3. Heredity
Heredity refers to the genetic heritage passed
down by our biological parents. It's why we look
like them! More specifically, it is the transmission of
traits from one generation to the next. These traits
can be physical, such as eye colour, blood type or
a disease.
4. The transmission of characters or
traits from parents to their offspring
(children) is termed as heredity.
Genetics is the study of heredity and
other variations.
5. Gregor Mendel: the 'father of genetics' In
the 19th century, it was commonly
believed that an organism's traits were
passed onto offspring in a blend of
characteristics 'donated' by each parent.
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14. Variation
Variation, in biology, any difference between cells,
individual organisms, or groups of organisms of any
species caused either by genetic differences
(genotypic variation) or by the effect of
environmental factors on the expression of the
genetic potentials (phenotypic variation).
15. Types of variation
THere are three sources of genetic variation: mutation,
gene flow, and sexual reproduction. A mutation is
simply a change in the DNA. Mutations themselves are
not very common and are usually harmful to a
population.The advantage of having variation within a population is that
some individuals will be better adapted to their environment than others. Those
individuals who are not well adapted to their environment are less likely to survive
and reproduce.
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17. Chromosomes and genes
A chromosome is a DNA (deoxyribonucleic acid) molecule with part or all of the
genetic material (genome) of an organism. Most eukaryotic chromosomes include
packaging proteins which, aided by chaperone proteins, bind to and condense the
DNA molecule to prevent it from becoming an unmanageable tangle.
A gene is the basic physical and functional unit of
heredity. Genes are made up of DNA. Some genes act
as instructions to make molecules called proteins.
However, many genes do not code for proteins.
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19. DNA
DNA or deoxyribonucleic acid is a long molecule that contains our unique genetic code.
Like a recipe book it holds the instructions for making all the proteins in our bodies.
20. Dominant traits and recessive traits
Dominant refers to the relationship between two versions of a gene. Individuals receive two
versions of each gene, known as alleles, from each parent. If the alleles of a gene are
different, one allele will be expressed; it is the dominant gene. The effect of the other allele,
called recessive.
21. Mendel’s
experment
Mendel is known as the father of
genetics because of his
groundbreaking work on inheritance
in pea plants 150 years ago.Mendel
began a series of experiments at the
monastery to find out how traits are
passed from generation to
generation. At the time, it was
thought that parents’ traits were
blended together in their progeny.
22. Mendel selected garden pea plant (Pisum sativum) for his
experiments because of the following characteristics :
1. The flowers are bisexual and naturally self pollinating.
2. They can be artificially cross-pollinated.
3. The offsprings produced after cross pollination are fertile.
4. Pea plant has several pairs of contrasting characters.
5. Flowers of pea plant are large enough for easy
emasculation.
6. It is a small herbaceous plant, so he could grow large
number of plants.
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27. Mendel’s laws
➢ Law of dominance
➢ Law of Segregation
➢ Law of Independent
Assortment.
28. Mendel's law of dominance states
that: “When parents with pure,
contrasting traits are crossed
together, only one form of trait
appears in the next generation. The
hybrid offsprings will exhibit only the
dominant trait in the phenotype.”
Law of dominance is known as the
first law of inheritance.
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30. Law of
Segregation
Character Traits Exist in Pairs that
Segregate at Meiosis. ... This is
the basis of Mendel's First Law,
also called The Law of Equal
Segregation, which states: during
gamete formation, the two alleles
at a gene locus segregate from
each other; each gamete has an
equal probability of containing
either allele.
31. The Law of Independent
Assortment states that
during a dihybrid cross
(crossing of two pairs of
traits), an assortment of
each pair of traits is
independent of the other. In
other words, during gamete
formation, one pair of trait
segregates from another pair
of traits independently.
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43. Heredity | Genetics Quiz
Practice Quiz for Mendel's Genetics
Genetics, Heredity Practice Test
https://www.quia.com/quiz/309732.html?AP_rand=148467367
44. EVOLUTION
In biology, evolution is the change in the characteristics of
a species over several generations and relies on the
process of natural selection. The theory of evolution is
based on the idea that all species?
are related and
gradually change over time.
three main types of evolution: divergent, convergent,
and parallel evolution.
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47. EVIDENCES OF EVOLUTION
There are five lines of evidence that
support evolution: the fossil record,
biogeography, comparative anatomy,
comparative embryology, and
molecular biology.
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49. Homologous organs
Homologous organs are defined as the organs of different animals
that are having a similar origin but differ in their functions.
50. Analogous organ :
Analogous organs are the opposite of
homologous organs, which have similar
functions but different origins. An example
of an analogous trait would be the wings of
insects, bats and birds that evolved
independently in each lineage separately
after diverging from an ancestor without
wings.
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54. HUMAN EVOLUTION
Human evolution is the evolutionary
process that led to the emergence of
anatomically modern humans, beginning
with the evolutionary history of
primates—in particular genus Homo—and
leading to the emergence of Homo sapiens
as a distinct species of the hominid family,
which includes the great apes.
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58. Artificial selection is the process in which human
preferences have a significant effect on the evolution
of a particular species.
Cabbage was produced by selecting a short petiole.
Broccoli was developed by selecting the arrested
flower development of wild cabbage. Another variety,
cauliflower, was developed by selecting sterile
flowers in the wild cabbage plant. Selection of
swollen parts of wild cabbage led to the evolution of
yet another variety known as kohlrabi. Similarly, kale
was developed by selecting large leaves.
