Biology Final Exam

genetic diseases

disease that are inherited through traits passed down from generation to generation

normal vs. cancerous cells

normal cells have enough time to grow to a large enough size (interphase) and can split apart into 2 cells that are a good size while cancerous cells don’t take enough time to grow and instead go through mitosis much faster and split into much smaller cells and divide uncontrollably causing tumors

Nucleotides

the DNA structural units of it made up of a nitrogenous base, deoxyribose sugar, and a phosphate group

Deoxyribose

* the sugar attacked to the nucleotide


* forms the sugar phosphate backbone

Phosphate

* a group attached to the sugar and nucleotide


* allows bases to be passed onto new cells

nitrogenous bases

* adenine


* cytosine
* thymine 
* guanine

purine bases

* adenine and guanine 
* has two nitrogen rings 

pyrimidine bases

* thymine and cytosine


* has only one nitrogen ring

double helix

the structure of the DNA

antiparallel strands

strands of DNA are oriented in opposite directions

5’ and 3’ orientation

* both strands have a 5’ and a 3’ but if the 3’ is on top the 5’ is on top of the other and for the bottom as well
* during DNA replication, the DNA is replicated as the 5’ side follows the 3’
* on the lagging strand ozaki fragments are the pieces of the DNA that is able to be replicated with the DNA polymerase but the lagging strand had spaces in it and the ligase fill those holes making finishing touches to the DNA

H bonds between bases

between each nitrogenous base there is a hydrogen bond

specific base pairing

* adenine matches up with thymine (use 2 hydrogen bonds)
* guanine matches up with cytosine (use 3 hydrogen bonds)

Helicase

unzips the DNA

Primase

is a primer and prepares DNA for the replication and addition of polymerase to work

DNA Polymerase

adds the corresponding nucleotide when replicating DNA

Ligase

ligase fixes breaks in the DNA and is basically making finishing touches on the lagging strand

specific base pairing

* adenine nitrogenous base pairs with thymine 
* cytosine nitrogenous base pairs with guanine

semi-conservative replication

When DNA is replicated, half of the DNA is from the OG and the other half is new and synthesized therefore, the DNA has only half of the OG DNA making is *semi-*conservative

mutations in DNA

can cause many diseases 

substitution

when one nucleotide is replaced with another one that does not match the sequence for the organism to be normally seen in chromosome

deletion

when one part of the chromosome is deleted or part of the DNA is deleted

insertion

when an extra part of the DNA is added or part there is an extra part added to the chromosome

translocation

when one part of a chromosome detaches from its original chromosome and attaches to another chromosome

Interphase

* get cell ready for split
* replicates DNA and gives necessary stuff

G1

growth of the cell (longest phase)

S

DNA is replicated

G2

growth of the cell (checks for duplicated DNA, nucleus, membranes)

(G0)

resting state of gap phase of mitosis and if there are cells not functional, they leave the cell cycle and go to a dormant state and brain cells go here too

Prophase

* chromosomes condense
* nucleic envelop starts to disappear
* centrioles separate and form separate fibers

Metaphase

* spindle fibers attach to chromosomes
* chromosome pull themselves into the center of the cell

Anaphase

* identical sister chromatids split
* individual chromosomes separate and more towards opposite poles of the cell

Telophase

* chromosomes gather at opposite ends of the cell
* 2 nucleic envelopes start to form around the chromosomes at the ends of the cell
* cell is about to divide, almost there

Cytokinesis

* cell actually officially divides into 2
* forms 2 sister cells

gene expression

* when our DNA is converted into a functional product
* the instructions of our DNA create functional products like proteins which allow the body to work

DNA to protein

mrna to trna to amino acids to protein

tumor suppressor genes

* stop cells from dividing so quickly

proto-oncogene

gene involved in normal cell growth

oncogene

* a gene that can transform a cell into a tumor cell
* mutated proto-oncogene

tumor suppressor genes role in cancer

* it stops cancer from happening as it stops cells from dividing so quickly and causes cells to have natural growth


* keeps a cell normal

pedigrees

* shows a trait move through a family of organisms
* female is circle
* male is square
* colored is affected trait

autosomal

the chromosomes that are not related to the sex of an organism the 1-22 chromosome

sex linked

* show the sex of an organism XX or XY
* the 23rd chromosome

dominant vs. recessive

dominant trait always is shown when in a heterozygous genotype and recessive is only shown with a homozygous genotype

alleles

* traits 
* different versions of traits

heterozygous vs. homozygous

* heterozygous - has different alleles and the dominant trait shows through
* homozygous - shows the trait of the said allele

genotype vs. phenotype

* geno - two alleles together showing a trait
* pheno - physical representation of trait

genetic carriers

someone who doesn’t physically show the trait but carries it

Protein Synthesis

* transfer DNA to mRNA
* take the MRA sequence and tRNA takes 3 and it make it amino acid
* makes amino acid sequence 
* sequence comes together and forms a protein

