Showing posts with label Genetics. Show all posts
Showing posts with label Genetics. Show all posts

Interpretation of the results of Mendel's experiments in Flower color inheritance in pea plant

Interpretation of the results of Mendel's experiments in Flower color inheritance in pea plant:

  • Mendel assumed that there is a reason to make the color red flower and another reason to make the color white flower and named each cause hereditary factor
  • these factors are transmitted through gametes note and feminine
  • Each recipe has alleles govern Zarōha If similarity Alolelan was pure character and If Alolelan differ character is pure
  • eparated Alolelan apart when gametogenesis so that each gamete carries one allele for each recipe.

Mendel's first law:

"Every recipe has a genetic ALIL Anazlan apart when gametogenesis"
Ills - recessive character always pure?
Because one allele enough cushions for the emergence of such prevailing.

Probability and genetics:

When you throw AED, the likelihood of the emergence of the face that holds writing ½ or 50%, as well as the face that bears the image
If the throw caps at the prospect of the emergence of duplex type = ¼ or 25%
These laws apply to genetics completely
"Hereditary issues Page 133 Student's Book".

Rules possibilities:

  • reflects the possibilities fracture or a percentage ranging from zero to one true (100%)
  • the possibility of two independent events together is the result of hitting prospect each of them separately.

Mendelian traits in genetics.. Qualities that are subject to the rule is fully in human

Mendelian traits in genetics

Full sovereignty is: 

And does not prevail any of the other alleles fully sovereign, but appear together recipe centrist In this case reflects each allele with a different code. 

How do we know that the issue of the rule is complete?

 If per character has three aspects for example, be a recipe color (red - white - pink) as in the plant palate seven or disease status (healthy   - Infected - the average injury) or ..

Examples of qualities that are subject to the rule is fully in human (hair smooth and frizz and their wavy hair and thalassemia).

Inheritance of non-Mendelian traits

Hereditary traits are traits that are determined genetically, and they are passed on from parents to offspring according to the rules of Mendelian and non-Mendelian genetics. However, most of the hereditary traits are not determined solely by genes; Rather, it is affected by both genes and the environment together, and in Mendelian inheritance, each gene has two forms of alleles; They are the dominant allele (A) and the recessive allele (a), and the hereditary trait is pure (two similar alleles, aa or AA) or impure (two different alleles Aa) and the Mendelian traits are the traits to which Mendel’s three laws apply,[2] while the non-Mendelian traits They are the traits that are not subject to Mendelian laws, and the following is an explanation of the inheritance of non-Mendelian traits:

Adjectives with incomplete masters

Some genetic traits follow the principle of incomplete dominance, meaning that there is no allele that is completely dominant over the other allele, and the presence of these two alleles may result in an intermediate trait between the two traits when both are present, instead of one allele that determines the trait completely. Crossing or cross-pollination of a plant with white flowers and a plant with red flowers to produce a new plant with pink flowers; It is an intermediate characteristic between the color of red flowers and the color of white flowers.

Co-dominant traits and multiple alleles

There are some genetic traits that are controlled by multiple alleles, that is, the gene for this trait is controlled by more than two alleles, and these traits are called co-dominant traits, meaning that there is no dominant allele and a recessive allele like Mendelian traits, but there are two or more alleles that appear Their effect at the same time jointly, for example in some types of chicken, the allele of black feathers is shared with the allele of white feathers, and a cross between a black hen and a white hen will lead to the appearance of chickens with black and white feathers together.

The rabbit's fur color gene is controlled by 4 disordered alleles, meaning that it is a co-dominant trait.

polygenic traits

Some genetic traits are polygenic; That is, a single genetic trait is controlled by a number of different genes, and in the inheritance of polygenic traits, there are no clear categories for the trait, but rather an apparent spectrum, and an example of it is the characteristic of skin pigmentation in humans, which is controlled by several different genes, and for this there is a spectrum of skin colors For humans, not just two different fixed colors (eg dark black leather, wheat leather, white leather, dark wheat leather and so on).


