Biology Def. Unit 1

Phenotype vs. genotype

Genotype is an organism's genetic information. Phenotype is the observable trait produced by the genes and environment.  (How it relates? A bacterium's gene can give it antibiotic resistance, which is its observable resistant phenotype.)

Diversity

Individuals in a population have differences in their traits and genes. (Some bacteria are naturally resistant to antibiotics thanks others.

Allele and allele frequency

An allele is a version of a gene. Allele frequency is how common that allele is in a population. (Resistant alleles can become more common after antibiotic kill susceptible bacteria.)

Gene pool

All the genes and alleles found in a population (The bacteria population's gene pool can contain both resistance and non resistance alleles.)

Selection or natural selection

Organisms with traits that help them survive and reproduce are more likely to pass those traits on. (Antibiotics kill susceptible bacteria, while resistant bacteria survive and reproduce.)

Population bottleneck

A sudden event drastically reduces the size of a population, leaving only a small group to reproduce. (Antibiotics can greatly reduce a bacterial population. The surfing bacteria may be mostly resistant.)

Heritable traits

Traits that can be passed genetically from parents to offspring. (Antibiotic resistance can be passed from resistant bacteria to their offspring.)

Adaptation

A heritable trait that becomes common because it helps a population survive in its environment. (Antibiotic resistance is an adaption because it helps bacteria survive when antibiotics are present.)

Population vs. individual

Evolution happens to a population over generations, not to individual organisms during their lifetime. ( An individual bacterium doesn't evolve resistance because it "needs" to. Instead, resistant bacteria survive and become more common in the population."

Mutation

A change in an organism's DNA. (A mutation can sometimes give a bacterium resistance to an antibiotic.)

Lateral gene transfer

The transfer of genetic material between organisms rather than from parent to offspring. ( Bacteria can transfer antibiotic-resistance genes to other bacteria, spreading resistance quickly.)

Pathogen

A pathogen is any microorganism that is capable of causing disease in other organisms.

Antibiotics

Antibiotics are a group of drugs used to treat bacterial infections.

Bactericidal

Kills bacteria cells

bacteriostatic

slows the growth of reproduction of bacteria

Antibiotic Resistance

Genetic mutations allow bacteria to survive in presence of drugs that are designed to kill bacteria

happy distance

bond distance