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Genetics is the study of how living things pass on characteristics (or traits) from one generation to the next.

Genetics syllabus

I.  Gregor Mendel and origin of genetics

II. Human phenotypes that show Mendelian inheritance

III. Punnett Squares. How likely is it that a trait will be inherited?

IV. Punnet squares Monohybrid, Dihybrid, and Trihybrid Crosses

V.  Chromosomes in cells

VI. Meiosis: Creation of sperm or egg cells.

VII. DNA bases, nucleotides, and how they wind into a helix.

VIII. Analogies: DNA is like an alphabet, a word, a sentence or a book.

IX. DNA replication

X. DNA transcription (make mRNA copy of the DNA)

XI. DNA translation and the genetic code: mRNA into protein

XII. Mutations (errors)

XIII. Genetic engineering

XIV. Genetic diseases

Genes and Mutations Super Human Project


Related topics

A. Non-mendelian inheritance.

B. How do we know what DNA looks like


Genetics Apps

How big is a chromosome, compared to a cell?  Cell size and scale app. Univ of Utah Genetic Science Learning Center)

StarGenetics allows students to simulate mating experiments between organisms that are genetically different across a range of traits.

StarGenetics is a Mendelian genetics cross simulator

VGL simulates genetics research.  Cross hypothetical creatures and examine the progeny in order to determine the mechanism of inheritance of a particular trait. 

The Virtual Genetics Lab (VGLII)

Pigeon Breeding: Genetics At Work

Pigeon Breeding. University of Utah, Genetic Science Learning Center


Sample questions

Feb 2016 MCAS.  The stored information in DNA codes for which of the following?
A. proteins
B. simple sugars
C. mitochondria when energy is needed
D. large vacuoles when nutrients are abundant


Feb 2016 MCAS. A type of golden brown coat color in horses is called palomino. Several pairs of palomino horses are mated. The results of the crosses are here:

Coat Color – Percent of Offspring
palomino 50%          reddish-brown 25%      creamy white 25%


Feb 2016 MCAS. Which of the following is the most likely inheritance pattern of coat color in horses?
A. complete dominance
B. incomplete dominance
C. polygenic inheritance
D. sex-linked inheritance


Which of the following statements explains the importance of enzymes that check for and repair mistakes during DNA replication?

A. The enzymes replace the DNA with RNA.
B. The enzymes speed up the rate of RNA synthesis.
C. The enzymes remove many recessive gene copies from the nucleus.
D. The enzymes prevent many genetic mutations from being expressed.


Feb 2016 MCAS. (42) Four boys have the same biological mother and father. What percentage of each boy’s chromosomes come from the mother?
A. 0% .      B. 25% .      C. 50% .     D. 100%


Feb 2017 MCAS.  A red-eyed male fruit fly is crossed with a heterozygous red-eyed female fruit fly. The expected results for the cross are shown in the table below.

Phenotype fruit fly
Which of the following describes this inheritance pattern and the allele that codes for red eye color in fruit flies?

A. The inheritance pattern is sex-linked, and the allele for red eye color is dominant.
B. The inheritance pattern is sex-linked, and the allele for red eye color is recessive.
C. The inheritance pattern is codominant, and the allele for red eye color masks the allele for white eye color.
D. The inheritance pattern is codominant, and the alleles for red eye color and
white eye color are expressed equally


The diagram below represents a biological process involving DNA.

What process is represented?
A. fertilization .      B. mutation .      C. replication .    D. translation


Feb 2017.  The bacterium E. coli is a model organism used by many scientists for genetic and biochemical research. Which of the following statements helps explain why E. coli is so frequently used for research?

A. It has a large nucleus and a long generation time.
B. It has hundreds of chromosomes and a long lifespan.
C. It has a simple cell structure and reproduces rapidly.
D. It has many kinds of organelles and reproduces sexually.

Learning Standards

HS-LS1-1. Construct a model of transcription and translation to explain the roles of DNA and RNA that code for proteins that regulate and carry out essential functions of life.

Clarification Statements: Proteins that regulate and carry out essential functions of life include enzymes (which speed up chemical reactions), structural proteins (which provide structure and enable movement), and hormones and receptors (which send and receive signals). The model should show the double-stranded structure of DNA, including genes as part of DNA’s transcribed strand, with complementary bases on the nontranscribed strand.

State Assessment Boundaries: Specific names of proteins or specific steps of transcription and translation are not expected in state assessment. Cell structures included in transcription and translation will be limited to nucleus, nuclear membrane, and ribosomes for state assessment.

HS-LS3-1. Develop and use a model to show how DNA in the form of chromosomes is passed from parents to offspring through the processes of meiosis and fertilization in sexual reproduction.

Clarification Statement: The model should demonstrate that an individual’s characteristics (phenotype) result, in part, from interactions among the various proteins expressed by one’s genes (genotype)

State Assessment Boundary: Identification of specific phases of meiosis or the biochemical mechanisms involved are not expected in state assessment.

HS-LS3-2. Make and defend a claim based on evidence that genetic variations (alleles) may result from (a) new genetic combinations via the processes of crossing over and random segregation of chromosomes during meiosis, (b) mutations that occur during replication, and/or (c) mutations caused by environmental factors. Recognize that mutations that occur in gametes can be passed to offspring.

Clarification Statement: Examples of evidence of genetic variation can include the work of McClintock in crossing over of maize chromosomes and the development of cancer due to DNA replication errors and UV ray exposure.

State Assessment Boundary: Specific phases of meiosis or identification of specific types of mutations are not expected in state assessment.

HS-LS3-3. Apply concepts of probability to represent possible genotype and phenotype combinations in offspring caused by different types of Mendelian inheritance patterns.

Clarification Statements: Representations can include Punnett squares, diagrams, pedigree charts, and simulations. Inheritance patterns include dominant-recessive, codominance, incomplete dominance, and sex-linked.

HS-LS3-4(MA). Use scientific information to illustrate that many traits of individuals, and the presence of specific alleles in a population, are due to interactions of genetic factors
and environmental factors.

Clarification Statements: Examples of genetic factors include the presence of multiple alleles for one gene and multiple genes influencing a trait.
An example of the role of the environment in expressed traits in an individual can include the likelihood of developing inherited diseases (e.g., heart disease, cancer) in relation to exposure to environmental toxins and lifestyle; an example in populations can include the maintenance of the allele for sickle-cell anemia in high frequency in malaria-affected regions because it confers partial resistance to malaria.

State Assessment Boundary: Hardy-Weinberg calculations are not expected in state assessment.

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