AN101 what i dont know

haploid is a product of

meiosis

• a cell with 1 set of chromosomes 

meiosis

is for gametes

• 4 unique gametes

1 diploid = 2 sets of chromosomes

crosses over

then gets rearranged through independent assortments

pulled into 4 haploids

mitosis

is for other cells

• diploid cell divides and makes 2 identical duaghter cells

cell division 

1 single diploid that divides by having the copies pull apart 

explain protein transcription

1st step to protein synthesis
enzyme unzips DNA sequence
makes copy puts into mRNA

• switches all T with U

explain protein translation

2nd step to protein synthesis

mRNA goes to ribosome to tRNA

tRNA matches up with mRNA’s codons

amino acids link together to make polypeptide that fold into finished protein

what are mendel’s rules

1. segregation

2. dominance

3. independent assortment

segregation

• Each individual has 2 alleles for a trait 

• These alleles separate during meiosis

  • Ex: Pp plant produces gametes with either P or p 

dominance

• Dominant allele will overpower recessive 

independent assortment 

• Genes for different traits are passed to gametes independently of one another

  • Example: Seed color and seed shape are inherited independently, so you can get yellow-round, yellow-wrinkled, green-round, and green-wrinkled seeds.

polygenic traits

influences by 2 or more genes
- complex 

pleiotropy 

occurs when a single gene influences multiple, often unrelated, phenotypic traits.
- foxes 

• ex: selection for the single trait of docility (tameness) in foxes also led to unintended changes in coat color and ear shape

directional selection

favors one extreme phenotype

• Example: Selection for higher hemoglobin concentration in high-altitude Andean populations to improve oxygen transport.

stabilizing selection

favors intermediate phenotype

• Example: Human birth weight, where both very small and very large babies have lower survival rates than average-sized babies.

disruptive selection

Favors both extreme phenotypes over the intermediate one. This can lead to the population splitting into two distinct groups.

Biological Species Concept (BSC)

Defines a species as a group of populations that can interbreed and are reproductively isolated from other such groups.

Ecological Species Concept (ESC) 

Defines a species by its unique ecological niche, emphasizing the role of natural selection in maintaining species boundaries.

 Recognition Species Concept (RSC)

Defines a species by a shared, unique mate-recognition system.

Evolutionary Species Concept

Defines a species as a single lineage of ancestor-descendant populations with its own unique evolutionary trajectory.

gradualism 

slow steady change of time for evolution 

punctuated

in steps, a concept associated with Stephen Jay Gould, proposes that species often remain relatively static for long periods, with rapid evolutionary change and speciation occurring in short bursts, often triggered by environmental changes.

adaptive radiation 

is the rapid expansion and diversification of species into new ecological niches.

ecological niche 

is the specific position a species occupies within its environment, including its diet, habitat, and interactions with other species. 

adaptive radiation can happen 

   1. Extinction of competitors, which opens up niches (e.g., the flourishing of mammals after the extinction of dinosaurs).

    2. Colonization of a new area where there are no competitors (e.g., the ancestor of all lemurs arriving in Madagascar).

    3. The evolution of an "adaptive breakthrough," a key new trait that allows a group to exploit new environments (e.g., the amniotic egg in reptiles, which allowed them to colonize land).

Systematics

he broader field that combines both taxonomy and phylogenetic reconstruction to create a classification system that reflects evolutionary history.

Taxonomy

theory and practice of naming and classifying organisms into a coherent framework. Modern taxonomy was founded by Carolus Linnaeus, who developed the hierarchical system (Kingdom, Phylum, Class, etc.) and binomal nomenclature we use today 

Phylogenetic

 determining the evolutionary relationships between organisms.