Unit 2 - The Genetics of Life - 9th Grade

DNA and RNA

I am a nucleic acid

RNA

I am usually single-stranded

RNA

I am generally found both inside and outside of the nucleus [in eukaryotic cells]

DNA

I am arranged as a double helix, and my shape is often described as a “twisted ladder”

DNA and RNA

I include bases guanine, cytosine, and adenine

DNA and RNA

Each of my nucleotides includes a phosphate, sugar, and base

RNA

I include the base uracil

DNA

I include the base thymine

DNA

I generally remain in the nucleus [in eukaryotic cells]

DNA

I have the sugar deoxyribose

DNA

I am made up of nucleotides

RNA

I have the sugar ribose

mRNA stands for:

mRNA stands for:

rRNA stands for:

Ribosome RNA

tRNA stands for:

Transfer RNA

General Function of mRNA

Carry genetic instructions from DNA to ribosomes to synthesize proteins.

General Function of rRNA

To form the core structure of ribosomes.

General Function of tRNA

Transfers amino acids [to area of protein synthesis]

Genetics (definition)

The study of heredity and the variation of inherited characteristics

Heredity (definition)

The passing down of genetic traits from parents to offspring

What do we need to know in order to understand heredity?

Chromosomes, DNA, Genes, and Traits

Chromosome (definition)

A threadlike structure of nucleic acids and protein, carrying genetic information in the form of genes

Cellular DNA is the ___ source for making ___ in the cell

information; proteins

DNA codes for:

Traits

Nucleotide = 5-carbon ___, Phosphate, ___ Base

sugar; nitrogen

Nitrogen Bases =

Adenine, Thymine, Cytosine, and Guanine

(DNA) A pairs with

T

(DNA) C pairs with

G

The process of Protein Synthesis includes:

Transcription and Translation

Transcription =

DNA —> RNA

Translation =

RNA —> Protein

Where does transcription happen?

Nucleus

Where does translation happen?

Ribosome (rRNA), in the cytoplasm

(Translation) Codon:

each 3 / every 3

***The shape of a protein molecule is important to its function (how it works). If a protein doesn’t have the correct shape, it won’t work well or won’t work at all.***

READ IT!!!!!!!!!!!

(Mutations) Change in the code of ___ which effects ___ synthesis

DNA; protein

(Mutations) Source of genetic ___ (differences)

variation

(Mutations) Completely ___

random

(Mutations) Can be ___, ___, or cause no effect

good; bad

Mutations fall into what two basic categories?

Gene mutations and Chromosomal mutations

What is the main difference between gene mutations and chromosomal mutation?

Gene mutation is a change of the nucleotide sequence of a gene whereas chromosomal mutation is a change of the structure or number of chromosomes

Mutation (definition)

A permanent change that occurs in a DNA sequence

(Types of Mutations) Mutation major reason(s): 1

Environmental radiation (x-Rays and UV Rays), chemical, smoking, etc.

(Types of Mutations) Mutation major reason(s): 2

Inherited: may inherit mutations from parents reproductive cells (egg and sperm)

(Types of Mutations) Mutation major reason(s): 3

Due to mistakes when DNA is copied

(Types of Mutations) Mutation major reason(s): 4

Random mutations

Do eukaryote cells have a nucleus?

Yes

Do prokaryote cells have a nucleus?

No

Finish the sequence for DNA: ATGC

TACG

Finish the sequence for RNA: ATGC

UACG

Genes (definition)

sequence of DNA that codes for a protein and thus determines a trait; factor that is passed from parent to offspring

Allele (definition)

one of a number of different forms of a gene, they are what directly specify what traits you have

Traits (definition)

specific characteristics of an organism

Fill(Genes, Traits, and Alleles:) Fill in the blank: The ___ is determined by the alleles……meaning the trait is what we finally see as the phenotype (___)

trait; physical appearance

Traits include things like:

your hair color, height, and eye color