DNA & Genetics Flashcards
Smallest to largest - Genetics
DNA
Genes
Chromosomes
Genome
Nucleus
Cell
Tissue
Organs
Human Body
DNA definition
Deoxyribonucleic acid (DNA) is a molecule that contains he biological instructions to make each species ad individual unique. DNA, along witht he instructions it contains, is passed from adult organisms to their offspring during reproduction. DNA is found in the nucleus of a cell. DNA tells amino acids how to form into proteins. It’s made up of nucleotides. It self replicates.
Gene definition
A gene is the basic physical and functional unit of hereditary. Genes, which are made up of DNA, act as instructions to make molecules called proteins. A gene is a special stretch of DNA that make code for something specific. It’s information for cells. Genes make proteins that interact together. Size and shape of a protien depends on the length and sequence of the gene.
Chromosomes definition
Chromosomes are thread like structures located inside of the nucleus of an animal or a plant cell. Each chromosome is made up of protein and single molecule of deokyribonucleic acid. Passed from parent to offspring, DNA contains specific instructions that make each type of living creature unique. It is an entire chain of DNA along with stabalizing protiens. Chromosome fibre holds small histones that carry DNA. It’s packaged tightly when reproducing and splits in half when it’s not.
Genome definition
An organism’s complete set of DNA, including all its genes. Each genome contains all the information needed to build and maintain that organism.
Alleles definition
Determine the distinct traits that can be passed to offspring. Genes exist in alternate forms called alleles.
Gene - eye colour
Allele - blue, green, brown, etc.
Alleles are different versions of a gene.
Rosalind Franklin
Took the first x-ray pictures of DNA. This helped scientists determine the shape of DNA.
James Watson & Francis Creek
Built the first DNA model. Given credit for determining the double helix shape.
Structure of DNA
A strand of DNA is made of a monomer called nucleotides. Each nucleotide is made up of three parts: sugar (deoxyribose), phosphate, and a nitrogen base which always binds to the sugar.
Maurice Wilkins
Known for contributions to discovery of DNA molecular structure.
Linus Pauling
Worked out structure of proteins and involved in race to find structure of DNA.
Amino Acids
Tiny little chemicals found in the cytoplasm of a cell and are known as the building blocks of life. They connect to create proteins. There’s 20 different kinds.
Smallest to largest
Amino acids, protein, living cells, tissue, organs, human.
RNA
Brings part of the DNA to the ribosomes to create proteins.
Cells and DNA
Cells have 46 strands of DNA which are made up of nucleotides. There is 4 different types: Adenine, Thymine, and Guanine, Cytosine.
Mutation
Any change in the nucleotide sequence of DNA/RNA.
Types of bonds
Covalent - present in the backbone of each separate nucleotide and it holds nucleotides together, it’s very strong.
Hydrogen - present in the double helix and holds the bases together. It allows them to break away.
Chargaff’s rule
Adenine always goes with Thymine
Guanine always goes with Cytosine.
Characteristic
Feature such as eye colour or wing type. It’s a broad subject.
Trait
Variation of a characteristic like blue eyes, long wings.
Heritable Characteristics
Characteristics passed from patent to offspring.
Non-heritable characteristics
Cannot be passed from parents like dyed hair.
Discrete Variation
Traits that have a defined form like a species of flowers can be either purple or white.
Continuous Variation
Very wide range of possibilities like height.
Dominant gene
Dominant version of a gene that shows through offspring even if only one parent has it.
Recessive gene.
Shows it’s specific trait when passed from both parents.
Hereditary
Transmission of one characteristic through generations.
Genotype
Genetic code of your cells, the exact pairing of alleles. Known as BB, Bb, or bb.
Phenotype
The physical expression of the genotype like the colour of the eyes. It’s not known as the code.
Homozygous Dominant
Example: AA
Takes over Homozygous recessive and heterozygous.
Homozygous recessive
Example: bb
Known as a hidden gene
Heterozygous
Takes over homozygous recessive.
Punnett squares
Shows the probability or likeliness of a genetic outcome. It’s not what it will be but what it could be.
Genetic Disorders
A genetic disorder is caused by an abnormality in an individual DNA.
Types of genetic disorders
Single gene disorders - these disorders involve mutations in the DNA sequence of single genes. As a result, the protein the gene codes for is either altered or missing.
Chromosomal disorders - in these disorders, entire chromosomes or large parts of them are missing, duplicated, or otherwise altered.
Multifactorial disorders - these disorders involve variations in multiple genes and is often coupled with environmental causes.
