This pdf comprises of Basic of Genetics: Purpose: To convey that “Genetics is to biology what Newton’s
laws are to Physical Sciences”. Mendel’s laws, Concept of segregation and
independent assortment. Concept of allele. Gene mapping, Gene
interaction, Epistasis. Meiosis and Mitosis be taught as a part of
genetics. Emphasis to be give not to the mechanics of cell division nor the
phases but how genetic material passes from parent to offspring. Concepts
of recessiveness and dominance. Concept of mapping of phenotype to
genes. Discuss about the single gene disorders in humans. Discuss the
concept of complementation using human genetics.
A short Introduction to DNA and the structure of DNA. It also explains base pairing and Chargaff's rule. It informs you of who built the first model of DNA using wire and tin to show a description of how DNA looks like.
A short Introduction to DNA and the structure of DNA. It also explains base pairing and Chargaff's rule. It informs you of who built the first model of DNA using wire and tin to show a description of how DNA looks like.
Molecular biology is the study of biology at a molecular level.
In broad sense, the study of gene structure and functions at the molecular level to understand the molecular basis of hereditary, genetic variation, and the expression patterns of genes.The field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry.
This power point presentation is an attempt to present some direct and some indirect evidences in favour of DNA as genetic material. Very few organisms have RNA as genetic material for example plant virus and some bacteriophages
NCERT Books Class 12 Biology Chapter 5 Principles of InheritanceExplore Brain
NCERT Books Class 12 Biology Chapter 5
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Molecular biology is the study of biology at a molecular level.
In broad sense, the study of gene structure and functions at the molecular level to understand the molecular basis of hereditary, genetic variation, and the expression patterns of genes.The field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry.
This power point presentation is an attempt to present some direct and some indirect evidences in favour of DNA as genetic material. Very few organisms have RNA as genetic material for example plant virus and some bacteriophages
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NCERT Books Class 12 Biology Chapter 5
Principles of Inheritance
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Genetics- Chapter 5 - Principles of inheritance and variation.docxAjay Kumar Gautam
Genetics is a branch of biology concerned with the study of genes, genetic variation, and heredity in organisms. Though heredity had been observed for millennia, Gregor Mendel, Moravian scientist and Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene.
Genetics is a branch of biology concerned with the study of genes, genetic variation, and heredity in organisms. Though heredity had been observed for millennia, Gregor Mendel, Moravian scientist and Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene.
Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded beyond inheritance to studying the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the context of a population. In science and especially in mathematical studies, a variational principle is one that enables a problem to be solved using calculus of variations, which concerns finding functions that optimize the values of quantities that depend on those functions.
LIKE BEGETS LIKE, which means young one resemble their parents, (MONOHYBRID CROSS & DIHYBRID CROSS) is the well-known dogma associated with heredity. Each species has similarities among themselves due to the cause of heredity. W.Bateson was the first one to coin the term genetics in 1905. It is derived from the greek word “genesis” means to grow into or to become . in other word, genetics is the study of heredity and variation.
https://thegeneralscience.com/monohybrid-and-dihybrid-cross/
LIKE BEGETS LIKE, which means young one resemble their parents, (MONOHYBRID CROSS & DIHYBRID CROSS) is the well-known dogma associated with heredity. Each species has similarities among themselves due to the cause of heredity. W.Bateson was the first one to coin the term genetics in 1905. It is derived from the greek word “genesis” means to grow into or to become . in other word, genetics is the study of heredity and variation.
Understanding disasters and hazards and related issues social and environmental. Risk and Vulnerability. Types of Disasters. Impact and Preventive Issues
Green Chemistry: Definition and Concepts of green chemistry, principles of green
chemistry, waste or pollution prevention hierarchy, green chemistry and sustainability
development, use of alternative feed stock (Bio fuel), green solvents, alternative sources of
energy: use of microwaves and ultrasonic energy
Engineering Materials:
Portland Cement: Definition, manufacturing by Rotary Kiln, role of gypsum, chemistry of
setting and hardening of cement.
Glass: Definition, manufacturing by tank furnace, significance of annealing, types and
properties of soft glass, hard glass, borosilicate glass.
Lubricants: Classification, mechanism, properties; viscosity and viscosity index, flash and
fire point, cloud and pour point.
Corrosion: Definition and significance of corrosion, mechanism of chemical (dry) and
electrochemical (wet) corrosion, galvanic corrosion, concentration corrosion and pitting
corrosion. Protection from corrosion; protective coatings-galvanization and tinning, cathodic
protection, sacrificial anode modifications in design.