Human eye color is also polygenic, as a wide range of eye colors can appear (eg, dark blue, light blue, gray, black, brown and so on).

sex-related traits

Sex-linked genetic traits are traits associated with sex chromosomes, which are the chromosomes that determine the sex of humans and organisms; male or female, as these chromosomes carry a set of genes that control the genetic characteristics associated with them, and in humans there are two sex chromosomes; The X sex chromosome and the Y sex chromosome, and these traits are often carried on the X chromosome because it is larger in size than the Y chromosome. An example of a sex-linked trait is red-green color blindness, which is caused by a defect in one of the genes carried on the X chromosome, and is a common trait in Males more than females.

What are some common dominant traits in humans?

Additional information: Other examples of dominant traits include freckles, cleft chin and dimples. Almond-shaped eyes are dominant over round-shaped eyes. This feature is controlled by recessive alleles. Detached earlobes dominant over attached earlobes and right-handedness are dominant over left-handedness

What is an example of complete dominance in humans?

There are many examples of complete dominance in humans, including having specific hair color, skin pigment, and brown eyes. Not all examples of complete dominance are common though. Dwarfism also shows complete dominance, but it is rare.

Why Mendelian genetics cannot fully explain human health and behavior?

Eugenicists wrongly used simple dominant/recessive schemes to explain complex behaviors and mental illnesses — which we now know involve many genes. They also failed to account for environmental effects on human development.

Do Mendel's principles of genetics only apply to animals?

Mendel worked on pea plants, but his principles apply to traits in plants and animals – they can explain how we inherit our eye colour, hair colour and even tongue-rolling ability. Gregor Mendel (1822–1884) is known as the father of genetics.

Do all humans have the same traits?

We all have unique personalities. We are all different from each other. Each one of us represent a unique mix of different personality traits. No other person has the same mix of big five personality traits (and their facets) as you have.

Do all traits follow Mendelian rules?

The answer to that question is no, but many organisms do indeed show inheritance patterns similar to the seminal ones described by Mendel in the pea.

Are most human traits non-Mendelian?

Therefore no trait is purely Mendelian, but many traits are almost entirely Mendelian, including canonical examples, such as those listed below. Purely Mendelian traits are a minority of all traits, since most phenotypic traits exhibit incomplete dominance, codominance, and contributions from many genes.

What is Mendelian inheritance of human traits?

Mendelian inheritance refers to certain patterns of how traits are passed from parents to offspring. These general patterns were established by the Austrian monk Gregor Mendel, who performed thousands of experiments with pea plants in the 19th century.

What are the Mendelian principles in human genetics?

Mendel's conclusion was that every studied trait in offspring was dictated by a pair of factors, each being inherited from one parent [15]. Based on Mendel's research, three main principles were established, known as Mendel's laws of uniformity , gametes segregation, and independent assortment .

Are there Mendelian traits in humans?

Examples of human autosomal Mendelian traits include albinism and Huntington's disease. Examples of human X-linked traits include red-green colour blindness and hemophilia.

Does Mendelian genetics apply to humans?

Characteristics that are encoded in DNA are called genetic traits. Different types of human traits are inherited in different ways. Some human traits have simple inheritance patterns like the traits that Gregor Mendel studied in pea plants.

Mendelian traits in humans.. Different eye color because of the different composition of the iris and the amount of melanin

Mendelian traits in humans:

As in the case of (earlobe - the color of the eye - the form of thumb - the ability to bend the tongue)

The inheritance of eye color in humans:

Eye color difference due to the difference in the installation of the iris and the amount of melanin pigment.
Eye color nuances (Brown - Black - hazel ..) prevailed and blue eyes.

Why then the light color of the eye?

