y10 inheritance & species survival
TRANSCRIPT
Writing reasons why some survived and others did not.Why did were some eggs easily found and others not?Which eggs would be most likely to live on?Why, where, how?Is an Evolution of the eggs needed?
Think about colour, location, shape, size, environment, predators (you) access,
Write or draw an example of another situation where genes affect survival. Explain why, influences, result.
Natural Selection Individuals with these particular characteristics are
said to be better adapted to the environment. Individuals with unfavourable characteristics will
usually die before they are able to reproduce.
Revision
DNA (Deoxyribonucleic acid) Review A karyotype is the number and appearance
of chromosomes in the nucleus. It is the complete set of chromosomes in a
species, or an individual organism. A chromosome is an organized structure of
coiled DNA and protein found in cells.
DNA Review DNA Constructed of Rungs & Rails’ Rungs are a pair of bases
A (Adenine) is paired with T (Thymine) G (Guanine) is paired with C (Cytosine)
DNA is a BLUEPRINT of how to build the body.
It stores/determines the biological characteristics of any living thing
Cell replication The body grows and repairs itself through cell
division. A parent cell divides into 2 daughter cells A process know as mitosis for normal cells DNA is replicated and separated into 2 cells
so all the Blueprints/information is there. 1 Parent cell forms 2 Identical Daughter cells
GenesGenes are passed on through DNA.A long long strand of DNA twisted and
twisted form a chromosomeHow many Chromosomes do we have?46, 23 pairs.What can occur if cells have an extra
chromosome?
Dominance and recessive geneA DOMINANCE allele covers up the
recessive form.A DOMINANCE allele is
represented in CAPITALSA recessive allele is represented in
lower case
Phenotypes and genotypesPhenotype – is the physical
characteristic of the gene ie attached lobe
Genotype is the combination of alleles (genes) that make up the gene – represented in letters. LL, Ll (lL), ll
Phenotype – is the physical characteristic/appearance of the gene ie attached lobe
Genotype is the combination of alleles (genes) that make up the gene – represented in letters. LL, Ll (lL), ll
Question time Two black fish look the same but have
different genotypes. The fish with genotype BB is said to be homozygous, or pure breeder because both the alleles for the skin colour gene are the same. The other fish is said to be heterozygous or Hybrid, because its two alleles for skin colour gene are different.
What offspring can occur when the fish cross breed, that is BB & Bb.
What offspring can occur when 2 heterozygous breed?
Incomplete DominanceIncomplete dominance is a condition when neither
allele inherited is dominant or recessive over the other
This will result in a blend/fusion of characteristicsAn example of this is in snapdragons, a flower where
its colour can be red, pink, or white. A white (WW) snapdragon crossed with a red (RR)
snapdragon produces all pink offspring The heterozygous (RW) condition results in pink
flowers.
CodominanceWhen both alleles contribute to
the phenotype of an organismEx.) Speckled Chickens
Human Blood TypesPhenotype Genotype
A
B
AB
O
IAIA or IAi
IBIB or IBi
IAIB
ii
Genetics and the EnvironmentThe characteristics of any organism, is
not only determined by the genes it inherits
Characteristics are determined by interactions between genes and the environment
Ex.) genes may affect a plants height but the same characteristic is influenced by climate, soil conditions and availability of water
Genetics and the Environment – Evolution
The best adapted organisms are those that survive environmental changes and pass on favourable characteristics to their offspring
2 colour types of Frogs in the world. Green and earth.
Which frog would be more likely to be found in the outback? Why?
Which frog would be existiant in the forest? Why?
If all the forests died which frog would survive? Why?
Genetics and the Environment – Evolution
2 colour types of Frogs in the world. Green and earth.
Which frog would be more likely to be found in the outback? Why?
Which frog would be existiant in the forest? Why?
If all the forests died which frog would survive? Why?
Genetics and the Environment – Evolution
The Movie 300.Is this a form of Evolution or Selecting
genes?Would this lead a form of evolution?
Finished
Red hair is a recessive gene and Brown hair is a dominate gene.If your parents both have Brown hair is it possible for you to have red hair? Answer yes or no.Give Reasoning as to why and show diagram of how this can occur.Show one example of how it will not be possible for you to have red hair.