13 INHERITANCE Flashcards
Shape of DNA
Double Helix
Adenine pairing
Thymine
Thymine pairing
Adenine
Cytosine pairing
Guanine
Guanine
Pairing
Where are genes and chromosomes stored
Nucleus contains chromosomes on which genes are located
What is a nucleotide
Deoxyribose sugar, phosphate base, and nitrogenous base
What is the genome
The entire DNA of an organism
What is a gene
A section of a molecule of DNA that codes for a specific protein
Shape of RNA
Single stranded
Differences from DNA and RNA
- RNA is single stranded, wheras DNA is double strnaded
- DNA has deoxyribose sugar, wheras RNA has ribose sugar
- RNA has Uracil base, wheras DNA has thymine base
Adenine pairing in RNA
Uracil
Uracil pairing
Adenine
mRNA meaning
Messenger RNA
tRNA meaning
Transfer RNA
Where is mRNA made
Nucleus
Where is tRNA made
Cytoplasm
What is a codon
A sequence of 3 bases
Are chromosomes homologous or heterozygous
Homologous
What is an allele
A different version of a gene, which codes for a different form of protein
XX sex chromosomes meaning
Female
XY sex chromosomes meaning
Male
What is genetic variation
Organisms with different versions of genes to another individual - sexual reproduction, or mutation
What is environmental variation
When the environment affects the characteristics of an organism
What is a combination of environmental and genetic variation
When both genetic and environmental factors contribute to variation
Define an allele
A version of a gene
What does homozygous mean
Both chromosomes have the same allele - for offspring
In terms of alleles and inheritance, what does a dominant trait need
Only one allele present to be expressed
In terms of alleles and inheritance, what does a recessive trait need
Two alleles present to be expressed
What does heterozygous mean
Both parents contain one of each allele
What are most phenotypic features a result of
Polygenic inheritance
What is a genotype
The combination of alleles
What is a phenotype
What is physically expressed
If two heterozygous parents have a faulty gene that is recessive, what is their offspring called if they have the gene as a phenotype
Homozygous resessive
What is codominance
When both alleles contribute to the phenotype of the organism
What pair of chromosomes determine the gender of offspring
23rd
Describe Darwin’s theory of natural selection
- Variation occurs due to mutations
- Individuals with better speicialisations survive to reproduce
- Pass on the advantageous alleles to the next generations
- Offspring inherit advatageous characteristics
- Less favorouble alleles become less common
- Repeats for generations
- Organisms with specialisations become different species
