Answer:
True
Explanation:
Chiasma is the site of crossing over. It is an X-shaped site that appears in a tetrad (bivalent) chromosome during the diplotene stage of prophase I of meiosis I. Crossing over refers to the exchange of segments of chromatids and occurs between homologous chromosomes only. Crossing over is the event of prophase I of meiosis I and produce new gene combinations.
The homologous chromosomes are separated from each other but remain attached at chiasmata. The dissolution of chiasmata occurs by the end of prophase I and separates the homologous chromosomes completely from each other. Crossing over does not occur in mitosis. Since mitosis does not include crossing over, chiasmata are also not formed in mitosis.
Answer:
Type O
Expresses the B agglutinin
Expresses all the major antibodies
The most common US blood type
The universal donor
Type AB+
Expresses all of the major antigens
Expresses the D antigen
The least common US blood type
The universal acceptor
Expresses the Rh factor
Expresses A agglutinogen
Explanation:
Blood type is a grouping of blood into classes that have the presence or absence of antibodies and or antigens on the red blood cell surfaces
The class of blood determines whether the antigens are glycolipids, carbohydrates, proteins or glycoproteins of Type O
The blood type of a person is an inherited trait from both parental gene. There are various blood grouping system with the ABO and Rh systems being the most important as they determine the suitability of a given blood for transfusion.