Scientists suggest that the reason behind this is a change resulting from the existence of a common ancestor that had a change in one of the genes that control melanin production. It is believed that this change or transformation caused a decrease in melanin production in the iris.
Therefore, the color of some eyes appears blue, green, or hazelnut in color, and the reason here is not the presence of a variety of color pigments, but rather the weakness of the melanin pigment. And when the melanin pigment in the eye is weak, the absorption of light is less. This means that the extra amount of light diffuses out of the iris and as it diffuses, the light is reflected differently from the color of the light spectrum. Therefore, the lack of melanin in the eyes gives them a blue color. And if the percentage of melanin increases slightly, the eye color becomes green or hazel.

There are several genes that determine eye color

Scientists thought that there was only one type of gene responsible for eye color. However, recent research has shown that there are approximately 16 different types of genes that could be responsible for determining eye color. This explains how two parents with the same eye color have a child with a different eye color.

When a baby is born, his eyes appear blue because the melanin pigment is still developing. Until he reaches the age of one year, the cells begin to form, that is, when the melanin pigment accumulates in the iris and makes the eye color darker.

Eye color varies in light of the climatic difference.

The melanin pigment present in the eyes, hair and skin acts as a protection against the harmful sun rays. For this reason, we find that the warmer regions such as Africa or Asia tend to have more brown eyes than the case in European regions. In Iceland, for example, very few people have brown eyes.
And when people move to geographical areas less exposed to the sun, the need for protection given by melanin pigment also decreases, and on this basis we understand that the evolution of our eye color is related to the movement of our ancestors from the colder regions of the globe.

The relationship between eye color and visual diseases

People with brown eyes are less likely to develop tumors, macular degeneration, or diabetic retinopathy. Ophthalmologists believe that the pigment melanin provides great protection for brown eyes.

Why is eye color not a Mendelian trait?

Although eye color is usually modeled as a simple, Mendelian trait, further research and observation has indicated that eye color does not follow the classical paths of inheritance. Eye color phenotypes demonstrate both epistasis and incomplete dominance.

Why is the iris different from person to person?

The pattern of your iris differs in each eye. This even holds true for identical twins. How does that happen? As the developing fetus opens and shuts its eyes in utero, iris tissue tightens and folds randomly, so no two can be the same.

What is it called when you have a different color around your iris?

Rather than have one distinct eye color, people with central heterochromia have a different color near the border of their pupils. A person with this condition may have a shade of gold around the border of their pupil in the center of their iris, with the rest of their iris another color.

What is it called when a person has irises of different colors?

What Is Heterochromia? Heterochromia is when a person's irises are different colors. There are a few kinds of heterochromia. Complete heterochromia is when one iris is a different color than the other. When part of one iris is a different color than the rest of it, this is called partial heterochromia.

What is the difference between polygenic and Mendelian inheritance?

Polygenic inheritance describes the inheritance of traits that are determined by more than one gene. These genes, called polygenes, produce specific traits when they are expressed together. Polygenic inheritance differs from Mendelian inheritance patterns, where traits are determined by a single gene.

Are there Mendelian traits in humans?

Examples of human autosomal Mendelian traits include albinism and Huntington's disease. Examples of human X-linked traits include red-green colour blindness and hemophilia.

What is polygenic vs Mendelian traits?

While Mendelian traits tend to be influenced by a single gene, the vast majority of human phenotypes are polygenic traits. The term polygenic means “many genes.” Therefore, a polygenic trait is influenced by many genes that work together to produce the phenotype.

What is melanin in eyes?

Melanin is a pigment that gives color to your eyes, hair and skin. Genes determine your eye color. The iris (the colored part of the eye) can range from light blue or gray to very dark brown, in a full spectrum of shades. No two people have the exact same color eyes.

Is different eye color a mutation?

What causes heterochromia? The most common cause of heterochromia is a genetic mutation that results in an individual born with two differently colored eyes. This mutation is not usually harmful and, as mentioned, usually does not influence the quality of vision.

What is the evolutionary reason for different eye colors?

One theory is the Vitamin D hypothesis, which is the idea that light colored skin, hair, and eyes co-evolved as humans moved into latitudes with shorter days, shorter summers, and therefore, less sunlight.

