B13 Flashcards
(30 cards)
What is asexual reproduction?
Identical offspring from one parent and no gametes are fused so no genetic info is mixed.
What is sexual reproduction?
Two parents gametes fuse so therefore genetic info is mixed and produces off spring.
Mixing of genetic info leads to what?
Variation.
What is meiosis?
Cell division which separates to produce 4 genetically different gametes.
What is mitosis?
Cell division which separates to produce 2 genetically different gametes.
Define DNA.
a polymer made up of two strands forming a double helix.
Define genome.
Combination of alleles an organism has which contribute to the phenotype.
Name the bases that go together.
A&T
C&G
What is a polymer?
molecule made from many smaller molecules called monomers that are linked together.
What are proteins?
Polymer molecules made from amino acids that have many roles including: enzymes, hair and haemoglobin.
How many chromosomes are there in one human?
23pairs
What is a gene?
A length of DNA that codes for a protein.
Define triplet.
Instruction to add one amino acid to protein.
What is a nucleotide?
Small DNA molecule is made of.
Name the order in which you draw a genetic cross diagram.
Parents Genotype Phenotype Gametes Punnet Square
Define zygote.
Forms from the fusion of gametes.
Define allele.
Different variations of a gene.
What is meant by dominant?
Alleles that are always expressed in the phenotype.
What is meant by recessive?
Alleles that are only expressed in the phenotype if homozygous.
Define phenotype.
Characteristics of an organism due to its genome or environment.
What does homozygous mean?
When the two alleles present are identical.
What does heterozygous mean?
When the two alleles present are not identical.
Name 2 inherited disorders.
Polydactyly
Cystic Fibrosis
Explain polydactyly.
Born with extra fingers.
