Biology Comprehensive Review

Primary protein structure

a sequence of a chain of amino acids is put together in rows at the ribosomes.

Secondary protein structure

hydrogen bonds give structure by causing the amino acids to fold in a repeating pattern.

Tertiary protein structure

side chain interactions cause the protein to fold in a three-dimensional pattern.

Quaternary protein structure

two chains of amino acids combine to make one protein.

Enzymes

proteins that catalyze biochemical reactions.

Antibodies

proteins produced by the immune system to help remove foreign substances and fight infections.

DNA-associated proteins

regulate chromosome structure during cell division and/or play a role in regulating gene expression, for example, histones and cohesin proteins

Contractile proteins

involved in muscle contraction and movement, for example, actin and myosin

Structural proteins

provide support in our bodies, for example, the proteins in our connective tissues, such as collagen and elastin.

Hormone proteins

coordinate bodily functions, for example, insulin controls our blood sugar concentration by regulating the uptake of glucose into cells.

Transport proteins

move molecules around our bodies, for example, hemoglobin transports oxygen through the blood.

Motor proteins

bend and swing to literally walk across the cell's cytoskeleton

Motor proteins

bend and swing to literally walk across the cell's cytoskeleton

Acetylcholine

a neurotransmitter that opens a hole in the center of a membrane to allow the diffusion of sodium ions, which starts a nerve signal.

Carbohydrates

macromolecules used for energy and structure in the cell.

Lipids

macromolecules used to store energy and for structure in the cell.

Proteins

macromolecules that generally do the work of the cell and transport other molecules.

Nucleic acids

macromolecules used for heredity and cell instruction.

DNA

the genetic information of the cell.

RNA

a nucleic acid that carries a portion of genetic code from the nucleus to the ribosome in order to create one protein.

Chromosomes

an organized, condensed segment of genetic instructions.

Chromatid

a strand of a replicated chromosome.

Centromere

part of the chromosome where sister chromatids are held together.

Amino acid

the subunit of proteins.

Nucleotide

the subunit of DNA and RNA.

Genes

most basic unit of heredity that contains genetic information.

Gametes

sex cells; egg and sperm that contain only one copy of each chromosome.

Somatic cells

all cells in the body besides gametes.

Homologous chromosomes

chromosomes that are the same size and contain the same types of genes in the same locations.

Karyotype

Sexual reproduction

two cells from different parents combine to form one cell, the offspring.

Cell cycle

a cycle of steps during which a cell grows and divides.

Cell division

the process in which one cell divides and produces one or more daughter cells.

Daughter cells

new identical cells created through cell division.

Transcription factors

proteins that bind to DNA and replicate the genetic code.

Spindle apparatus

protein fibers that pull apart and move chromosomes.

Recombinant chromosomes

offspring chromosomes with genetic variation from parent chromosomes due to recombination of DNA sequences.

Stop codons

signal DNA stopping for mRNA during translation.

Start codon

the amino acid methionine that signals the beginning and initiation of translation.

Transcription

the process of making RNA from DNA bases.

Translation

the process of using RNA to make a protein.

Replication

the process of making a copy of DNA.

Helicase

an enzyme that unzips the DNA molecule, preparing it for replication.

Primase

an enzyme that adds a few RNA bases to make a primer.

DNA polymerase

an enzyme that adds the corresponding DNA bases to create the complementary strand of DNA.

RNA polymerase

the enzyme responsible for copying DNA sequence into an RNA sequence during transcription.

Exonuclease

an enzyme that removes the primer from the DNA strand.

DNA ligase

an enzyme that seals the fragments of DNA strands.

Meiosis

the production and division of gametes, produces 4 genetically unique cells with only 1 set of chromosomes, with 23 chromosomes per cell.

Mitosis

cell division of the nucleus of somatic cells, produces 2 identical cells with 2 sets of chromosomes, with 46 chromosomes per cell.

Gene

a portion of DNA that codes.

Allele

a variation of a gene copy.

Phenotype

physical traits.

Genotype

genetic traits.

Dominate genes

an allele that is expressed with one of two copies.

Recessive

an allele that is hidden by the dominate gene copy; must have two copies to be expressed.

Punnett Square

a chart used to predict the genotype of an offspring based on the genotype of their parents.

Homozygous

a genotype with two of the same alleles.

Homozygous dominant

a genotype with two dominant alleles.

Homozygous recessive

a genotype with two recessive alleles.

Heterozygous

a genotype with one dominant allele and one recessive allele; those with this genotype are also known as a carrier for the recessive trait.

Carrier

an individual that carries a recessive trait that is not expressed but can be passed on to offspring.

X-linked traits

traits carried only by the X chromosome.

Epigenetics

the environmental influence on gene expression.

Germ theory

the theory that microscopic organisms cause illnesses.

Pathogen

the disease-causing agent (eg. virus or bacteria).

Antigen

a protein on the surface of the cell which serve as an ID tag.

Antibody

proteins released by an immune cell that surrounds a pathogen.

Antigen receptor

a protein on the surface of immune cells which identify antigens as “non-self” and as a specific pathogen.

B-cell

an immune cell which has antigens, can produce antibodies, or become memory cells.

Macrophage

an immune cell that surrounds and destroys a pathogen.

Memory cells

cells of the immune system that stay in the body carrying that precise antigen.

Antibodies

proteins released by a B-cell and target invaders.

Vaccine

an inactive, weak, mutated, dead, or synthetic pathogen introduced to the immune system to prompt the production of B-cells and memory cells.

Herd immunity

the concept that the more people who are vaccinated, the more the population is protected from the spread of a disease.

Population

individuals of the same species in the same area at the same time.

Genetics

the study of biological inheritance.

Inheritance

the passing of traits or characteristics from parent to offspring.

Population genetics

inheritance patterns among a group.

Evolution

any change in heritable genetics within a population across generations, over time.

Genetic diversity

the differences in alleles found within a population.

Gene flow

the exchange of alleles among two or more populations, ie through migration.

Adaptations

mutations or new traits that benefit the survival of an individual.

Recombination

the random mixing of DNA among two organisms.

Mutation

a random change in DNA.

Competition

interaction between organisms or species in which both require a resources that is limited in supply.

Niche

the functional role of an organism in its habitat.

Bottleneck effect

a random, natural even that significantly reduces a population and decreases genetic variation.

Founder effect

the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population.

Genetic drift

the change in the frequency of existing genetic variation in a population due to random chance; or evolution caused by random chance factors.

Carrying capacity

the maximum population size which can be sustained in a particular environment.

Greenhouse effect

the naturally occurring phenomenon in which molecules in the atmosphere naturally trap some of the Sun's energy as heat.

Describe how diffusion works.

substances move across an area of high concentration to an area of low concentration until equilibrium is met.

Describe why ribosomes are essential for life.

ribosomes synthesize proteins which do all the work of the cell.

Describe how vaccines work.

weak, mutated, inactive, or synthetic pathogens are introduced to the immune system, which creates matching B-cells to the pathogen’s specific antigen so it can fight it off better if reinfected.

Describe what happens to proteins in environments that are too high or low in pH or temperature.

proteins lose their shape and therefore their function, resulting in denaturation.

Cell/plasma membrane

semi-permeable wall that regulates the passage of some substances such as molecules, ions, and water. Helps maintain homeostasis.

Cytoplasm

a gel-like fluid inside the cell that suspends organelles where many reactions take place.

Cytoskeleton

a network of protein fibers that maintain the shape of the cell and stabilize the organelles. Composed of three types of proteins; actin fibers, microtubules, and intermediate fibers.

Ribosome

site of protein synthesis.