Eco Bricks: Ultimate way to make Plastic and Polythene free EnvironmentDr. Arun Sharma
EcoBricks prevent plastic waste from disrupting the ecosystem: Usually, when thrown away, plastic breaks down into tiny pieces and contaminates the area where it is. EcoBricks seal the plastic away preventing the buildup of toxic gases emitted during the degradation of the plastic, such as methane.
Microbiology: Concept of single celled organisms. Concept of species and
strains. Identification and classification of microorganisms. Microscopy.
Ecological aspects of single celled organisms. Sterilization and media
compositions. Growth kinetics.
Metabolism for Engineers (Useful for B.Tech., B.E. students)Dr. Arun Sharma
Metabolism: Purpose: The fundamental principles of energy transactions
are the same in physical and biological world. Thermodynamics as applied
to biological systems. Exothermic and endothermic versus endergonic and
exergonic reactions. Concept of Keq and its relation to standard free
energy. Spontaneity. ATP as an energy currency. This should include the
breakdown of glucose to CO2 + H2O (Glycolysis and Krebs cycle) and
synthesis of glucose from CO2 and H2O (Photosynthesis). Energy yielding
and energy consuming reactions. Concept of Energy charge.
Macromolecular Analysis (Biology for Engineers)Dr. Arun Sharma
Purpose: To analyse biological processes at the
reductionistic level. Proteins- structure and function. Hierarch in protein
structure. Primary secondary, tertiary and quaternary structure. Proteins
as enzymes, transporters, receptors and structural elements.
Quantum dots: A Novel Approach for Designing BiosensorsDr. Arun Sharma
Quantum Confinement Effect, Synthesis and Characterization, Band Gap, Fluorescence, Biosensors, Electrochemcial immunosensing, Bioconjugation and future outlook
Genetic Information Transfer (Biology for Engineers)Dr. Arun Sharma
Information Transfer: Purpose: The molecular basis of coding and
decoding genetic information is universal. Molecular basis of information
transfer. DNA as a genetic material. Hierarchy of DNA structure- from
single stranded to double helix to nucleosomes. Concept of genetic code.
Universality and degeneracy of genetic code. Define gene in terms of
complementation and recombination.
Enzymes for Engineers, Biologists, Physicists and ChemistsDr. Arun Sharma
Enzymes: Purpose: To convey that without catalysis life would not have
existed on earth. Enzymology: How to monitor enzyme catalysed reactions.
How does an enzyme catalyse reactions? Enzyme classification. Mechanism
of enzyme action. Discuss at least two examples. Enzyme kinetics and
kinetic
How does an enzyme catalyse reactions? Enzyme classification. Mechanism
of enzyme action. Discuss at least two examples. Enzyme kinetics and
kinetic
Composting,
vermicomposting, biogas production, thermal treatment, incineration,
pyrolysis, gasification, biological treatment, Sanitary land filling, land fill leachate and gas management Latest Advances and Rules related to SWM, Hazardous Waste,
Plastic Waste and E-Waste Management
This ppt explains about Waste, Types of Waste, Waste Management, Solid Waste, Classification, Solid Waste Management, Hazardous Waste Types, Factors affecting generation of waste, Traditional methods of waste collection and disposal
This ppt explains basics of corrosion, its significance, Mechanism of electrochemical and chemical corrosion, Cathodic protection, Anodic protection, Sacrificial protection, Galvanization, Concentration Corrosion, Pitting Corrosion and also describe about the prevention and control of corrosion with respect to protective coatings and modification in design.
Online aptitude test management system project report.pdfKamal Acharya
The purpose of on-line aptitude test system is to take online test in an efficient manner and no time wasting for checking the paper. The main objective of on-line aptitude test system is to efficiently evaluate the candidate thoroughly through a fully automated system that not only saves lot of time but also gives fast results. For students they give papers according to their convenience and time and there is no need of using extra thing like paper, pen etc. This can be used in educational institutions as well as in corporate world. Can be used anywhere any time as it is a web based application (user Location doesn’t matter). No restriction that examiner has to be present when the candidate takes the test.
Every time when lecturers/professors need to conduct examinations they have to sit down think about the questions and then create a whole new set of questions for each and every exam. In some cases the professor may want to give an open book online exam that is the student can take the exam any time anywhere, but the student might have to answer the questions in a limited time period. The professor may want to change the sequence of questions for every student. The problem that a student has is whenever a date for the exam is declared the student has to take it and there is no way he can take it at some other time. This project will create an interface for the examiner to create and store questions in a repository. It will also create an interface for the student to take examinations at his convenience and the questions and/or exams may be timed. Thereby creating an application which can be used by examiners and examinee’s simultaneously.
