Mostly Genes, Alleles and Traits Vocab
The scientific study of biological inheritance is called ________.
What is genetics?
Organisms that have two identical alleles for a particular gene (such as BB or bb for example) are __________.
What is homozygous?
Many genes exist in several different forms (more than two alleles per trait) and are therefore said to have ________________.
What are multiple alleles?
What is the difference between dominant and recessive alleles? How do we represent this difference using letters?
Dominant alleles will be expressed over recessive ones in cases of simple dominance... Uppercase letters represent dominant alleles, lowercase letters represent recessive alleles
What stage is the cell in before Meiosis even begins? What does the cell do during this stage right before Meiosis starts to prepare?
Interphase, the cell Increases its chromosomes from 46 to 92
A _____ is a specific inherited characteristic, like hair color or eye color.
What is a trait?
Organisms that have two different alleles for the same gene (such as Bb for example) are ____________.
What is heterozygous?
Traits controlled by two or more genes are said to be ________________.
What is polygenic?
Draw a punnet square to represent the cross between a plant with a heterozygous genotype and a short plant. Use a Punnett Square to identify the probability of an offspring that is short.
Can't draw a punnet square on this thing but there should be a 50% chance the offspring is short
What steps make up Meiosis 1? Briefly describe what happens in each step
Prophase 1 - homologous chromosomes Pair up & crossing over occurs
Metaphase 1 - homologous chromosomes line up in the Middle of the cell
Anaphase 1 - homologous chromosomes are pulled Apart to opposite ends of the cell
Telophase 1 - Both groups of separated chromosomes are Trapped in different nuclear envelopes
_____ are factors that determine an individual’s characteristics and are passed from one generation to the next.
What are genes?
_________ describes an organism’s physical traits (ex. Brown hair)
What is phenotype?
The _______ cells of most adult organisms contain two complete sets of inherited chromosomes and two complete sets of genes.
What is diploid?
Petal color in roses is an example of incomplete dominance. Draw a Punnet square to show the results of a cross between two pink roses and predict the petal colors of their offspring.
I can't draw a punnet square on this thing but 25% of the offspring should have red petals, 50% of the offspring should have pink petals and 25% of the offspring should have white petals
What happens during cytokineses immediately after Meiosis 1? How many cells are present and how many chromosomes does each cell have at this point in the process?
Cytokineses (immediately following Meiosis 1) - The cell is Cut in two, producing two (diploid) cells with 46 chromosomes each
The different forms of a single gene are called _______.
What are alleles?
________ describes an organism’s genetic makeup (ex. BB)
What is genotype?
_______ cells have a single set of chromosomes and genes such as the gametes of sexually reproducing organisms.
What is haploid?
Feather color in chickens is an example of codominance. Assuming that black feathers are dominant over white feathers, draw a Punnet square to show the results of a cross between a white feathered chicken and a black feathered chicken.
I can't draw a Punnet square on this thing but 100% of the offspring should be black and white speckled
What steps make up Meiosis 2? Briefly describe what happens in each step
Prophase 2 - homologous chromosomes Pair up
Metaphase 2 - homologous chromosomes line up in the Middle of the cell
Anaphase 2 - chromatids are pulled Apart to opposite ends of the cell
Telophase 2 - Both groups of separated chromatids are Trapped in different nuclear envelopes
In ____________________, the heterozygous phenotype lies somewhere between the two homozygous phenotypes (A red flower is crossed with a white flower to produce a pink flower).
What is incomplete dominance?
___________ is a situation in which the phenotypes produced by both alleles are clearly expressed (A white chicken crossed with a black chicken produces white and black, speckled offspring)
What is co-dominance?
_____________ is a process that occurs during prophase 1 in which bits and pieces of homologous chromosomes are exchanged.
What is crossing over?
We learned that some genes tend to be inherited together, such as red hair and freckles. Why does this occur?
This occurs due to a concept called gene linkage which states that the closer to genes are located on the same chromosome, the more likely they'll be inherited together
What happens during cytokineses immediately after Meiosis 2? How many cells are present and how many chromosomes does each cell have at the end of whole process of Meiosis?
Cytokineses (immediately after Meiosis 2) - Both cells are Cut in two, producing four (haploid) cells with 23 chromosomes each