Living Environment Translated English 2014 | Page 25
o XX- female
o XY- male
An allele inherited on a sex chromosome is called a sex-linked gene.
o Sex-linked traits show up more often in one sex ( usually
males) than they do in the other sex.
o Examples: colorblindness; hemophilia
A sex-limited trait is found on the sex chromosome and ONLY shows
up in one sex or the other.
Recessive genes control many human genetic disorders.
Pedigrees are visual tools used to trace a trait through several
generations of a family.
Genetic Engineering - the process of changing an organism’s DNA to
give the organism new traits.
o Scientists work with biological and chemical methods to
change the arrangement of DNA that make up a gene.
o One method of genetic engineering is making recombinant
DNA. This is a method of inserting form one organism into
another organism. Usually the receiving organism is bacteria.
o Bacteria are used because of their rapid reproduction rates.
Unit 6: Ecology
A. Vocabulary
1. Ecology- the study of the interactions that take place among
organisms and their environment
2. Biosphere- part of the Earth that supports life, including the top
portion of the Earth’s crust, the atmosphere, and all of the water on
the Earth’s surface
3. Ecosystem- all of the living organisms that live in an area and the
nonliving features in their environment
4. Biome- large areas with similar climates and ecosystems