Examination System is very useful for Teachers/Professors. As in the teaching profession, you are responsible for writing question papers. In the conventional method, you write the question paper on paper, keep question papers separate from answers and all this information you have to keep in a locker to avoid unauthorized access. Using the Examination System you can create a question paper and everything will be written to a single exam file in encrypted format. You can set the General and Administrator password to avoid unauthorized access to your question paper. Every time you start the examination, the program shuffles all the questions and selects them randomly from the database, which reduces the chances of memorizing the questions.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
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Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
1. Genetics is a branch of biology concerned with the study of
genes, genetic variation, and heredity in organisms.
Genetics
Father of Genetics
Gregor Johann Mendel
2. Purpose to convey that genetics is to biology
that Newton's laws are to physical science
The work of Mendel and others who followed him gave us an idea of inheritance patterns.
However the nature of those ‘factors’ which determine the phenotype was not very clear.
As these ‘factors’ represent the genetic basis of inheritance, understanding the structure of
genetic material and the structural basis of genotype and phenotype conversion became
the focus of attention in biology for the next century. The entire body of molecular biology
was a consequent development with major contributions from Watson, Crick, Nirenberg,
Khorana, Kornbergs (father and son), Benzer, Monod, Brenner, etc. A parallel problem being
tackled was the mechanism of evolution. Awareness in the areas of molecular genetics,
structural biology and bio informatics have enriched our understanding of the molecular basis
of evolution. In this unit the structure and function of DNA and the story and theory of
evolution have been examined and explained.
3. Have you ever wondered why an elephant always gives birth only to a
baby elephant and not some other animal? Or why a mango seed forms
only a mango plant and not any other plant? Given that they do, are the
offspring identical to their parents? Or do they show differences in some
of their characteristics? Have you ever wondered why siblings
sometimes look so similar to each other? Or sometimes even so
different? These and several related questions are dealt with,
scientifically, in a branch of biology known as Genetics. This subject
deals with the inheritance, as well as the variation of characters from
parents to offspring. Inheritance is the process by which characters are
passed on from parent to progeny; it is the basis of heredity. Variation is
the degree by which progeny differ from their parents. Humans knew
from as early as 8000-1000 B.C. that one of the causes of variation was
hidden in sexual reproduction.
4. They exploited the variations that were naturally present in the wild populations of plants and
animals to selectively breed and select for organisms that possessed desirable characters. For
example, through artificial selection and domestication from ancestral wild cows, we have
well-known Indian breeds, e.g., Sahiwal cows in Punjab. We must, however, recognise that
though our ancestors knew about the inheritance of characters and variation, they had very
little idea about the scientific basis of these phenomena.
8. Steps in making a cross in pea
Gregor Johann Mendel Experiment
Male Sex Symbol
Female Sex Symbol
9. MENDEL’S LAWS OF INHERITANCE
It was during the mid-nineteenth century that headway was made in the
understanding of inheritance. Gregor Mendel, conducted hybridisation
experiments on garden peas for seven years (1856-1863) and proposed
the laws of inheritance in living organisms. During Mendel’s
investigations into inheritance patterns it was for the first time that
statistical analysis and mathematical logic were applied to problems in
biology. His experiments had a large sampling size, which gave greater
credibility to the data that he collected. Also, the confirmation of his
inferences from experiments on successive generations of his test
plants, proved that his results pointed to general rules of inheritance
rather than being unsubstantiated ideas.
10. Mendel investigated characters in the garden pea plant that were
manifested as two opposing traits, e.g., tall or dwarf plants, yellow or
green seeds. This allowed him to set up a basic framework of rules
governing inheritance, which was expanded on by later scientists to
account for all the diverse natural observations and the complexity
inherent in them. Mendel conducted such artificial pollination/cross
pollination experiments using several true-breeding pea lines. A true
breeding line is one that, having undergone continuous self-pollination,
shows the stable trait inheritance and expression for several
generations. Mendel selected 14 true-breeding pea plant varieties, as
pairs which were similar except for one character with contrasting traits.
Some of the contrasting traits selected were smooth or wrinkled seeds,
yellow or green seeds, inflated (full) or constricted green or yellow pods
and tall or dwarf plants.
11. INHERITANCE OF ONE GENE
Let us take the example of one such hybridisation
experiment carried out by Mendel where he crossed tall
and dwarf pea plants to study the inheritance of one gene.
