Phenotype
-an organism’s evident traits such as skin color or eye color
Genotype
an organisms hereditary makeup
An organisms genotype doesn’t always match up with their phenotype
T/F
True
An organisms genotype does always match up with their phenotype
T/F
False
Allele
Allele biological different forms of a given gene
What causes organisms genotypes to not match with their phenotypes?
alleles cause organisms genotypes to not always match up with their phenotypes because of dominant and recessive genes
How can an organism have a recessive trait
an organism can only have recessive traits if both alleles are recessive
Example of phenotype not matching gene types
Example human blood type has 3 alleles and can have 6 genotypes because of the combination of genes but humans only have 4 phenotypes because of codominant alleles
Why are there variations in humans?
Humans vary due to genetic adaptations and natural selection
Adaptation
the process by which organisms cope with environmental stress
Natural Selection
the process by which nature chooses the forms most fit to survive and reproduce
What occurs across generations and what occurs along life time?
Genotypes vs phenotypical adaptation
Genetic adaptations occur across generations
Phenotypical adaptations occur in an individual’s life time
Thomson’s nose rule
Average nose length increases in cold or arid areas
Begmann’s rule: larger bodies are found in colder areas and smaller ones are in warmer areas.
What is Allen’s rule?
Protruding body parts are bigger in warmer areas
This rule explains how body adaptations can vary with climate.
Name an example of genetic adaptation.
This adaptation can occur in response to environmental conditions.
What is melanin?
A chemical substance manufactured in the outer layer of our skin to protect us from ultraviolet radiation
Melanin plays a crucial role in skin protection.
What condition is caused by a lack of melanin?
Rickets
Rickets is a disease that affects bone development in children.
What is the informal rank in the taxonomic hierarchy below subspecies called?
Race
The concept of race has evolved and is often debated in terms of its validity.
How have classifications of race changed over time?
They became divided into more and more categories
This reflects the complexity of human genetic diversity.