Biology

Chapter 1

Themes in Biology

Concepts/Ideas/Facts:

  1. first living things were single cell organisms
  2. most cells in a multicellular organism are specialized to perform one or just a few functions.  Cells of multicellular organisms depend on other specialized cells for their own survival.

Definitions:

  1.  Biology – the science of life
  2.  Organism – any living thing
  3.  Natural Selection – organism that have certain inheritable traits are better able to survive in specific environments that organisms that lack those traits
  4.  Adaptations – favorable traits
  5.  Phylogeny – the evolutionary history of groups of organisms
  6.  Inheritance –the acquisition of traits from parents
  7.  Asexual Reproduction – the production o offspring that does not involve the union of gametes.
  8.  Sexual Reproduction – the production of offspring from the combination of genetic    material.  Union of female (egg) and male (sperm) gametes.
  9.  Zygote – the product of the union (fusion) of egg and sperm
  10.  Gene Expression – when a gene is active
  11.  Morphology – study of the form and structure of an organism
  12.  Anatomy – the study of the internal structure of an organism
  13.  Autotroph – organisms that acquire energy by making there own food
  14.  Heterotrophs – organism that gain energy by eating other organisms
  15.  Ethics – the study of what is right and wrong and of moral choices.
  16.  Levels of Organization – atoms, molecules, cells, tissue, organs, organ systems, organisms.
  17.  Response – reaction to a stimulus
  18.  Behavior – a complex set of responses
  19.  Cell Division – orderly formation of new cells from a parent cell
  20.  Cell Enlargement – increase in cell size
  21.  First Law of Thermodynamics – energy can be neither created nor destroyed during a process,  only the form of energy can be changed.

Seven Themes of Biology:

  1. Evolution – theory that species change over time by a process of natural selection
  2. Reproduction and Inheritance – all organisms come from preexisting organisms by the process of reproduction.  Genetic information is transferred from parent to offspring via DNA.  The acquisition of traits from parents is called inheritance.
  3. Development – the process by which a zygote becomes a mature individual.  This individual can be a one-cell organism (unicellular organism), or a multi-cellular organism.
  4. Structure and Function – the structure of an organism is the physical construction of that organism while the function constitutes how that structure is used.  Form follows function.
  5. Energy Relationships – how an organism gets, converts, uses, stores, and transfers energy.  All organisms use energy for growth and maintenance, and for carrying out essential life functions.
  6. Ecology – the study of the interactions of organism with each other and the environment.  It recognizes the interdependence of all organisms with each other and the physical environment.  The stability of the environment depends on the healthy functioning of organisms in the environment.
  7. Science and Society – the application of science to solve specific problems facing society as well as to improve human life.  Decisions involve the use of ethics.  Bioethics is the application of ethics to biological concerns.  Such concerns as genetic engineering, global warming, and other issues involves ethical decision-making.

Characteristics of Life:

  1. Cells – all living things are made of cells
  2. Organization – all organisms are organized at both the molecular and cellular levels.  They take in substances from the environment and organize then into complex ways.  Cells have specific structures that carry out particular functions.  In multi-cellular organisms cells are organized into tissue, which are organized into organs, which are organized into organ system, which are organized into organisms.
  3. Energy Use – all organisms need energy for growth and maintenance
  4. Response to the Environment (stimuli)– all organisms respond to the environment (stimulus).
  5. Growth – organisms grow through cell division and enlargement in an orderly fashion.  In multi-cellular organisms cell division and cell enlargement together result in growth.
  6. Reproduction – essential for the continuation of the species but it is not essential for the survival of an individual organism.
  7. Adaptation – an inherited trait that increases an organism’s chances for survival in a particular environment.  Variations of adaptation are essential for the continuation of life as they confer an advantage to some members of a species in an ever changing environment.

Cell Organization:

      1.   TISSUE – groups of cells that carry out specific functions

a.       epithelial cells – sheets of closely packed cells that form surface coverings (skin)

b.      connective tissue – loosely scatted cells that support, bind together, or protect other tissue or organs.  Ligaments and tendons are connective tissue.

c.       muscle tissue – cells that pull against one another by contraction

d.      nerve tissue – cells specialized for transmitting messages from one part of the body to another

2.   ORGAN – several types of tissue that interact or work together to perform  specific functions.

a.       stomach – made up of muscle tissue, epithelial tissue, connective tissue, and nerve tissue.

  1. ORGAN SYSTEM – groups of organs that work together to perform a set of related tasks or functions.                                                                                   

  1. digestive system – system of various organs such as the mouth, esophagus, stomach, intestines, and other organs that digest food and bring nutrients to the organisms. 

  2. respiratory system – primary function is to bring oxygen to the cells.  Made up of the mouth, nose, trachea, larynx, lungs, diaphragm, and other organs.

  3. circulatory system – heart, lungs, blood vessels

4.  COLONIAL ORGANIZATIONS – a collection of genetically identical cells that live together in a closely connected group.  Some of the cells perform specialized functions that benefit the entire colony although they are the same as the other cells. These colonial organizations are considered to be intermediate evolutionarily between prokaryotes are eukaryotes. 

  1. digestive system – system of various organs such as the mouth, esophagus, stomach, intestines, and other organs that digest food and bring nutrients to the organisms. 

  2. respiratory system – primary function is to bring oxygen to the cells.  Made up of the mouth, nose, trachea, larynx, lungs, diaphragm, and other organs.

  3. circulatory system – heart, lungs, blood vessels