He collected the seeds produced as a result of this cross
and grew them to generate plants of the first hybrid
generation. This generation is also called the Filial1 progeny
or the F1 . Mendel observed that all the F1 progeny plants
were tall, like one of its parents; none were dwarf. He made
similar observations for the other pairs of traits – he found
that the F1 always resembled either one of the parents, and
that the trait of the other parent was not seen in them.
12. Mendel then self-pollinated the tall F1 plants and to his surprise found
that in the Filial2 generation some of the offspring were ‘dwarf’; the
character that was not seen in the F1 generation was now expressed.
The proportion of plants that were dwarf were 1/4th of the F2 plants
while 3/4th of the F2 plants were tall. The tall and dwarf traits were
identical to their parental type and did not show any blending, that is all
the offspring were either tall or dwarf, none were of in between.
Similar results were obtained with the other traits that he studied: only
one of the parental traits was expressed in the F1 generation while at
the F2 stage both the traits were expressed in the proportion 3:1. The
contrasting traits did not show any blending at either F1 or F2 stage.
Concept of Segregation and independent assortment
13. Based on these observations, Mendel proposed that
something was being stably passed down, unchanged, from
parent to offspring through the gametes, over successive
generations. He called these things as ‘factors’. Now we call
them as genes. Genes, therefore, are the units of inheritance.
They contain the information that is required to express a
particular trait in an organism. Genes which code for a pair of
contrasting traits are known as alleles, i.e., they are slightly
different forms of the same gene. If we use alphabetical
symbols for each gene, then the capital letter is used for the
trait expressed at the F1 stage and the small alphabet for the
other trait.
14. For example, in case of
the character of height,
T is used for the Tall
trait and t for the
‘dwarf’,
and T and t are alleles
of each other.
16. Hence, in plants the pair of alleles for height would be TT, Tt
or tt. Mendel also proposed that in a true breeding, tall or
dwarf pea variety the allelic pair of genes for height are
identical or homozygous, TT and tt, respectively. TT and tt
are called the genotype of the plant while the descriptive
terms tall and dwarf are the phenotype. What then would be
the phenotype of a plant that had a genotype Tt?
As Mendel found the phenotype of the F1 heterozygote Tt to
be exactly like the TT parent in appearance, he proposed
that in a pair of dissimilar factors, one dominates the other
(as in the F1 ) and hence is called the dominant factor while
the other factor is recessive.
17. In this case T (for tallness) is dominant over t (for dwarfness), that is
recessive. He observed identical behaviour for all the other
characters/trait-pairs that he studied. It is convenient (and logical) to
use the capital and lower case of an alphabetical symbol to remember
this concept of dominance and recessiveness. (Do not use T for tall and
d for dwarf because you will find it difficult to remember whether T
and d are alleles of the same gene/character or not). Alleles can be
similar as in the case of homozygotes TT and tt or can be dissimilar as
in the case of the heterozygote Tt.
Since, the Tt plant is heterozygous for genes controlling one character
(height), it is a monohybrid and the cross between TT and tt is a
monohybrid cross.
Concept of Allele and Gene Mapping
18. Epistasis, Meiosis and Mitosis be taught as a part of
Genetics. Emphasis to be given not to the
mechanism of Cell Division nor the phases but how
genetic material passes from parent to offspring
From the observation that the recessive parental trait is expressed
without any blending in the F2 generation, we can infer that, when the
tall and dwarf plant produce gametes, by the process of meiosis, the
alleles of the parental pair separate or segregate from each other and
only one allele is transmitted to a gamete. This segregation of alleles is a
random process and so there is a 50 per cent chance of a gamete
containing either allele, as has been verified by the results of the
crossings.
19. In this way the gametes of the
tall TT plants have the allele T
and the gametes of the dwarf
tt plants have the allele t.
During fertilisation the two
alleles, T from one parent say,
through the pollen, and t
from the other parent, then
through the egg, are united to
produce zygotes that have
one T allele and one t allele.
20. Figure 3
In other words the hybrids
have Tt. Since these hybrids
contain alleles which express
contrasting traits, the plants
are heterozygous. The
production of gametes by the
parents, the formation of the
zygotes, the F1 and F2 plants
can be understood from a
diagram called Punnett
Square.