Is eye color polygenic or Mendelian?

polygenic trait

Genetic determination of eye color

It was originally thought that eye color was a simple Mendelian trait, meaning it was determined by a single gene, with brown being dominant and blue recessive. It is now clear that eye color is a polygenic trait, meaning it is determined by multiple genes.

Why is the color of the iris not the same on other people or races?

Eye color is determined by variations in a person's genes. Most of the genes associated with eye color are involved in the production, transport, or storage of a pigment called melanin. Eye color is directly related to the amount of melanin in the front layers of the iris.

Does Mendelian genetics apply to eye color?

In the most elementary form, the inheritance of eye color is classified as a Mendelian trait. On the basis of the observation of more than two phenotypes, eye color has a more complex pattern of inheritance. Eye color ranges include varying shades of brown, hazel, green, blue, gray, and in rare cases, violet and red.

Genetic counseling.. Predict genetic diseases that may occur to children resulting from a particular marriage

Important to predict the genetic diseases that may occur to children resulting from a particular marriage.
Genetic engineering can be used in the treatment of some diseases.
It is known that the genetic traits inherited rights affected by the environment If you encounter a suitable environment for her appearance they appear.

Genetic disorders in humans.. Down syndrome. Klinefelter syndrome. Thalassemia. Vinyl disease Kituoraa

Are diseases caused by change in the composition of the genetic material in human, both in the number of chromosomes or installed, and this is called (boom) 
1 - Down syndrome: 
Produces physical chromosome pair plus No. 21 where it becomes 3 chromosomes instead of 2, and its symptoms (short stature - Leather pagan eyelid - a widening of the distance between the eyes - poor mental powers - Age Palace - infertility).2 - Klinefelter syndrome:
Produces chromosome plus in the male sexual Rather than be installed male XY Becomes XXY And symptoms (increased breast size - genital atrophy - infertility) 
3 - Thalassemia: 
Results from the non-transformed fetal hemoglobin to adult hemoglobin during the first 6 months of a child's life. 
The symptoms of this disease (severe anemia - low growth - an enlarged spleen - a weakened immune system) 
* The individual with the disease H F H F                                                         
* Individual that H A H A 
* Capita average injury H A H F 
Where symbolized by the letter H To hemoglobin A character Allele is responsible for adult hemoglobin and character F Allele is responsible for fetal hemoglobin. 
4 - disease Vinyl Kituoraa: 
An infected person does not have the enzyme that converts the amino acid phenylalanine to the amino acid Tairosen causing severe mental retardation.

Sex-linked genetic traits.. Color blindness. Bleeding disease

Qualities are carrying their genes on chromosome especially sexual X Diseases such as color blindness and bleeding.
Color blindness:
Is the inability to distinguish red and green, where he sees the injured Colors one color is brown.
Bleeding disease:
Person with the disease blood clotting difficulty when an injury occurs and the cause of the disease is the lack of a type of protein is essential for clotting.

Importance of inherited blood groups.. Responsible for determining the sex of the baby is the man and not the mirror because the man has two different types of gametes

-1 Importance in forensic terms denies paternity, but not proven.
-2 Important in the transfer of blood from one person to another.
Each cell in the human body by 46 chromosome 23 pair of them 44 bodily chromosome (self) and a pair of sex chromosomes symbolizes him in the female XX In the male XY
Man produces two different types of gametes (sperm) one X chromosome And the other Y chromosome
Female produces one type of gametes (eggs) contain only the X chromosome .
Responsible for determining the sex of the baby is the man and not the mirror because the man has two different types of gametes.

Mendelian traits in human.. Skin color. The inheritance of blood groups

Most recipes non-Mendelian such as human genetics (the color of the skin - blood types)
1 - skin color:
There are included in human skin color so subject inherited skin color in humans to multiple genes where there are 3 pairs of genes control the color of human skin.
Black person AABBCC white person aabbcc and skin color depends on the number of alleles uppercase
2 - The inheritance of blood groups: Class world Landsteiner blood groups to (4) groups are A And BAB And O By the presence of antigen.
Antigen: is a protein that carries the red blood cell membrane
Blood Type
Generators antibody
Antibodies
Genetic compositions
A
A
B
I A I A Or I A i
B
B
A
I B I B Or I B i
AB
A And B
----
I A I B
O
------
A And B
ii
Inherited blood groups is subject to multiple alleles opposite as controls in the succession process (3) different alleles are as follows:
I A allele Controls the formation of antigen A
I B allele Controls the formation of antigen B
I allele Not be any generator against.

