Living Environment Translated English 2014 | Page 22

9. Genotype- the genetic makeup of an organism
10.Phenotype-the physical appearance and behavior of an
organism as a result of its genotype
11. Dominant- describe a trait that covers over another form of that
trait; always shows up if present
12.Recessive- describes a trait that will only show up if there are no
dominant alleles present
13.Incomplete dominance-produces a phenotype that is a blend
between two traits because both traits are equal in strength
14.Sex-linked trait- a trait that shows up more often in one sex
than it does in the other
15.Sex-limited trait- a trait that only shows up in one sex or the
other
16.Mutation- a change in the nitrogen bases in DNA
17. Polygenic inheritance- a trait that is produced by two or more
genes
18. Genetic engineering-the process of changing an organism’s DNA
to give the organism new traits
19.Recombinant DNA- genetically engineered DNA that contains
genes from more than one organism
20.Gene therapy-a procedure used to treat a disease in which a
defective or missing gene is replaced or a new gene is inserted
3. General Notes:
 Heredity is the passing of traits from parent to offspring.
 Genetics is the study of how traits are inherited through the
interactions of alleles
 Gregor Mendel is known as the “ Father of Genetics”- he worked
with pea plants and showed patterns of inheritance
 Mendel used the word “ trait” to describe characteristics that can be
inherited ( ex: eye color, leaf shape)
 Mendel’s first law is called the Law of Segregation.