Exploring LIFE Biology The study of Life l

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Exploring LIFE Ø Biology – The study of Life l What does it mean

Exploring LIFE Ø Biology – The study of Life l What does it mean to be ALIVE? l How do you know if something is ALIVE?

Is Fire ALIVE?

Is Fire ALIVE?

All living things share basic properties Eight Characteristics of Life ü C Composed of

All living things share basic properties Eight Characteristics of Life ü C Composed of cells (+1) ü H Homeostasis ü A Adaptation ü R Reproduce ü R Respond to the environment ü G Growth & Development ü E Energy (metabolism) ü D DNA /RNA (genetic material)

 • Living organisms consist of organic (carbon-containing) molecules organized to form cells •

• Living organisms consist of organic (carbon-containing) molecules organized to form cells • Cells Life’s basic units of structure and function

Unicellular Organisms ü Entire organism is made up of one single cell ü Bacteria

Unicellular Organisms ü Entire organism is made up of one single cell ü Bacteria and protists

Multicellular Organisms ü The organism is made up of many cells ü Cells have

Multicellular Organisms ü The organism is made up of many cells ü Cells have specialized functions within the organism

Homeostasis = ability of an organism to maintain relatively constant, stable state of internal

Homeostasis = ability of an organism to maintain relatively constant, stable state of internal conditions EXAMPLES: ü Body temperature ü Blood volume ü p. H balance ü Water balance All organ systems contribute to homeostasis

Adaptation üA trait (or process) that enables organisms to become better suited to their

Adaptation üA trait (or process) that enables organisms to become better suited to their environment ü Species obtain adaptations through evolution, which occurs over great periods of time

Ø Gradual change in a species over time l l Species differ greatly in

Ø Gradual change in a species over time l l Species differ greatly in their adaptations to the many distinct environments on Earth Both the unity and diversity of organisms can be explained by the mechanisms of evolution and natural selection…. more on that later

An Example of Adaptation Desert plants have succulent waxy leaves and stems to store

An Example of Adaptation Desert plants have succulent waxy leaves and stems to store water and reduce water loss

Reproduction is the process of producing new organisms. Two types: Asexual Reproduction A single

Reproduction is the process of producing new organisms. Two types: Asexual Reproduction A single parent organism reproduces by itself üEx: binary fission in bacteria

Sexual Reproduction üTwo different parent organisms contribute genetic information üInvolves the combination of male

Sexual Reproduction üTwo different parent organisms contribute genetic information üInvolves the combination of male and female sex cells

Respond to the Environment Living things respond to the environment by reacting to a

Respond to the Environment Living things respond to the environment by reacting to a stimulus (a thing or event that produces a specific reaction)

Organisms react to stimuli: üLight üTemperature üOdor üSound üGravity üHeat üWater üPressure Example: A

Organisms react to stimuli: üLight üTemperature üOdor üSound üGravity üHeat üWater üPressure Example: A plant’s leaves and stems grow toward light

ALL ORGANISMS GROW & DEVELOP

ALL ORGANISMS GROW & DEVELOP

Growth means to get bigger in size

Growth means to get bigger in size

Development involves a change in the physical form or physiological make-up of an organism

Development involves a change in the physical form or physiological make-up of an organism

All living organisms obtain & use energy for all body processes: growth and development,

All living organisms obtain & use energy for all body processes: growth and development, damage repair, , transport, and reproduction

1. PRODUCERS: - Plants, algae, and other photosynthetic organisms that produce their own “food”

1. PRODUCERS: - Plants, algae, and other photosynthetic organisms that produce their own “food” for energy (from CO 2, H 2 O, & the sun) - Entire ecosystems depend on producers 2. CONSUMERS: - Organisms that obtain nutrients and energy from consuming the food made by producers

Metabolism All chemical reactions occurring within an organism ü Anabolism + Catabolism = Metabolism

Metabolism All chemical reactions occurring within an organism ü Anabolism + Catabolism = Metabolism

Anabolism Process of building up complex substances from simpler substances ü Building up cells

Anabolism Process of building up complex substances from simpler substances ü Building up cells and cellular components ü Photosynthesis

Catabolism Process of breaking down complex substances into simpler substances to release energy ü

Catabolism Process of breaking down complex substances into simpler substances to release energy ü Digestion ü Cellular Respiration

Genes carry hereditary information Genes are composed of DNA Heredity is the reason offspring

Genes carry hereditary information Genes are composed of DNA Heredity is the reason offspring resemble their parents Mutations change DNA code and can be passed from generation to generation

Characteristics of Life - RECAP ü C Composed of cells (+1) ü H Homeostasis

Characteristics of Life - RECAP ü C Composed of cells (+1) ü H Homeostasis ü A Adaptation ü R Reproduce ü R Respond to the environment ü G Growth & Development ü E Energy (metabolism) ü D DNA /RNA (genetic material)

Organisms Viruses Metabolism Do not metabolize Grow and Develop No Growth and Development Sexual

Organisms Viruses Metabolism Do not metabolize Grow and Develop No Growth and Development Sexual or Asexual Reproduction Must use the machinery of cells to reproduce Composed of cells DNA or RNA and a protein coat – no cells Maintains Homeostasis Does not maintain Homeostasis

STRUCTURE OF A VIRUS DNA or RNA CAPSID (protein coat)

STRUCTURE OF A VIRUS DNA or RNA CAPSID (protein coat)

How is life classified? Ø Taxonomy = biological classification • • binomial nomenclature Two-word

How is life classified? Ø Taxonomy = biological classification • • binomial nomenclature Two-word “scientific” name (Genus & species)

Benefits of Classifying Accurately & uniformly names organisms • Prevents misnomers such as “starfish”

Benefits of Classifying Accurately & uniformly names organisms • Prevents misnomers such as “starfish” & “jellyfish” that aren't really fish • Uses same language (Latin or some Greek) for all names • Sea”horse”? ? 31

Prokaryotes – The first Cells Ø Cells that lack a nucleus or membrane- bound

Prokaryotes – The first Cells Ø Cells that lack a nucleus or membrane- bound organelles Ø Includes bacteria Ø Simplest type of cell Ø Single, circular chromosome copyright cmassengale 32

Prokaryotes Ø Nucleoid region (center) contains the DNA Ø Surrounded by cell membrane &

Prokaryotes Ø Nucleoid region (center) contains the DNA Ø Surrounded by cell membrane & cell wall (peptidoglycan) Ø Contain ribosomes (no membrane) in their cytoplasm to make proteins copyright cmassengale 33

Eukaryotes Ø Cells that HAVE a nucleus and membranebound organelles Ø Includes protists, fungi,

Eukaryotes Ø Cells that HAVE a nucleus and membranebound organelles Ø Includes protists, fungi, plants, and animals Ø More complex type of cells copyright cmassengale 34

Eukaryotic Cell Contain 3 basic cell structures: Ø Nucleus Ø Cell Membrane Ø Cytoplasm

Eukaryotic Cell Contain 3 basic cell structures: Ø Nucleus Ø Cell Membrane Ø Cytoplasm with organelles copyright cmassengale 35