Population genetics is the field of biology that studies allele frequencies in populations and how they change over time.Two fundamental calculations are central to population genetics: allele frequencies and genotype frequencies
hardy weinberg genetic equilibrium by kk sahuKAUSHAL SAHU
INTRODUCTION
HISTORY
THE HARDY-WEINBERG LAW
DERIVATION
TERMINOLOGY
PROBLEMS
ASSUMPTION OF HAEDY –WEINBERG EQUILIBRIUM
REFERANCE
The Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem or law.
States that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.
These influences include mate choice, mutation, selection, genetic drift, gene flow and meiotic drive.
Because one or more of these influences are typically present in real populations, the Hardy–Weinberg principle describes an ideal condition against which the effects of these influences can be analyzed.
hardy weinberg genetic equilibrium by kk sahuKAUSHAL SAHU
INTRODUCTION
HISTORY
THE HARDY-WEINBERG LAW
DERIVATION
TERMINOLOGY
PROBLEMS
ASSUMPTION OF HAEDY –WEINBERG EQUILIBRIUM
REFERANCE
The Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem or law.
States that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.
These influences include mate choice, mutation, selection, genetic drift, gene flow and meiotic drive.
Because one or more of these influences are typically present in real populations, the Hardy–Weinberg principle describes an ideal condition against which the effects of these influences can be analyzed.
Population Genetics & Hardy - Weinberg Principle.pdfSuraj Singh
This presentation is all about the population genetics.
In this presentation I would like to explain about the population genetics, calculation of allele frequencies, calculation of frequencies of sex - linked alleles.
Also there is a detailed explanation of Hardey-Weinberg equilibrium or principle.
In the last there are few key points regarding with the assumptions and steps for the Hardy-Weinberg principle.
Hardy Weinberg law
Hardy Weinberg Equilibrium with Solved Questions|CSIR NET|Life Sciences|GATE|JRF|ICMR|
Video link: https://youtu.be/CUKGoxpptM8
Hardy Weinberg Law along with the assumptions the law is based on. Calculation of allelic and genotypic frequencies. Application of Hardy Weinberg law to different cases viz Multiple alleles, Polyploidy, Inbreeding and X-linked + Questions are discussed.
Population Genetics & Hardy - Weinberg Principle.pdfSuraj Singh
This presentation is all about the population genetics.
In this presentation I would like to explain about the population genetics, calculation of allele frequencies, calculation of frequencies of sex - linked alleles.
Also there is a detailed explanation of Hardey-Weinberg equilibrium or principle.
In the last there are few key points regarding with the assumptions and steps for the Hardy-Weinberg principle.
Hardy Weinberg law
Hardy Weinberg Equilibrium with Solved Questions|CSIR NET|Life Sciences|GATE|JRF|ICMR|
Video link: https://youtu.be/CUKGoxpptM8
Hardy Weinberg Law along with the assumptions the law is based on. Calculation of allelic and genotypic frequencies. Application of Hardy Weinberg law to different cases viz Multiple alleles, Polyploidy, Inbreeding and X-linked + Questions are discussed.
This presentation covers the basic terminology and key parameters of Population Genetics. Presentation is helpful for the students of Life Sciences and Evolutionary biology.
Cross- pollinated crops are highly heterozygous due to the free intermating among their plants. They are often referred to as random mating populations because each individual of the population has equal opportunity of mating with any other individual of that population. Such a population is also known as Mendelian population or panmictic population. A population, in this case, consists of all such individuals that share the same gene pool, i.e., have an opportunity to intermate with each other and contribute to the next generation of the population. To understand the genetic make - up of such populations a sophisticated field of study, population genetics, has been developed. The Hardy Weinberg law states that in a large random mating population gene and genotype frequency remain constant generation after generation unless there is selection, mutation, migration or random drift. This is the fundamental law of population genetics and provides the basis for studying Mendelian populations. The law is proposed independently by G. H. Hardy (a mathematician) and W. Weinberg (a physician).
Foundations of Biological Sciences I Evolutionary Agents - 1 .docxbudbarber38650
Foundations of Biological Sciences I Evolutionary Agents - 1
A quick recap….
There are several terms that need to be clarified so that you can more easily follow the exercise. A gene is a
piece of DNA that directs the expression of a particular characteristic (trait). Genes are located on
chromosomes, and the location where a particular gene is found is referred to as the locus (plural: loci) of that
gene. An allele is a gene for which there is an alternative expression, which can lead to the alterative form of a
trait. For example, a diploid organism carries the allele “A” on one homologous chromosome, and the allele “A”
on the other. The genotype of this organism is then AA and it is said to be homozygous. An organism may also
carry two different alleles. For example on one chromosome it could carry the allele “A” and on the other it
could carry the allele “a”. The genotype of such an organisms is then Aa, and it is described as heterozygous for
this chromosomal locus.
The genotype of an organism is the listing of the two alleles for each trait that it possesses. The phenotype of an
organism is a description of the way a trait is displayed in the structure, behavior, or physiology of the organism.
