Biology is the study of living things

7 Characteristics or Properties of Life:
1.
2.
Cellular Structure and Function
Reproduction
3.
4.
5.
6.
7.
Metabolism
Homeostasis
Heredity
Evolution
Interdependence
Life is characterized by the presence of all these properties at some stage in an organism’s life, not just by one or two.

•
1.
Structure and Function
• All living things are made of one or more cells.
• Cells are highly organized, tiny structure with thin coverings called membranes.
• Some organisms have only a single cell, while others are multicellular.
Myeloma Cells

• A Cell is the smallest unit capable of all life functions.
• Unicellular - organism composed of one cell. Uni=1
• Multicellular - organism that is composed of many specialized cells, each having a unique role in the function of the organism multi=many
In multicellular organisms cells are organized into tissues, tissues are organized into organs, organs are organized into systems, and organ systems work together to make the organism.

• simplest most complex
• Cells tissue organs organ system organism
• EX:
• Muscle muscle stomach digestive human
• cell tissue system squirrel
When group of cells function together to perform an activity, they form a tissue . Groups of two or more tissues that function together make up organs . An organ system is a group of organs that work together to carry out major life functions. Organ systems work together to form the multicellular organism

• 2.
It is the process by which organisms make more of their own kind from one generation to the next. Reproduction is not essential for the survival of an individual organism.
It is essential for the continuity of life, because no organism lives forever. If members of a group of living things fail to reproduce, they become extinct.

• 2 Types of Reproduction:
• 1) Asexual: single parent gives ride to one or more individuals.
examples: budding, binary fission, spore formation
• 2) Sexual: The joining of two specialized sex cells, usually from different parents.
Sexual
Asexual

• 3.
• It is the sum of all the chemical reactions carried out in an organism.
Living organisms perform many different chemical reactions in order to obtain and use energy to run and to process information.
• All living things use energy to grow, to move, and to process information.
Without energy life soon stops.

Energy flow
Starts with the sun
Plants, algae, bacteria capture this solar energy and use it to make complex molecules by photosynthesis.
Plant-eating organisms
Meat-eating organisms

Autotrophs -organisms that make their own food. Example: Plant
Heterotrophs -organisms that gain energy by eating other organisms.
Some unicellular organisms, as well as all animals, and fungi, are heterotrophs.

• 4.
• The maintenance of stable internal conditions in spite of changes in the external environment.
• Example in humans—breathing rate, heart rate, blood pressure returning to “normal” after exercise. “Normal” homeostasis for human blood pressure is usually 120/80 mm of mercury

• 5.
• The passing of traits from parent to offspring .
• All living things are able to pass their characteristics (traits) to their offspring through genes. Genes are sets of inherited instructions for making proteins. Genes control when proteins are made and what proteins are made.
These instructions, which are coded in a molecule called deoxyribonucleic acid
(DNA), determine an organism’s traits.

• Sometimes damages causes genes to change. A change in the DNA of a gene is called a mutation .
.
• Most mutations are harmful, but sometimes mutations can help an organism survive.
– Example: In humans, a genetic mutation for the blood protein hemoglobin, which carries oxygen to the body’s cells.
– Harmful effect—results in sickle cell anemia, which impairs the oxygen-carrying capability of the cell
– Positive effect—the mutation produces resistance to malaria.

6.
• Is is a change in inherited traits of species over time.
• A species is a group of genetically similar organisms, that can produce fertile offspring.
• Natural selectionDarwin called the process in which organisms with favorable genes are more likely to survive and reproduce.

7.
• It is when organisms in a biological community have evolved to live and interact with other organisms. A biological community is a group of interacting organisms.
• Ecology is the science that studies the interactions of living organisms with one another and with the nonliving part of their environment.