A3.1: Diversity of Organisms

a group of organisms of the same species in the same area

a group of organisms that can interbreed and produce fertile offspring

The populations of two or more different species occupying the same geographical area at the same time

differences between members of a group. Variation can be discrete or continuous.

Mutation,meiosis , Gene Flow, Sexual Reproduction, Genetic Drift, Adaptive (Natural) Selection, Artificial Selection, Epigenetic Changes

traits that can be put into distinct qualitative categories.
Influced by only one or a few genes

traits that vary along a quantitative continuum. (Most types of biological variation are continuous.)
influced by multiple genes(poly genic), environment plays a significant role

--Within--
Definition: Variation within a species, often referred to as infraspecific variation, encompasses the genetic and phenotypic diversity found among individuals within a single species.

Causes: It is primarily driven by factors such as mutations, recombination, gene flow, sexual reproduction, genetic drift, and natural selection acting on the gene pool of a species.

Range: The range of variation within a species can be extensive. It includes differences in traits such as color, size, behavior, and physiology.

Importance: This level of variation is crucial for the species' adaptation and evolution. It allows a species to respond to changing environmental conditions and ensures its long-term survival.

--Between--
Definition: Variation between species, also known as interspecific variation, pertains to the differences and diversity observed when comparing different species within the same taxonomic group.

Causes: These differences are a result of accumulated changes over evolutionary time. They can include variations in anatomy, physiology, genetics, behavior, and ecological niches.

Range: The range of variation between species can be significant, leading to diverse forms of life, from microscopic bacteria to large mammals, each adapted to specific environments and ecological niches.

Importance: Interspecific variation is the basis of biological diversity and is crucial for the functioning of ecosystems. It is a product of the evolutionary process and contributes to the stability and resilience of ecosystems by creating a web of interdependencies.

Classification system in which each species is assigned a two-part scientific name

1. the genus name beings with a capital letter
2. the species name begins with a lowercase letter
3. in print, the name is in italics (underline if handwritten)
4. after one use in a text, Genus name can be abbreviated to the first letter

Reflects evolutionary relationships between organisms. All members of the same genus will share a common ancestor. Just from the name it is known that the the Pan paniscus and Pan troglodytes are more closely related to each other than either is to the Gorilla gorilla.

Enables scientists to talk to each other in the same language. The same species can have many different local names so binomial nomenclature allows for consistency in communication around the world.

Species are groups of animals that are categorized by their physical characteristics

a group of organisms that are able to interbreed and produce fertile offspring.

Hybrids - in the wild, they are infertile, but in captivity they can be fertile
asexual species - species that don't interbreed but when a single parent passes a complete set of genes to offspring, creating a genetically identical offspring
limited technology and ethics when observing natural breeding and production of fertile offspring
chronospeices that share the same lineage but are in different stages of evolution(unable to know if instinct animals were fertile or how they reproduced)

the formation of new and distinct species in the course of evolution.

Gradual Change: The process of speciation often occurs gradually, with small changes accumulating over time. There is no clear point where one population becomes a distinct species, making it hard to pinpoint when speciation has occurred.

Intermediates: During speciation, there can be intermediate populations that share characteristics of both the original and the emerging species. This blurs the lines between what is considered a separate species.

Hybridization: Hybridization between populations or species can occur, creating fertile offspring that share genetic material from both parent groups. This makes it difficult to classify these hybrid populations as either one species or another.

Geographic Isolation: If populations are geographically isolated, it can be challenging to assess their genetic compatibility and potential for interbreeding, especially if they are not in direct contact.

Lack of Clear Criteria: There is no universally agreed-upon set of criteria that definitively define when one population has become a new species. Different species concepts (e.g., biological, morphological, ecological) may yield different results in different scenarios.

These difficulties illustrate the complexity of the speciation process and the challenge of distinguishing populations and species, especially when considering the various factors that come into play during evolution.

a visual arrangement of The full set of chromosomes in an organism's cells. that is by organzied by size, shape and branding patterns

a specfic photograph of a karyotype with chromosomes orgized in a systematic order for detailed examination, used to analysis genetic information and chromosomal abornmalities

Size: Chromosomes are typically arranged in order of size, from the largest to the smallest.

Shape: The shape of chromosomes, which can vary from metacentric (V-shaped) to telocentric (rod-shaped), is considered when arranging them.

Band Patterns: Chromosomes are often grouped based on their banding patterns, which are created by staining techniques, revealing unique patterns of dark and light bands on the chromosomes.

Centromere Position: The position of the centromere, which divides chromosomes into short and long arms, is used to further distinguish and arrange them.

These characteristics help create a standardized and organized representation of an individual's chromosome set for analysis and diagnosis.

