TraitsDog Chromosome

Journal Question

18 Dec 2012

Describe the relationship between: DNA Chromosomes Genes, and Traits

DOG DNA

You will assigned a partner.

You will need: 1 paper bag with 8 gene strips Tape Construction paper Markers Trait Map

Background Every organism inherits a unique

combination of traits.

DNA is a set of instructions that specifies the traits of an organism.

Information in the DNA molecule is divided into segments (called genes).

Variations in the DNA lead to the inheritance of different traits.

Determine the first trait of your dog (body shape) by randomly picking a piece of dog DNA out of the envelope.

Look at the symbols on the DNA strip you have chosen. Match the pattern to one you see on the Dog Traits Key for body shape.

Write this genotype on the back of your construction paper.

Select the next strip. This strip will be for the head shape. Record the genotype on the back of the construction paper. Tape this strip to the end of the first strip.

Repeat these steps for each of the 8 traits listed on the Dog Traits Key.

Ultimately, you will have one long strip of dog DNA. This will become the DNA recipe for your entire dog.

When you have finished, draw your dog with all of its on the front of the construction paper.

Finishing Touches Name your dog and put your names

on the back.

If your dog is a male, tape the long DNA strip to the left hand side of your dog’s picture.

If your dog is a female, tape the long DNA strip to the right side of your dog’s picture.

Discussion A set of instructions called DNA makes

a “recipe” for traits in all organisms.

Information in a DNA strand is grouped into small segments. Each segment is made of even smaller units (like recipes are made of words, and words are made of letters).

Differences in the DNA “alphabet” are what make differences in traits (just like a different sequence of letters makes different words, and a different recipe).

Journal Question 19 Dec 2012

With only 8 traits and 4 possible alleles, why do all of your dogs look different from each other?

Reflection on the activity What did you like, not like? What did you learn? What will happen when these dogs

are mated?

Journal Question 03 Jan 2013

How are genes and traits related?

Discussion The DNA molecule contains a sequence of four

chemical bases (represented here by four symbols). Each base is referred to by the first letter of its name: Adenine (A), Cytosine (C), Guanine (G) and Thymine (T).

The sequence of these chemical bases encodes a detailed set of instructions for building an organism’s traits. (The human genome contains approximately 3 billion pairs or bases!)

Each one of you assembled the DNA strips in the order they were drawn. This is because all individuals of a species have the same genes in the same order along their chromosomes. (This is what allows researchers to “map” the location of a gene to a specific place on a chromosome.)

Discussion It is the small sequence variations within each

gene that lead to differences in traits. There is usually a limited number of sequence variations for a gene. That is, a gene usually comes in a few different forms or flavors, called “alleles”.

There was a possibility of four different alleles for each of the dog genes in this activity.

In this activity, a single gene determined each dog trait. More often a trait is influenced by more than one gene as well as environmental factors.

Human Genome Project http://www.ornl.gov/sci/techresources/Human_Geno

me/posters/chromosome/chooser.shtml

Canine Genome Dogs have 78 chromosomes or ( ) pairs.

Just like for the human genome, knowing which genes are linked with certain diseases or characteristics help breeders mate for healthier dogs.

During Meiosis

Body Shape

Head Shape

Ears

Legs

Eye Color

Tail Shape

Coat Color

Hair Type

Male DNA

Female DNA

Dog DNA Part 2 Pair up a female and male dog.

Blue is always dominant. Green is always recessive. Yellow is second recessive. Pink is second dominant.

Draw your new dog and list its traits.

Repeat with a new mate. Use the same sheet of paper, front and back.

Pick one Look over the list of traits and write a

short paragraph describing the ideal set of traits for your dog if it were: A herding dog A hunting and retrieving dog A tracking dog A companion dog for a disabled person

in a wheelchair A dog that kept small rodents out of

houses A racing dog