Cell Division Mitosis & Meiosis. Mitosis cell division somatic cell (body cell) The form of cell...
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Cell Division Mitosis & Meiosis
Cell Division Mitosis & Meiosis. Mitosis cell division somatic cell (body cell) The form of cell division by which a eukaryotic somatic cell (body cell)
Mitosis cell division somatic cell (body cell) The form of cell
division by which a eukaryotic somatic cell (body cell) duplicates.
Mitosisasexual reproduction. Mitosis is asexual reproduction. Cell
division Cell division is the continuation of life based on the
reproduction of cells.
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Mitosis each human body cell has 46 chromosomes 46 chromosomes
Liver Cell 46 chromosomes 46 chromosomes two identical daughter
cells Liver Cell (Parent cell)
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What Is A Chromosome? chromosome DNA. A chromosome is a very
long, continuous piece of DNA. Chromosomes contain many genes.
Genes are the units of heredity in organisms. DNA double helix
chromosome
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Meiosis Meiosis is the process of cell division that only
occurs in gametes or sex cells(egg & sperm). During meiosis, a
cell produces 4 gametes with half the number of chromosomes in each
gamete. The traits are distributed randomly in the newly formed
gametes.
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Number of Chromosomes in some Species of Animals Species# #
Fruit fly8Guinea Pig16 Dove16Snail24 Earthworm36Tibetan fox36
Cat38Pig38 Mouse40Rat42 Rabbit44Syrian hamster44 Hare46Human46
Gorilla48Sheep54 Elephant56Cow60 Donkey62Horse64 Dog78Chicken78
Carp104Butterflies380
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23 pairs (46) of chromosomes in human FemaleMale
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Genes & Heredity Why Do I Look Like My Parents???
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Question: Why Dont You Look Like a rhinoceros?
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Answer: Because _______. Heredity is the passing of traits from
parents to offspring. Traits and characteristics pass from parents
to offspring through genes.
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Genetics Terms Alleles: the different forms of a gene. Dominant
allele: an allele whose trait always shows up when it is present.
Recessive allele: an allele that is masked when a dominant allele
is present.
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Homozygous vs. Heterozygous If both the alleles inherited by
the zygote(fertilized egg) for a particular characteristic are the
same they are called homozygous. homozygous If they are different
from each other they are called heterozygous. heterozygous
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Homologous Chromosomes? What the Each set of chromosome is a
homologous pair Homologous chromosomes chromosomes which contain
the same genes, one from each parentHomologouschromosomes
Homologous chromosomes look alike with similar information stored
on them One member of each homologous pair is inherited from each
parent through egg or sperm.
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Homologous Chromosomes =( Location )
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Dominant Allele vs. Recessive Allele
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Genotype & Phenotype A set of alleles inherited by an
individual is called a genotype.genotype The way the genes express
themselves in the individual's appearance is their
phenotype.phenotype
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Dominant & Recessive Traits Some traits show more often
than other traits. The traits that show often are called dominant
traits. Those traits that dont show often are recessive
traits.
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Genotype & Phenotype Both mother and father are
heterozygous for tongue rolling. Genotype: heterozygous alleles
(one dominant & one recessive) Phenotype: Ability to roll
tongue
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Albino snake, a recessive trait of not having colors
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Attached earlobe vs. free (or detached) earlobe Attached is a
recessive trait
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Black Eyes Tongue Rolling Dark Hair Curly Hair Mid- finger Hair
Widows Peak Some Dominant Traits
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Punnett square Punnett Squares are diagrams used to help us to
figure out how inherited traits (characteristics) will be
distributed Dominant trait is written by capital letter (A)
Recessive trait is written by lower case letter (a)
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Punnett square Both parents birds are homozygous, with the red
bird having 2 dominant alleles, and the blue bird having 2
recessive alleles. There is only one possible genotype for all the
offspring, and that is heterozygous. What is the phenotype of the
offspring? ______
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Practice with Punnett Square In rabbits, black fur is dominant
to white fur. A male rabbit with BB genotype and a female with a Bb
genotype are crossed. 1.What is their phenotype? 2.What are the
possible genotypes and phenotypes of the offspring? (Show using a
Punnett square) 3.What is the percent chance for each type?
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Questions- page 19L Copy & answer 1.What is heredity?
2.What is genetics? 3.Who was Gregor Mendel? 4.What type of
organism did he work on? 5.What does true-breed mean? 6.What does
self-pollinate mean? 7.What is offspring? 8.In genetics, what is P,
F 1, F 2 ? 9.What does cross-pollination mean? 10.Define dominant
& recessive.
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Inside the nucleus of a cell long strings of DNA are coiled up
and spooled onto chromosomes, and on each chromosome there are
several thousand genes - shorter sections of DNA which act as a
code for a particular characteristic. Since we inherit particular
chromosomes through the egg and sperm, we also inherit the
particular characteristics coded for by the genes on those
chromosomes. chromosomesgenes