The complete set of an organism genetic code(including DNA sequences and genetic information) contains instructions for developement, function and reproduction of the organsism

a segement of DNA that codes for a specfic protein or performing a specfic function. They are basic units of hereditary and have a crucial role in determing an organism's traits

variant or alternate form of a gene occupies a specific location (locus) on a chromosome. They can differ from one another in terms of what DNA sequence they have and can result in various traits within an individual. It can be dominant or recessive

a single nucleotide is replaced with another

--Cause--
Mutations: Random changes in DNA sequences that can occur during DNA replication, environmental exposure, or other factors. Mutations can lead to the creation of new SNPs.

Genetic Diversity: Over time, populations accumulate genetic diversity through mutations and genetic recombination. Some of these variations become common SNPs within a population.

--Effect--
Trait Variation: SNPs can contribute to individual differences in physical traits, such as eye color, hair color, and height. They can also affect susceptibility to specific genetic diseases.

Pharmacogenetics: SNPs can influence an individual's response to drugs. Variations in drug metabolism-related SNPs can impact how effective a medication is or whether it may cause adverse reactions.

Disease Susceptibility: Certain SNPs are associated with an increased risk of developing specific diseases, such as heart disease, cancer, or diabetes. These genetic variants can provide insights into an individual's genetic predisposition to particular health conditions.

Population Genetics: SNPs are used in population genetics studies to trace human migrations and evolutionary history. Patterns of SNP variation can help researchers understand the genetic diversity and relatedness of different populations

Gene duplication can occur within a genome wich lead to multiple copies of the same gene. These gene duplicates are considered to be apart of the same gene family and thus they only represent a single functional gene not multiple

Non coding DNA - Most genomes consits of non coding DNA, non coding DNA includes regulatory sequences, repetitive elements and regions that don't code for protein these parts play an important role in genome stability and gene regulation it does not contribute to the amount of genes in an organisms

Gene size: Genomes can be big and code for complex proteins while others can be small. The amount is determined by the agreement and size of the coding regions

Base pairs(BP
kilobase pairs(Kbp or Kb)
megabase pairs(Mb or Mbp)
gigabase pairs(Gbp or Gb)

Sequence is the specific order of nucleotides(Cytsosine, Adenine, guanine, thymine) in DNA molecule, this has the genetic information for coding for protein, regultion of gene expression and the functioning of the organism. Sequences can vary in genes in an individual and species, they also play a crucial role in genetics and genomics research

Disease Diagnosis: Identifying genetic mutations and variations associated with diseases, allowing for earlier diagnosis and personalized treatment.

Pharmacogenomics: Tailoring drug treatments to an individual's genetic profile for more effective and safer medication.

Agriculture: Improving crop yields and disease resistance in agriculture through genomics-assisted breeding.

Forensic Science: Solving crimes by analyzing DNA evidence and identifying individuals through DNA profiling.

mutation - changes in sequences in DNA
Gene flow - the movement of genes between different populations of organisms
Meiosis - formation of egg and sperm which leads to new combinations of alleles
Sexual reproduction - fertilization between egg and sperm

two complete sets of chromosomes(1 from paternal and 1 from maternal) in an organism's cells

organized into pairs.
Each pair consists of one chromosome from the mother and one from the father.
homologous pairing, ensures that the genetic material is distributed evenly during cell division.
allows for a more balanced and accurate distribution of genetic information, which is crucial for the proper functioning and development of an organism.

the process of determining the order of the bases in an organism’s genetic code

The genes of chromosome 2 closely match those of the two suspected fusion chromosomes in chimpanzees
Telomeric DNA (repetitive sequences found at the end of chromosomes) were found at the fusion region of chromosome 2
The second centromere region (where the cytoskeleton attaches to the chromosome) but this one has mutated and is non-functional
Branding pattern on 12 matches with branding pattern 13
explaints why humans have 46 chromosomes while apes have 48
gene order matches 12 + 13
strong eviedence/widley accepted by based on interference from current genes

Autosome: any chromosome that is not a sex chromosome

Sex chromosome: type of chromosome responsible for the chromosomal determination of the sex of an individual

If the karyogram shows two X chromosomes (XX), the individual is female.

If the karyogram shows one X and one Y chromosome (XY), the individual is male.

refers to the specific order of nucleotides (adenine, thymine, cytosine, and guanine, represented by the letters A, T, C, and G) in a DNA or RNA molecule. This sequence provides the genetic information necessary for the formation of proteins, regulation of gene expression, and the functioning of an organism. Sequences can vary between genes and among different individuals and species, and they play a crucial role in genetics and genomics research.

Benefits: disease diagnosis, personalized treatment, ancestry studies, agricultural improvements.
Concerns: privacy of genetic data, potential discrimination (insurance/employment), informed consent, ownership of genetic information, designer babies.