Genetics is the branch of biology that deals with the transmission and variation of inherited characteristics.

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Why are the genomes of some trees so large?

For example, the current longest known genome belongs to a tree: http://motherboard.vice.com/read/the-largest-genome-ever-sequenced-belongs-to-a-tree I have heard that this could potentially be ...
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590 views

How do I calculate the change in allele frequency in a haploid population under selection?

From this book For simplicity, let us consider a haploid organism and assume that the frequencies of alleles $A_1$ and $A_2$ are given by $x$ and $y=1-x$, respectively. We also assume that the ...
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200 views

What is the minimum population size that Hardy-Weinberg calculations can be applied to?

I'm trying to find out if a particular allele is in Hardy-Weinberg disequilibrium, but the data is poor. What's the minimum population number that you can use to get any sort of respectable ...
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99 views

Hill-Roberston effects and effective population size

From this article, first page, middle of the second column: Even if harmful alleles do not become fixed, they can still reduce the efficacy of selection on neighbouring loci through a process ...
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608 views

Do men have a higher genetic variance than women?

I've heard that with the distribution of our genetic code women have less variation on the bell curve than men. Is there any basis for this? It was my understanding that women have more genetic ...
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332 views

Why is the strength of genetic drift inversely proportional to the population size?

I saw a concept on the Internet that says "the strength of genetic drift is inversely proportional to the population size". I don't know why they are inversely proportional? Can somebody explain? ...
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16 views

Physiological function of CFTR gene product? [duplicate]

I just need a clarification. If I am to talk about the physiological function of the CFTR gene product? Then what should I do research and talk about? The only physiological function that I can ...
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4answers
6k views

Why 22 amino acids instead of 64?

This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 22 ...
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30 views

Is this a valid definition of independent assortment?

"Allelic combinations separate randomly. I.e. a parent might be Aa and Bb for two traits but that doesn't necessarily mean the gametes will strictly be AB or ab but any of a number of combinations. ...
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90 views

What are non-heritable changes to genomes?

I am told that mutations are heritable changes to the genome. So this begs the question - what are non-heritable changes to genome?
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50 views

What impacts penetrance of Huntington's disease?

From Principles of Life by H. Craig Heller, David E. Sadava, Mary V. Price: From what I understand, Huntington's disease exhibits varying degrees of penetrance depending on how many times the ...
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1answer
88 views

XXY (Klinefelter's) & Trisomy 21 & X-inactivation

I read that X-inactivation doesn't tend to happen in males, but then when someone is XXY, they are a male because of the Y. However these individuals tend to live. So does that mean that ...
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98 views

Functions of the CFTR gene?

I am a senior in high school and I am studying cystic fibrosis. I don't quite get the function of the CFTR gene as this is my first time dealing with this type of heavy scientific info. I had ...
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64 views

How exactly can dsRNA be introduced to a cell?

Is it just by viruses or are there other means by which it gets into cells, such as plasmid uptake?
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34 views

If hermaphrodite C. elegans can reproduce with females?

C. elegans can self fertilize, or they can mate with males. But are they able to mate with females? Or is there some kind of morphological barrier that prevents that?
4
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1answer
69 views

Redundancy of the genetic code

One particular codon codes only for one amino acid, but an amino acid can be coded for by several different codons. Now according to the genetic code, the codon UUU ...
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1answer
44 views

Earliest and latest onset of Huntington's Disease(Chorea)?

Huntington's disease can hit at any age, although it tends to hit middleaged people most often. What is the youngest and oldest person that has exhibited Huntington's? Clarification: By oldest I mean ...
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1answer
44 views

DNA methylation on the forward vs reverse strand?

I'm wondering if there are meant to be differences in DNA methylation between the forward and the reverse strand of the gene? I'm wondering because in primer design for bisulfite pyrosequencing one ...
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2answers
166 views

Hardy Weinberg Equilibrium after 5 Generations

1 There is a population not at HWE where red eye = $a^+$ (dominant) and white eyes = $a^-$. if $a^+/a^+ = 0.6$ $a^-/a^+ = 0.1$ $a^-/a^- = 0.3$ what are the frequencies of the $a^+$ and $a^-$ ...
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1answer
81 views

Are all functions of a human cell known? [closed]

Please bear with me as I'm intruding into your world from a computer science background. In programming, once you have created a program, you know all functions of that program. Thus, 100% knowledge ...
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2answers
66 views

What kind of technology is required for plant seed DNA printing? [closed]

I'm a programmer so I have little knowledge in the field of biology. However I have an interest in plants, GMOs and DNA (in terms of programming). So, I want to know what kind of technology is ...
2
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2answers
68 views

How does non-homologous end joining (NHEJ) work?

I was reading about non-homologous end joining (NHEJ) in my molecular biology of the gene textbook but the explanation provided in the text was rather vague to me, and I was not able to understand it ...
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0answers
55 views

Can sealed epiphyseal growth plates theoretically be restored via epigenetic or genetic methods?

I know that epiphyseal growth plates seal up once people become young adults and that it is currently impossible to restore them to actively produce new bone growth but, is it theoretically possible ...
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657 views

Is it possible for a child to grow taller than their tallest parent?

I have heard that off spring can't grow taller than either of their parents but I've also heard that sometimes some gene activation can skip generations. Is it possible for a child to grow taller than ...
2
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1answer
128 views

What is the result of meiosis?

