Unit 1 - Genetics Flashcards
What are the 8 characteristics of life?
- living organisms are made up of self sustaining units (cells)
- living organisms can reproduce (reproduction)
- all living organisms on earth use nucleic acids (RNA and DNA) as an info molecule
- living organisms grow and develop over the course of their lives
- living organisms needs a constant input of energy, and unhindered ability to exchange matter with their environment
- living organisms are able to detect changes in their environment and respond to those changes
- living organisms maintain a stable internal environment (homeostasis)
- living organisms (populations) evolve over time (evolution)
What is the difference between dead and never living?
Non-living things lack the characteristics of life while dead things did have characteristics of life when they where alive.
What is the definition of evolution?
Evolution is the change in inherited characteristics in a population over generations.
Understand the “driver” of evolution and the 4-step process of evolution.
- The potential for populations to increase in numbers (overproduction)
- Genetic variation as a result of mutation and sexual reproduction (variation)
- Competition for resources (natural selection)
- Proliferation of individuals with better survival and reproduction (inherited)
Know what adaptations are and how they relate to evolution.
An adaptation is any heritable trait that suits an organism to its natural functional role in the environment.
Adaptations are a product of natural selection and can be structural (morphological), physiological, or behavioral traits. Traits that are not helpful to survival and reproduction will not be favored and will be lost.
Adaptation is important in an evolutionary sense because adaptive features promote fitness. Fitness is a measure of an organism’s reproductive success (genetic contribution to the next generation).
Know what mutations are and how they relate to evolution.
Mutations are changes to the DNA sequence and occurs throughout errors in DNA copying. Changes to the DNA modifies existing genes and can create variation in the form of new alleles. Ultimately, mutations are the source of all new genetic variation.
Mutations within an organism can evolve over time allowing for that organism to adapt to its environment better. Examples include rats becoming tolerant to poisons and etc.
Why is variation important? How does variation come about (know three ways)?
Variation in population or species is important in changing environment. Both sexually and asexually reproducing species have strategies to increase variation.
Variation may come from changes to the genetic material (mutation), through sexual reproduction, and as a result of the effects of the environment.
How was Darwin’s theory of Natural Selection misused in the 1800s (and into early 1900!)?
Darwin’s theory of Natural Selection was misused in the 1800s and early 1900s because it started up the eugenics movement in which people believe due to Darwin’s research that race was biological so they wanted to erase races and try to make the populations more “pure”.
What is a common misconception about race and biology? What do you now know is true about race and biology?
A misconception about race and biology is that humans can be separated biological by race. In reality humans are not divisible into biological races because their isn’t enough genetic diversity and differences to point to that conclusion.
Understand how the terms DNA, chromosomes, and genes are related.
DNA is the carrier of genetic information present in nearly all living organisms.
Chromosomes are a single long molecule of DNA coiled around his tone proteins. Chromosomes contain protein-coding regions called genes.
Genes are a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
Be able to identify and apply the following genetics terms: alleles, homozygous, heterozygous, dominant and recessive, homologous pairs, genotype, and phenotype.
Alleles: one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.
Homozygous: When both the alleles are the same (example: DD and dd)
Heterozygous: When each allele is a different variation of a gene (example: Dd)
Dominant: Variation of the gene most likely to show up (example: DD or add)
Recessive: Variation less likely to show up (only shows up with homozygous recessive (dd))
Homologous pairs: A pair of chromosomes, which one is from each parent.
Genotype: The genes for an individual trait (example: DD, Dd, dd)
Phenotype: The physical look of an individual and the trait (example: Dark coat or light coat)
Be able to do monohybrid cross and dihybrid cross problems to determine genotypic and phenotypic ratios of offspring.
Textbook sections 208, 209, and 210
What is the difference between a characteristic and a trait? Be able to give an example/ identify.
A trait is a version of a character.
A characteristic is a recognizable feature controlled by genetics.
Example: Rabbits
Characteristics: fur color or shape
Traits: white fur or wrinkled
Understand what parent generations, F1 generations, and F2 generations refer to
Parent generations refer to starting generation.
F1 generations refer to the offspring/ population of the parent generations.
F2 generations refer to the offspring/population of the F1 generation.
What does codominance mean? Be able to give/ identify an example.
Codominance refers to a type of inheritance in which two versions (alleles) of the same gene are expressed separately to yield different traits in an individual.
An example would be a chicken where the mother is white and the father is black but the offspring is black and white checkered.
