What is Codominance?

What is Codominance?

Codominance Occurs when both alleles for a gene are expressed in a heterozygous individual. Roan Cattle

Codominance There are two alleles for coat color in cattle. Yet, there are three phenotypes: A combination of red and white hairs!

Codominance Since both alleles are DOMINANT, a capital letter is used for both alleles! WW RR WR

Let s do some Monohybrid Crosses! Cross a RED cow with a WHITE bull X

Codominance Cross a Roan cow with a Roan bull X

Let s Think A cross between a black cat & a tan cat produces a tabby pattern (black & tan fur together). a) What pattern of inheritence does this illustrate? Codominance, two phenotypes together at the same time. b) What percent of kittens would have tan fur if a tabby cat is crossed with a black cat?

What are Multiple Alleles? Traits controlled by 3 or more alleles of the same gene that code for a single trait. ABO Blood Types

Blood Type contains three alleles: Genotype I A I A I A i I B I B I B i I A I B ii Blood Type A A B B AB O I A,I B, i

Here is another example of Codominance: Both the I A allele and the I B allele are expressed!

Let s Try some Blood Typing Crosses!!! A husband and wife have the ABO blood group genotypes IAIB and ii. What ABO blood types can their children have?

Let s Try some Blood Typing Crosses!!! A husband and wife have the ABO blood groups I B i and I A i. What ABO blood types can their children have?

What is blood made up of? An adult human has about 4 6 liters of blood circulating in the body. Among other things, blood transports oxygen to various parts of the body. Blood consists of several types of cells floating around in a fluid called plasma. The red blood cells contain hemoglobin, a protein that binds oxygen. Red blood cells transport oxygen to, and remove carbon dioxide from, the body tissues. The white blood cells fight infection. The platelets help the blood to clot, if you get a wound for example. The plasma contains salts and various kinds of proteins.

BLOOD FACT In the United States, a blood transfusion is needed about every two seconds.

DID YOU KNOW? When someone donates a pint of blood, that blood is separated into red cells, plasma and platelets. Each one of these can be given to a different patient who needs only that part of the blood.

BLOOD TYPE Not everyone has the same blood type! Blood type refers to features of the person s red blood cells.

So what s the deal with Blood Transfusions?

Located on the surface of red blood cells!

Located in the plasma

Blood Transfusions A blood transfusion is a procedure in which blood is given to a patient through an intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if a person s body can't make blood properly because of an illness. Who can give you blood? Universal Donor People with TYPE O blood are called Universal Donors, because they can give blood to any blood type. People with TYPE AB blood are called Universal Recipients, because they can receive any blood type. Rh + Can receive + or - Rh - Can only receive - Universal Recipient

Rh Factors Scientists sometimes study Rhesus monkeys to learn more about the human anatomy because there are certain similarities between the two species. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein. The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor. If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-). A+ A- B+ B- AB+ AB- O+ O- http://www.fi.edu/biosci/blood/rh.html

How common is your blood type?