Is the result of meiosis ONLY the sex gametes (male and female) which later meet to form a somatic cell? Sometimes I feel as if my book is hinting towards meiosis is the process where sperm cells meet ...
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50 views

Incomplete Dominance and Probability

I have a follow-up question about an in-lecture question (this is not a homework question). As you can see I have already answered the question and the question is closed to further submissions. ...
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3answers
166 views

Why has grey hair evolved?

A vast majority of humans get at least some grey hair as they age. As far as I know this applies to both genders and all races. Presumably this means that at least some grey haired humans have ...
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1answer
60 views

Why do our epiphyseal plates close up in our late teens or early twenties?

What causes our epiphyseal plates close up in our late teens or early twenties? I realize that one's genetics plays the main role in this. I assume there is a gene that controls the epiphyseal plates ...
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64 views

Chromatids in metaphase?

Please see the following picture: In my book, the author claims that these chromosomes are in metaphase (a metaphase stopped by cholchicin). I don't understand why they don't have two ...
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72 views

At what rate do chromosomal rearrangements occur?

How often does chromosomal rearrangements occur? i.e. what is the rate of chromosomal rearrangements? I am interested about these kind of chromosomal rearrangements that are passed on to the ...
2
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1answer
46 views

How to identify genes?

You and me are different at DNA level. My eye color gene is different from yours. So, my DNA is different from yours. How can a scientist identify a certain gene in a chromosome (and its function) if ...
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60 views

How TCGA CNV values are calculated?

When I download CNV SNP array data for ovarian cancer from TCGA data portal, I see some very small numbers like -5, -6 in the "Segment_Mean" column of the segmentation data files. I am very new to ...
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1answer
91 views

What is the difference between a fixed substitution and a single nucleotide polymorphism (SNP)?

I recently read a report that stated "We found 430 fixed substitutions […], with an additional 34 single nucleotide polymorphisms (SNPs) fixed within individual patients." What is the difference ...
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5k views

Do white Australians have a distinct look?

Background I've heard from many people working in tourism or similar industries that, white Australians can be recognized as Australian solely by their facial features. Being Australian myself I've ...
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1answer
41 views

What is the difference between a DPY-10, DPY-11, and DPY-13?

My TA mentioned these three mutations of C. elegans since we started working with the worms but seems to skip over what the differences are...
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2answers
393 views

How to calculate relatedness in haplodiploid organisms (mainly full sisters and full brothers)?

I have tried to calculate the relatedness for haplodiploid organisms, but cannot understand the calculations behind full sister and full brother. (taken from Wikipedia: haplodiploidy I have managed ...
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1answer
73 views

Are there anatomical differences between male and female mammal brains before action of hormones?

is there any evidences of these differences during development stages prior to hormone driven sexual differentiation? mice studies ?
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216 views

Fisher's Geometric Model for Dummies

Fisher's geometric model is still today one of the most important and fundamental model in evolutionary biology but it seems to me that most student in evolutionary biology don't really understand it ...
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48 views

Definition of “structural underdominance”?

In Stathos and Fishman (2014), the authors refer to the concept of structural underdominance. The first time they mention it is in the first paragraph of the second page (left column) and the term is ...
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Mutation-drift equilibrium and among loci variance in heterozygosity

At mutation-drift balance, the increased heterozygosity brought by new mutations is exactly equal to the loss of heterozygosity due to genetic drift. At equilibrium, the expected heterozygosity for a ...
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19 views

Can two Hfr strains of E. coli conjugate?

Genetics textbooks (and some internet searching) yield abundant examples of Hfr strains conjugating with F- cells, but these sources are surprisingly silent regarding the results of an Hfr ...
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62 views

An unknown band appearing in my gel electrophoresis

I am having trouble understanding what is the source of band "2" in the following gel-electrophoresis: In this experiment, we took an E.coli transformant colony and ran its nucleic acids in the ...
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63 views

Why aren't introns found on the ends of pre-RNA?

We recently learned in genetics class that exons always cap the ends of nascent RNA. I have been trying to figure out the reason why introns can't instead be found on the ends instead of exons. The ...
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1answer
59 views

Influence of temperature on protein binding and decay rates

For computer modeling purposes, I am looking for some referenced quantitative measurements of the effect(s) of temperature on the dynamic of biochemical reactions. Question In particular, my ...
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1answer
69 views

What is the point of DNA sequencing?

This is a very very basic question. I've looked at methods such as chromosome sequencing and shotgun sequencing. Wikipedia says that: ...
3
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1answer
59 views

Why do we use DNA sequencing methods such as shotgun?

I am learning about DNA cloning for the first time. What I understand is that, in order to clone DNA, we break-up the original gene into shreds. Then try to piece it back together. Why exactly do we ...
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1answer
39 views

Components of the concept of Developmental Noise?

Developmental noise is a concept that correspond to the amount of possible phenotypic variance of a given genotype in a given environment. Intrinsic noise (aka Cellular noise) is a component of ...
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5k views

Does our DNA change during our lives?

As far as I know, DNA is the construction protocol of all organisms on Earth. Does it change when influenced by time and environment (physical laws)? As parents with schizophrenia are more likely to ...
4
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1answer
68 views

Influence of temperature on transcription, protein binding and decay rates

I am the kind of biologist who doesn't know much about molecular genetics and about the dynamic of biochemical reactions. Question My question concerns the influence of temperature on the dynamic of ...
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80 views

Is the mutation rate in organisms in general consistent over the genome?

Coming from computer science with an interest in genetic programming (a process emulating evolution) I'm curious about whether the rate of mutation is homogeneous across the whole genome, or if some ...