Vocabulary
An instruction for making a protein molecule
gene
Can organisms have different proteins in their cells for a particular feature?
Yes
Two spiders have the same parents and they were raised in the same environment. Are they guaranteed to have the same traits?
No
True or false: Most organisms inherit more copies of a gene from one parent than the other.
Why?
False. Organisms inherit one copy from mom and one copy from dad
A type of large molecule that performs important functions inside organisms
Protein
How many copies do you have of each gene?
Two
A spider is homozygous for silk flexibility. How many different silk flexibility proteins does it have in its cells?
One
True or false: The proteins in your cells are determined by what proteins you eat in your environment.
Why?
False. Your proteins are determined by your genes
to receive genes from parents
inherit
What determines an organisms TRAITS?
Its protein molecules
Two spiders have different parents, but they have the same silk flexibility. How is this possible?
They must have the same silk flexibility proteins
True or false: Two organisms with the same proteins for a trait will always have the same trait because the proteins connect the same way, even if the organisms have different parents.
Why?
True! Proteins determine an organisms traits more than anything else
A specific form of a gene that provides instructions for making a particular protein molecule.
gene version
What determines the function of a protein molecule?
Its structure and how it connects to other protein molecules
Both parents are heterozygous for silk flexibility (F1F2). What are the possible gene combinations for their offspring?
F1F1, F1F2, F2F2
True or false: Even if two organisms have the same proteins for a trait, if they are raised in different environments then that trait will be different for both organisms.
Why?
False. An organism's proteins determine its traits much more than the environment it's raised in.
A change that occurs to an organisms genes
Mutation
Why do siblings and parents differ from each other?
Offspring inherit different combinations of gene versions from parents
Two spider parents with medium silk flexibility have offspring. One of their offspring has very flexible silk, and one has low flexibility silk. How did the offspring end up with traits that are different from the traits of their parents?
They inherited different combinations of genes. Both parents were heterozygous (F1F2), and each child was homozygous with a different gene version (F1F1 and F2F2).
True or false: Genes connect to each other to control traits.
Why?
False. Genes are instructions for proteins, and proteins connect to each other to control traits.