21. It was developed by a British geneticist, Reginald C. Punnett. It is a
graphical representation to calculate the probability of all possible
genotypes of offspring in a genetic cross. The possible gametes are
written on two sides, usually the top row and left columns. All possible
combinations are represented in boxes below in the squares, which
generates a square output form. The Punnett Square shows the parental
tall TT (male) and dwarf tt (female) plants, the gametes produced by
them and, the F1 Tt progeny. The F1 plants of genotype Tt are self-
pollinated. The F1 plant of the genotype Tt when self-pollinated,
produces gametes of the genotype T and t in equal proportion. When
fertilisation takes place, the pollen grains of genotype T have a 50 per
cent chance to pollinate eggs of the genotype T, as well as of genotype t.
Also pollen grains of genotype t have a 50 per cent chance of pollinating
eggs of genotype T, as well as of genotype t.
22. As a result of random fertilisation, the resultant zygotes can be of the
genotypes TT, Tt or tt. From the Punnett square it is easily seen that
1/4th of the random fertilisations lead to TT, 1/2 lead to Tt and 1/4th to
tt. Though the F1 have a genotype of Tt, but the phenotypic character
seen is ‘tall’. At F2 , 3/4th of the plants are tall, where some of them are
TT while others are Tt. Externally it is not possible to distinguish
between the plants with the genotypes TT and Tt. Hence, within the
genopytic pair Tt only one character ‘T ’ tall is expressed. Hence the
character T or ‘tall’ is said to dominate over the other allele t or ‘dwarf’
character. It is thus due to this dominance of one character over the
other that all the F1 are tall (though the genotype is Tt) and in the F2
3/4th of the plants are tall (though genotypically 1/2 are Tt and only
1/4th are TT).
23. This leads to a phenotypic ratio of 3/4th tall : (1/4 TT + 1/2 Tt)
and 1/4th tt, i.e., a 3:1 ratio, but a genotypic ratio of 1:2:1.
The 1/4 : 1/2 : 1/4 ratio of TT: Tt: tt is mathematically
condensable to the form of the binomial expression (ax +by)2
that has the gametes bearing genes T or t in equal frequency
of ½. The expression is expanded as given below :
(1/2T + 1/2 t)2 = (1/2T + 1/2t) X (1/2T + 1/2t) =
1/4 TT + 1/2Tt + 1/4 tt Mendel self-pollinated the F2 plants
and found that dwarf F2 plants continued to generate dwarf
plants in F3 and F4 generations. He concluded that the
genotype of the dwarfs was homozygous – tt. What do you
think he would have got had he self-pollinated a tall F2 plant?
24. From the preceeding paragraphs it is clear that though the genotypic
ratios can be calculated using mathematical probability, by simply
looking at the phenotype of a dominant trait, it is not possible to know
the genotypic composition. That is, for example, whether a tall plant
from F1 or F2 has TT or Tt composition, cannot be predicted. Therefore,
to determine the genotype of a tall plant at F2 , Mendel crossed the tall
plant from F2 with a dwarf plant. This he called a test cross.
In a typical test cross an organism (pea plants here) showing a dominant
phenotype (and whose genotype is to be determined) is crossed with
the recessive parent instead of self-crossing. The progenies of such a
cross can easily be analysed to predict the genotype of the test
organism. The results of typical test cross where violet colour flower (W)
is dominant over white colour flower (w).
26. Using Punnett square, try to find out the nature of offspring
of a test cross. What ratio did you get? Using the genotypes of
this cross, can you give a general definition for a test cross?
Based on his observations on monohybrid crosses Mendel
proposed two general rules to consolidate his understanding
of inheritance in monohybrid crosses. Today these rules are
called the Principles or Laws of Inheritance: the First Law or
Law of Dominance and the Second Law or Law of Segregation.
Concept of Recessiveness and Dominance
31. In this case, the father — has a 50% chance of having an affected child
with one mutated gene (dominant gene) and a 50% chance of having an
unaffected child with two normal genes. Huntington's disease is caused
by an inherited defect in a single gene.
Complications:
After Huntington's disease starts, a person's functional abilities
gradually worsen over time. The rate of disease progression and
duration varies. The time from disease emergence to death is often
about 10 to 30 years. Huntington's disease usually results in death
within 10 years after symptoms develop. The clinical depression
associated with Huntington's disease may increase the risk of suicide.
32. Huntington’s Disease (HD) is a rare
genetic neuro-degenerative brain
disease, which gradually causes a
person to lose control of their
thoughts, feelings, behaviour,
movement, communication and
the ability to swallow.
33. Huntington’s disease (HD) is a rare
genetic disorder that causes the
breakdown of nerve cells in the brain.
34.
35. Concept of Complementation Using Human Genetics
Many genetic
disorders result
from gene changes that
are present in essentially
every cell in the body. As
a result,
these disorders often
affect many body
systems, and most
cannot be cured.