BIO 201 CHAPTER 1
An organism’s adaptations to its environment
- For example, the color of the beach mouse has come to be well matched, or adapted, to its local background
- Evolution is the process of change that has transformed life on Earth
Biology is a subject of enormous scope
There are five unifying themes
Energy and Matter
What is a cell?
An Organism’s Basic Unit of Structure and Function
The cell is the smallest unit of organization that can perform
all activities required for life
Every cell is enclosed by a membrane that regulates passage of materials between the cell and its environment
The cells of bacteria and archaea are prokaryotic, while all other forms of life are composed of eukaryotic cells
Has membrane-enclosed organelles, the largest of which is usually the nucleus
Simpler and usually smaller and does not contain a nucleus or other membrane-enclosed organelles
Within cells, structures called chromosomes contain genetic material in the form of DNA (deoxyribonucleic acid)
Each chromosome contains one long DNA molecule with hundreds or
thousands of genes
The units of inheritance.
They encode information for building the molecules synthesized
within the cell
The genetic information encoded by DNA directs the development of an organism
Each DNA molecule is made up of ?
Two long chains arranged in a double helix
Each chain (DNA) is made up of ?
Four kinds of chemical building blocks called nucleotides and abbreviated A, G, C, and T
For many genes, the sequence provides the blueprint for making ?
- DNA is transcribed into RNA, which is then translated into a protein
The process of converting information from gene to cellular product