Transcript Variation and genotypes

Variation and genotypes
LO: How alleles cause variation through
sexual reproduction
LO: How environmental factors influence the
genotype to provide the phenotype
Keywords:
allele, genotype, homozygous, heterozygous,
dominant, recessive, chromosome, gene,
B
B
b
b
brown
brown
black
black
L
L
l
l
long tail
long tail
short tail
short tail
H
H
h
h
hairy chest hairy chest
bare chest bare chest
Place a tally mark against the
phenotype
Brown
Long tail
Hairy
Brown
Short tail
Hairy
Brown
Short tail
bare
Black
Long tail
Hairy
Black
Short tail
Hairy
Black
Short tail
bare
Variation
• The generation of variation is due to:
• The random production of gametes
shuffles the genotypes
• The random fertilisation process of sperm
and egg randomly combines genotypes
• This leads to a diverse population some
will be strong genetically others will be
genetically weak. The environment will
excerpt selection pressures and the fittest
will survive.
Dates for your diary
•
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1.
2.
3.
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After school revision sessions
Voluntary attendance 45 mins
WS3 Tuesday 21st October
WS3 Monday 10th November
WS3 Monday 17th November
15.45 – 16.30
Bring you ideas and requirements with
you I cannot plan the session so will
respond to your requests at the time
unless you give me advance notice.