Experimental inoculation in genetics.. Testing individual possessing such prevailing ostensibly for their genetic compositions

Intended to test the individual possessing the capacity of prevailing ostensibly to know the composition is prevalent genetic hybrid or cushions pure. This is done Hybridization with individual possessing such recessive (because they always pure) If all members of the first generation carrying capacity prevailing (100% Bags) means that the individual laboratory Bags pure As if half of offspring carrying capacity prevailing and the other half carries such recessive 50% and 50% means that the individual a hybrid laboratory cushions.
When solving genetic following should be observed:
1 - convert any numbers in the matter to the ratios.
2 - If the ratio is 1:1, the one parents hybrid Bags and the other recessive.
3 - If the ratio 3:1, parents Bags hybrid x Bags hybrid.
4 - If the ratio was 100% pillow cushions, parents pure x cushions pure or hybrid or recessive.

The inheritance of multiple genes.. Inheriting multiple qualities that also called hereditary Quantity

Weights of the animals graded and graduated weights fruits of plants and animals and plants lengths scalable and intelligence of a human being graded and subject all these qualities to inherit multiple traits which are also called quantitative genetics.
Example Weight chicken:
If the weight of 1800 gm chicken and genetic AABBDD composition Every great character give a hen weight of 300 g
The hens small weight 600 g genetic makeup aabbdd Each character gives small chicken 100g.

Difficulties facing the study of human genetics.. The large number of chromosomes and the complexity of installation

1 - Longevity in human generation. 
2 - The small number of individuals resulting from mating in the same family. 
3 - The large number of chromosomes and the complexity of the installation. 
4 - Many of the attributes of the human subject of multiple genes. 
5 - Difficulty subjecting human genetic test or marriages determined by the researcher.

Follow steps Flower color inheritance in pea plant.. Recipe prevailed. Recipe recessive

1 - Mendel conducted humoral pollination between plants red color Flowers pure white color flowers plants (pure).
2 - Collect the seeds produced and planted and found that all plants resulting in the first generation color of red flowers.
3 - leave this plant self Vaccination then seeding resulting, and received 428 plant red flowers and 152 plant white flowers.
4 - Extract ratio 428/152 = 3/1
5 - Mendel repeated this experiment on other qualities, and received similar results.
6 - named Mendel character that appears in all members of the first generation (recipe prevalent) and as such anti (recessive recipe) which disappear in all members of the first generation.

Mendel's experiments in genetics at the plant peas.. Pure strain at Tzaugea giving individuals have the same qualities parents

Mendel studied seven recipes in the pea plant, namely:
Capacity
Well ileg
Position of Venus
Flower color
Form century
Color century
Form the seed
Color seed
Prevalent
Long
Side
Red
Smooth
Green
Smooth
Yellow
Recessive
Short
Terminal
White
Curly
Yellow
Curly
Green
Mendel initially sure of the purity of character studied by leaving plants inoculated himself (autoinoculation) for several generations in order to ensure a self-pollinating flowers covered with sacks of silk.
Pure strain:
A group of individuals of one type with virtual similar characteristics and at Tzaugea giving individuals have the same characteristics as the parents.

Mendelian traits in genetics and how inherited traits in pea plant

Mendel studied how inherited traits in pea plant and had been successful in the pea plant because of its qualities: 
1 - The possibility of self-pollination in flower, peas, as well as cross pollination because they flower hermaphrodite. 
2 - Bearing opposite qualities (opposite) that are easy to distinguish. 
3 - Easy peas cultivation and the speed of its growth. 
Palace life cycle (approximately 3 months).
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