Bio Unit 2

DNA

Stands for deoxyribonucleic acid. It is a molecule that contains our genetic information.

Gene

A small segment of DNA located at a specific place in a chromosomes.

Chromosomes

Are c-shaped packages of DNA.

Nucleotide

It referred to as the base pairs: A:T G:C

Double Helix

The structure of a DNA molecule.

mRNA

A copy of a DNA coding strand that codes for an an amino acid(Protein).

Uracil

It takes less energy to make uracil and is easily repaired.

Protein

A molecule specific to cells that provides structure and function.

Transcription

From DNA to mRNA

Translation

From mRNA to an amino acid chain(protein)

Codon

A sequence of 3 nucleotides that codes for an amino acid.

Genome

A complete set of coded DNA.

Control Gene

Turn groups of genes on / off

Enzymes

Proteins that speed up chemical reactions.

Hormones

Proteins that tell a cell what to do.

Determines the biological sex in humans

The 23rd pair of chromosomes.

Genotype for a female and male

Female(xx), Male(xy)

Protein Synthesis

1. Transcription – DNA is copied into mRNA in the nucleus.

2. mRNA leaves the nucleus – The mRNA travels to the ribosome.

3. Translation begins – Ribosome reads the mRNA codons.

4. tRNA brings amino acids – Each tRNA matches its anticodon to the mRNA codon and adds the correct amino acid.

5. Amino acids link – A chain of amino acids (a protein) forms.

6. Protein folds and finishes – The protein detaches and folds into its final shape.

Amino Acid

Is the building block of proteins. There 20 different amino acids, 4 are essential.

Phosphate Backbones

It provides structural framework for a DNA and RNA.

Allele

Alternate forms of a single gene that determines traits.

Dominant

Observed trait of an organism that masks recessive form of a trait.

Recessive

Trait of an organism that can be masked by the dominant form of a trait.

Genotype

The genetic makeup of an organism, representing the combination of alleles in an organism.

Phenotype

The outward physical appearance of a trait, determined by their genotype and environmental factors.

homozygous

When there m are two identical alleles for a particular gene(or trait).

Heterozygous

Where there are two different alleles for a trait.

Trait

Characteristics that is inherited; can either be dominant or recessive.

Gamete

it is a male and female sex cells such as sperm and egg.

Selective Breeding

Intentional mating of organisms with desired traits to produce offspring losing with those traits.

Mendelian Traits

Traits that are passed down by dominant and recessive alleles.

Genetics

The study of heredity and the variation of inherited characteristics.

Carrier

An individual who carries and is capable of passing on a recessive allele but don’t express they’re heterozygous.

Codominant Traits

When a single gene has more than one dominant allele and is fully expressed.

Polygenic Traits

One characteristic is controlled by two or more genes.

Heredity

The passing of traits from parents to offspring.

Continuous Variation

Traits with a range of possibilities; often determined by many genes.

Discrete Variation

Traits with a finite numbers of phenotypes.

Genetic Mutation

A permanent alternation in the DNA sequence. That can have a positive, negative, or neutral effect.

Deletion Mutation

A base pair is missing.

Addition mutation

An extra base pair is added.

Substitution mutation

One base pair is replaced for another. No frame shift occur.

3 types of Genetic Mutations

1.) Deletion

2.) Addition

3.) Substitution

Mutagens

A physical or chemical agent known to change the sequence of DNA resulting in mutation.

Nature vs. Nurture debate

Whether behaviour is determined by the environment(including parental care), or if it is a result of genetics.

study of Epigenetic

Is the study of modifications of gene expression rather than alteration of genetic code itself.

Epigenetics

Gene expression is influenced by Epigenetics through his one modification that turn genes ‘up’ and ‘down’ which increase/decrease gene expression.