Active Transport, DNA Structure, Sodium-Potassium Pump, Protein Synthesis, Mutations, Gene Expression, Digestion

Active Transport

Movement of molecules against concentration gradient

Requirements of Active Transport

Input of extra energy, occurs across cell membrane, requires carrier proteins

Active Transport of Macromolecules

Transport of large molecules through endocytosis and exocytosis

Endocytosis

Cell membrane takes in macromolecules by forming vesicles

Exocytosis

Internal vesicles containing macromolecules fuse with cell membrane

Sodium-potassium pump

Protein in cell membrane that moves sodium and potassium ions

Purpose of the sodium-potassium pump

Maintain resting potential and establish electrochemical gradient

Structure of DNA

Double helix formed by two polynucleotide strands

Gene

Section of DNA that codes for a protein

DNA Replication

Process of synthesizing new DNA strands

Helicase

Enzyme that unzips DNA strands

Topoisomerase

Enzyme that relaxes supercoiled DNA

Primase

Enzyme that creates starting point for DNA polymerase

DNA polymerase

Enzyme that adds DNA nucleotides to build new strands

Exonuclease

Enzyme that removes RNA primers and fixes DNA

Ligase

Enzyme that glues DNA fragments together

Proofreading

Process where DNA polymerase fixes errors

Leading strand

DNA strand built in the 5 to 3 direction

Lagging strand

DNA strand built in the 3 to 5 direction

Unzipping

Helicase breaks hydrogen bonds between DNA strands

Stabilizing

Single stranded binding proteins prevent DNA from joining back together

Priming

Primase attaches RNA primers to DNA

Replacing

Exonuclease removes RNA primers and DNA polymerase replaces with DNA nucleotides

Gluing

Ligase joins DNA fragments together

Protein Synthesis

Process of building proteins from amino acids

Eukaryotic cells

Contain nucleus, ribosomes, and cytoplasm

Transcription

DNA is transcribed into mRNA

Translation

mRNA is translated into a protein

DNA code

Genetic code that determines characteristics

Gene Expression

Using a gene to make a protein

Transcription factors

Regulatory proteins that increase or decrease transcription

Positive transcription factors

Activators that help RNA polymerase bind and begin transcription

Negative transcription factors

Repressors that block or make transcription more difficult

siRNA and miRNA

Short pieces of RNA that interfere with gene expression

Histones

Proteins that condense DNA

Epigenetic markers

Heritable changes that affect phenotype without changing DNA sequence

Digestion

Process of breaking down food and absorbing nutrients

Alimentary Canal

Digestive tube with serosa, muscularis, submucosa, and mucosa

Teeth

Accessory organs for mechanical digestion

Salivary glands

Produce saliva for chemical digestion

Bolus

Food mass that moves down the esophagus

Stomach

Organ for chemical and mechanical digestion

Chyme

Gastric juice in the stomach

Small intestine

Location of most digestion and nutrient absorption

Villi

Finger-like projections in small intestine for nutrient absorption

Peristalsis

Involuntary muscle contractions that move food through the digestive system

Large intestine

Absorbs water and eliminates waste

Rectum

Stores undigested waste before elimination

Haustra

Pouches in the large intestine

Gene Mutation

Change in an organism's genetic material

Mutagens

Factors that increase the risk of mutation

Substitution

Mutation where one base is exchanged for another

Insertion

Mutation where one or more bases are added

Deletion

Mutation where one or more bases are removed

Silent mutation

Mutation with no effect on amino acids

Missense mutation

Mutation that changes the amino acid

Frameshift mutation

Mutation that changes the reading frame of codons

Nonsense mutation

Mutation that creates a stop codon

Chromosomal mutations

Mutations that affect whole chromosomes

Aneuploidy

Organism has too many or too few chromosomes

Polyploidy

Organism has multiple sets of chromosomes

Epiglottis

Flap that blocks the larynx during swallowing