Tree Thinking
This word means belonging to the same group or family, or connected by common ancestors.
Related
Handout A: The one characteristic every animal on this cladogram shares.
Vertebrate (has a backbone)
This molecule carries the genetic instructions in every living organism, from bacteria to humans.
DNA
Capital letters stand for this kind of allele, the one with more influence.
Dominant
Larkey Key: A larkey's genotype is ee. What is its phenotype?
Gray eyes
A branching diagram that shows how organisms are related, based on the characteristics they share.
Cladogram
Handout A: List every characteristic the frog and the rabbit share.
Vertebrate, bony skeleton, four limbs
Threadlike structures in the nucleus made of tightly coiled DNA.
Chromosomes
When an organism's two alleles for a feature are different, like Ee.
Heterozygous
Larkey Key: A larkey has long legs. What is its genotype?
aa
On a cladogram, time moves in this direction.
Bottom (oldest) to top (present)
Handout B: Name every plant that has vascular tissue.
Club mosses, ferns, gymnosperms, flowering plants
A section of DNA that carries the code for making a protein.
Gene
An inherited characteristic or structure, like fur, eyes, or legs.
Feature
Larkey Key: A larkey is heterozygous for eye color. What is its phenotype?
Red eyes
On a cladogram, the circles (nodes) where two branches split apart represent these.
Common ancestors
Handout B: Which lettered circle is the most recent common ancestor of gymnosperms and flowering plants?
Circle F
Two different versions of the same gene, like E and e.
Alleles
The individual expression of a feature, like red eyes or gray eyes.
Trait
Larkey Key: A larkey has red eyes. What are its two possible genotypes?
EE or Ee
The single shared ancestor closest in time to two organisms, found where their branches first join.
Most recent common ancestor
Handout A: Is the bird more closely related to the alligator or the human?
The alligator
Genes carry the code for making these, which build the structures you see as traits.
Proteins
An organism's combination of alleles, written with letters like Ee.
Genotype
Larkey Key: A larkey is homozygous recessive for both legs and eyes. What is its phenotype?
Long legs and gray eyes