Transcription

converts DNA to mRNA

Nucleus

the transcription of converting DNA to mRNA is done in the nucleus

RNA polymerase

gives the corresponding RNA nucleotide to the DNA

specific base pairing for DNA to mRNA

* g to c
* c to g
* t to a
* a to u

mRNA

what is used to code for amino acids to ultimately code proteins

ribose sugar

5 carbon sugar found in mRNA

single stranded

mRNA is single stranded unlike DNA which is helix shaped and double stranded

uracil

* matches to adenine instead of adenine matching to thymine
* no thymine in mRNA

codon

* a thing of 3 mRNA nucleotides
* tRNA connects to this and on top of tRNA is a amino acid and the amino acids come together and form a bent messed up thing and form a protein

Translation

making a protein with tRNA and amino acids

Cytoplasm

amino acids are taken from the cytoplasm

Ribosome

tRNA leaves the ribosome to go to the cytoplasm and get a corresponding amino acid based on the codon and comes back to the ribosome to make protein

tRNA

mRNA has codon and tRNA has anti-codon so they attach and the tRNA attached the codon to themselves so that they can leave the ribosome and find the correct amino acid based on the mRNA codon on the tRNA

anticodon 

* on the tRNA
* has the corresponding nucleotides to the mRNA so it attaches

amino acids

* the building blocks to a protein 
* make a sequence then fold up and form a protein

peptide bonding

when the amino acids bond together to form a sequence and form a protein, the bond holding the amino acids together are peptide bonds

protein structure

very messy like yarn in a ball very all over the place

primary structure of proteins

linear sequence of a.a.

secondary structure of proteins

* formation of H bonds due to polar a.a.


* alpha coiling, beta pleating
* alpha helix looks like DNA helix with one strand
* beta pleating looks like a fan

tertiary structure

* infolding of hydrophobic a.a to the inside of molecule; rotation of hydrophilic a.a. to the outside of the molecule
* 3-dimensional folding pattern

quaternary structure

* joining of 2 or more polypeptide chains to form one protein molecule
* 3-dimensional folding pattern with extra structures bc of the more than one polypeptide chains

Structure of Protein Molecule Determines its Function

true

Mutations

when a gene is messed up or changed

mutations potential impact on protein structure

mutations in the DNA result in mutations of the RNA which then causes mutations in the amino acid sequence which causes mutations in the protein which could possibly cause disease

mutations roll in evolution/natural selections

* mutations can cause new traits to emerge 
* This trait can be more beneficial to an environment and cause natural selection to progress

sickle cell hemoglobin

* causes red blood cells to become sickle shaped


* are weak do not hold much oxygen
* cells become hard and sticky and they die quickly causing shortage of red blood cells
* it is a genetic disorder and mutation

reduction division in chromosomes

* is another name for meiosis 


* called this as meiosis reduces the number of chromosomes there was to half

haploid chromosome number

* one copy of a chromosome like a set of chromosome from your mom
* 1

diploid chromosomes

* chromosomes from both parents giving you 46 as 23 from both parents


* 2

homologous chromosomes

* chromosomes that have the same genes so they code for the same thing but they might have different alleles so they might have different traits


* like they both code for eye color but the eye color is different

crossing over

when the traits on a chromosome cross over and exchange genetic material and the chromosomes both have traits (AKA recombinant traits)

independent assortment

* time in meiosis when the alleles assort independently so the chromatids separate to be by themselves

random fertilization

* when a random gamete meets with another 


* gametes are sex cells like sperm and egg
* when there is no physical attraction involved

zygote

a fertilized cell

genetic variation

* variation in DNA sequence in each of our genomes


* hair color, skin color, shape of our faces

Meiosis I vs Meiosis II

* I you get half as many chromosomes with their sister chromatids and then during II, you see those sister chromatids seperate into just chromatids 


* in meiosis I, you see the number of chromosomes splitting in half as you start with 6 and end with 3
* in meiosis II, you see the number of chromosomes saying the same as you start with 3 chromosomes and end with 3 chromosomes as well

Gel Electrophoresis

* take DNA and there is a positive charge on one side and negative change on another


* when the thing starts, the smaller DNA go through the holes in the gel and they go to the positive charge as DNA is negatively charged
* you can then see the large DNA vs small DNA

Restriction Enzymes

* these enzymes can recongize a specific sequence in the DNA and cut it at that specific location
* used in crisper or to clone DNA

Recombinant DNA

* DNA formed artificially by using parts form different organisms like the mouse lab we did


* we used somatic cell from one animal, egg from one animal

Karyotypes

* ways you can see all the chromosomes laid out to see any mutations like deletion, insertion, substitution


* see all 46 chromosomes 

CRISPR

* you can cut parts of your DNA and put in different ones that code for different traits 


* very controversial
* very faulty

gene pool

* collection of all alleles in a population


* more diversity = larger gene pool 

Charles Darwin

* variations in population


* competitions in populations
* certain variations are beneficial, others are not (this causes evolution)

Lamarck 

* said organisms change over time as structures used during your life time will further develop and those not used will die or be lost
* the traits that an organisms develops during their lifetime will be passed onto the next generation (is a father loses their hand, their child will be born with no hand)

Natural selection

* Survival of the fittest

More offspring than the environment can support 

the organisms that best survive to the environment will survive and reproduce

Competition

those who win and survive will reproduce

Reproductive success 

those who survive reproduction and birth will survive and reproduce (like turtles)

Genetic variation

* mutations


* gene flow 
* random mating

Small Population - Genetic Drift

* random chance on a small population


* natural disaster

Non-random mating (sexual selection)

* humans 


* how you attract to someone based on what they look like