Some alleles are dominant to others and mask the presence of other alleles. The dominant condition is indicated
by uppercase letters (e.g., “A”). The alleles that are masked are called recessive alleles. The recessive condition
is indicated by lowercase letters (e.g., “a”). When both dominants are present in the genotype (AA), the organism
is said to be homozygous dominant for the trait, and the organisms will show the dominant phenotype (trait
expression A). When both recessives are present in the genotype (aa), the organism is said to be homozygous
recessive for the trait, and the organisms will show the recessive phenotype (trait expression a). In the case of
complete dominance, the dominant allele completely masks the recessive allele, and an organism with a
heterozygous genotype (Aa) will show the dominant phenotype (trait expression A).
Evolutionary Agents
Evolution is a process resulting in changes in gene frequencies (= the genetic make-up) of a population over
time. The mechanisms of evolution include selection (which can cause change over time & adaptation), and
forces that provide variation and cause change over time (but not adaptation). Factors that change gene
frequencies over time are referred to as evolutionary agents.
A powerful way to detect the presence of evolutionary agents is the use of the Hardy–Weinberg model. This
model can be applied to traits that are influenced by several loci; the simplest case is for a trait that is regulated
by one locus with two alleles.
With the Hardy–Weinberg model, the frequency of genotypes in the population can be predicted from the
probability of encounters between gametes bearing the different alleles. With alleles R .
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
2. Introduction
• Population genetics is the field of biology that studies allele frequencies in populations
and how they change over time.
• Genetic variation in populations can be analyzed and quantified by the frequency
of alleles.
• Two fundamental calculations are central to population genetics: allele frequencies and
genotype frequencies.
• Population genetics examines genetic variation within and between populations, and
changes in allele frequencies across generations.
• Population geneticists use mathematical models to investigate and predict allele
frequencies in populations.
Swathi Sasidharan ,Bsc.Biotechnology
3. • Allele, also called allelomorph, any one of two or more genes that may occur alternatively at a
given site (locus) on a chromosome.
• Alleles may occur in pairs, or there may be multiple alleles affecting the expression (phenotype)
of a particular trait.
• The combination of alleles that an organism carries constitutes its genotype.
• If the paired alleles are the same, the organism’s genotype is said to be homozygous for that
trait;
• if they are different, the organism’s genotype is heterozygous.
Allele
Swathi Sasidharan ,Bsc.Biotechnology
4.
5. • Allele frequencies can be represented as a decimal, a percentage, or a fraction.
• Allele frequency refers to how common an allele is in a population. It is determined by
counting how many times the allele appears in the population then dividing by the total
number of copies of the gene.
• Frequency of allele A= Number of copies of given Allele in population.
Sum of counts of all alleles in the population
• In a population, allele frequencies are a reflection of genetic diversity. Changes in
allele frequencies over time can indicate that genetic drift is occurring or that new
mutations have been introduced into the population.
Allelic Frequency
Swathi Sasidharan ,Bsc.Biotechnology
6. EXAMPLE
• Consider a population with a certain count of AA, Aa ,aa containing diploid
individuals.
• When two alleles are present at a locus ,we can use the following formula to
calculate the allele frequencies :-
p = f(A) = (2 x count of AA) + (count of Aa)
2 x total number of individuals.
Swathi Sasidharan ,Bsc.Biotechnology
7. Allele Frequencies with Multiple Alleles
Consider three alleles A1,A2 and A3 at a locus ,
To determine allelic frequencies,use the same rule that used with two alleles, add up the
number of alleles of each type and divide by the total number of alleles in the population.
P = f(A1) = (2 x count of A1A1)+ (A1A2) +(A1A3)
(2 x total number of indivduals)
P = f(A2) = (2 x count of A2A2)+ (A1A2) +(A2A3)
(2 x total number of indivduals)
P = f(A3) = (2 x count of A3A3)+ (A1A3) +(A2A3)
(2 x total number of indivduals)
Swathi Sasidharan ,Bsc.Biotechnology
8. • Genotype frequency in a population is the number of individuals with a
given genotype divided by the total number of individuals in the
population.
• In population genetics, the genotype frequency is the frequency or
proportion (i.e., 0 < f < 1) of genotypes in a population.
• Although allele and genotype frequencies are related, it is important to
clearly distinguish them.
• Genotype frequency may also be used in the future (for "genomic
profiling") to predict someone's having a disease or even a birth defect.
• It can also be used to determine ethnic diversity.
Genotypic Frequency
Swathi Sasidharan ,Bsc.Biotechnology
9. EXAMPLE:-
• Consider a locus that determines the pattern of spots in scarlet tiger moth,Panaxia dominula.
Three genotypes are present in most populations and each genotype produces a different
phenotype .
• E.B Ford collected moths at one locality in England and found the following numbers of
genotypes: 452 BB, 43 Bb,2bb for a total of 497 moths.
• So the genotypic frequencies are therefore
f(BB) =452/497 =0.909
f(Bb) = 43/497 = 0.087
f(bb) = 2/497 = 0.004 where f = frequency.
Swathi Sasidharan ,Bsc.Biotechnology
