Key Concepts:
- The study of life reveals unifying themes
- Evolution accounts for the diversity and unity of life
- Scientists form and test hypotheses to study nature
- Science benefits from a cooperative approach and diverse viewpoints
Biology is a subject of enormous scope
- Biology is the scientific study of life
- We recognize life by what living things do
Five Unifying Themes in Biology
- Organization
- Information
- Energy and matter
- Interactions
- Evolution
New Properties Emerge with Successive Levels of Biological Organization
- Life can be studied at different levels of complexity
- Enormous range can be divided into different levels of biological organization
- Reductionism - the approach that reduces complex systems into more simple
components
- Simpler components are more manageable to study
Emergent Properties
- Emergent properties result from arrangement and interaction of parts as complexity
increases
- Emergent properties characterize non biological entities
- Functioning machine only emerges when all necessary parts connect in the
correct way
- Systems biology analyzes interactions among parts of the biological system
- Used to study life at all levels
Structure and Function
- Each level of biological hierarchy correlates structure and function
- Analyzing biological structure gives clues to physiology
- Analyzing function gives clues to structure and organization
The Cell
- The cell is the smallest unit of organization that performs all functions necessary for life
- Cell Theory - all living organisms are made up of cells
- Every cell enclosed in membrane which regulates material transport between
extracellular and intracellular environment
Eukaryotes vs. Prokaryotes
, - Eukaryotic cell - a cell which contains membrane bound organelles, the largest of which
is usually the nucleus
- Prokaryotic cell - a cell which does not contain membrane bound organelles
- Simpler and usually smaller
- Does not contain a nucleus
Using Genetic Information
- Chromosomes contain DNA (deoxyribonucleic acid)
- Each chromosome contains one DNA molecule with thousands of genes
- Genes are units of inheritance
- Encode information for molecule synthesis by the cell
- Direct the development of the organism
DNA Structure
- DNA is composed of two long chains arranged in a double helix
- Each chain is made up of adenine, guanine, cytosine, and thymine nucleotides;
abbreviations: A, G, C, and T
- Sequence of nucleotides provides code for gene expression
- Gene Expression - process of converting information from gene into cellular
product
- DNA is transcribed into RNA, which is then translated into proteins
Genomics
- Genomics - study of whole sets of genes in one or more species
- Genome - entire library of genetic instructions found in an organism
- Proteomics - study of whole sets of proteins and their functions
- Proteome - entire set of proteins expressed by a cell, tissue, or organ
Bioinformatics - uses computational tools to process large volumes of data derived from
genomic study
Life-Giving Energy
- The sun is the main source of energy for life on Earth
- Transformation of this input of energy from one form to another enables life
- Chemical energy generated by photosynthetic organisms (producers) is taken by
organisms that feed on them (consumers)
- Using energy to perform works results in some loss to environment in the form of heat
Feedback Regulation
- Feedback Regulation - output (product) of a process regulates entire mechanism
- Biological processes self regulate through feedback mechanisms
- Negative Feedback - output of the system reduces the initial stimulus
- Positive Feedback - output of the system enhances stimulation of the system
Ecosystems
- The study of life reveals unifying themes
- Evolution accounts for the diversity and unity of life
- Scientists form and test hypotheses to study nature
- Science benefits from a cooperative approach and diverse viewpoints
Biology is a subject of enormous scope
- Biology is the scientific study of life
- We recognize life by what living things do
Five Unifying Themes in Biology
- Organization
- Information
- Energy and matter
- Interactions
- Evolution
New Properties Emerge with Successive Levels of Biological Organization
- Life can be studied at different levels of complexity
- Enormous range can be divided into different levels of biological organization
- Reductionism - the approach that reduces complex systems into more simple
components
- Simpler components are more manageable to study
Emergent Properties
- Emergent properties result from arrangement and interaction of parts as complexity
increases
- Emergent properties characterize non biological entities
- Functioning machine only emerges when all necessary parts connect in the
correct way
- Systems biology analyzes interactions among parts of the biological system
- Used to study life at all levels
Structure and Function
- Each level of biological hierarchy correlates structure and function
- Analyzing biological structure gives clues to physiology
- Analyzing function gives clues to structure and organization
The Cell
- The cell is the smallest unit of organization that performs all functions necessary for life
- Cell Theory - all living organisms are made up of cells
- Every cell enclosed in membrane which regulates material transport between
extracellular and intracellular environment
Eukaryotes vs. Prokaryotes
, - Eukaryotic cell - a cell which contains membrane bound organelles, the largest of which
is usually the nucleus
- Prokaryotic cell - a cell which does not contain membrane bound organelles
- Simpler and usually smaller
- Does not contain a nucleus
Using Genetic Information
- Chromosomes contain DNA (deoxyribonucleic acid)
- Each chromosome contains one DNA molecule with thousands of genes
- Genes are units of inheritance
- Encode information for molecule synthesis by the cell
- Direct the development of the organism
DNA Structure
- DNA is composed of two long chains arranged in a double helix
- Each chain is made up of adenine, guanine, cytosine, and thymine nucleotides;
abbreviations: A, G, C, and T
- Sequence of nucleotides provides code for gene expression
- Gene Expression - process of converting information from gene into cellular
product
- DNA is transcribed into RNA, which is then translated into proteins
Genomics
- Genomics - study of whole sets of genes in one or more species
- Genome - entire library of genetic instructions found in an organism
- Proteomics - study of whole sets of proteins and their functions
- Proteome - entire set of proteins expressed by a cell, tissue, or organ
Bioinformatics - uses computational tools to process large volumes of data derived from
genomic study
Life-Giving Energy
- The sun is the main source of energy for life on Earth
- Transformation of this input of energy from one form to another enables life
- Chemical energy generated by photosynthetic organisms (producers) is taken by
organisms that feed on them (consumers)
- Using energy to perform works results in some loss to environment in the form of heat
Feedback Regulation
- Feedback Regulation - output (product) of a process regulates entire mechanism
- Biological processes self regulate through feedback mechanisms
- Negative Feedback - output of the system reduces the initial stimulus
- Positive Feedback - output of the system enhances stimulation of the system
Ecosystems
