic variants in non-coding DNA can influence phenotype

Biology

Pupils will learn about dominant and recessive alleles, and how to use models of single gene inheritance to make predictions about the genotypes and phenotypes of offspring.

Pupils learned about flower structure, wind and insect pollination, fertilisation, seed and fruit formation and dispersal.

This unit covers the structure and function of eukaryotic and prokaryotic cells, DNA as the genetic material, and key genetic terms. It also explains protein synthesis, genetic variants, and how DNA structure affects proteins. The emphasis is on using models to explain scientific concepts.

DNA and the genome

Genes are instructions to a cell on how to produce which type of molecule?

DNA that isn’t used to determine the structure of a protein is called {{}} DNA.

A gene codes for a protein using a nucleotide sequence.

A gene is activated so that the protein it codes for is produced.

RNA polymerase binds to the non-coding DNA before a gene.

The protein coded for by a gene is produced.

What does the term 'gene expression' mean?

A section of non-coding DNA activates a gene.

RNA-polymerase enzyme binds to a section of non-coding DNA before the gene.

mRNA copy of the gene attaches to a ribosome and translation occurs.

Amino acids join together in an order determined by the mRNA to form a protein.

Put the events in the synthesis of a protein in the correct order.

Changes to the non-coding DNA nucleotide sequence can happen due to copying errors or because of environmental factors such as chemicals in cigarette smoke. What are these changes to the DNA called?

Cells constantly grow and divide leading to tumour formation.

Transcription is prevented and the protein can’t be produced.

Gene remains inactive and protein is not produced.

There are several ways changes to non-coding DNA can affect an organism's phenotype. Match the change to the description of how it can alter phenotype.

Something capable of causing a change in the genetic code.

The process of copying a gene and making mRNA.

Using the genetic code of mRNA to make a polypeptide.

The number of types of nucleotide base in DNA.

The number of nucleic acid strands in a molecule of DNA.

The number of nucleic acid strands in a molecule of mRNA.

The number of nucleotide bases in a triplet code.

Which of these is **not** a type of mutation?

Allele 1 has mutated to become allele 2.

Allele 1 code:  ATT CCG GAC TAT ATA CGC CCC.

Allele 2 code: ATT CGG GAC TAT TAT ACG CCC C.

How many mutations have there been in allele 1

A gene copy called mRNA is made in the nucleus.

The copy is small enough to get into the cytoplasm.

The sequence of bases in mRNA is read at a ribosome.

Amino acids are assembled into a sequence determined by the mRNA base sequence.

The amino acid sequence determines the 3D shape of the enzyme.

Put the statements in order to describe how a gene in the nucleus is used to make an enzyme that controls a chemical reaction in the cytoplasm.

A change in the 3D structure of a protein may lead to a change in an organism such as a different eye colour. What word do biologists use for physical characteristics such as eye colour?

Starter Quiz