What are the characteristics of life?
All living things have:
-multiple levels of biological organization
-At the simplest chemical level, atoms join together to form molecules.
-4 types of large biological molecules: carbs, lipids, proteins, & nucleic acids.
-cell is the smallest structural & functional unit that has all of the characteristics of life.
-composed of one or more cells.
All cells come from other cells.
-Tissues are groups of similar cells that perform a particular function.
Several tissues join together to form an organ
-Organ: performs a particular function within the body.
-Groups of organs work together in an organ system. The nervous system consists of the brain, the spinal cord and nerves.
Organisms such as humans and trees are collections of organ systems.
-An organism is any living thing. Organisms can be single-celled or multicellular.
- Species
- A population includes all of the members of a species in a particular area or habitat.
- A community includes all of the different populations in an area.
- An ecosystem is made up of all of the populations in an area and the nonliving environment.
- Biosphere
The biosphere includes everywhere on earth where life exists. Living things acquire materials and energy
Living things cannot survive without a source of energy. Energy is the ability to perform physical or chemical work. Energy is needed to build-up large biological molecules, maintain homeostasis, enable movement and for other purposes.
Producers are organisms that make their own food. •
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What’s the order of biological organization?
Atom Molecule Cell Tissue Organ Organ System Organism
characteristics unique to humans.
- organized
- acquire materials & energy
- homeostatic
- respond to stimuli
- reproduce &grow
- evolutionary history
define: stimuli
change in the internal/external environment that a sensory receptor can detect, leading to nerve impulses in sensory neurons.
define: homeostasis
maintenance of normal internal conditions in a cell by self-regulation
define: genes
unit of heredity existing as alleles on the chromosomes
contains the info in the DNA
define: hypothesis
proposed explanation made on the basis of limited evidence as a starting point for further investigation.
define: theory
system of ideas intended to explain something
Know the roles of consumers
organism that feeds on another organism in a food chain, -primary consumers eat plants, and secondary eat animals
define: reproduce
pass on their genetic information to the next generation
Know the roles of producers
photosynthetic organism at the start of a grazing food chain that makes its own food (green plants)
Know the roles of decomposers
organisms that break down dead or decaying organisms
-decomposers (like herbivores and predators) are heterotrophic (use organic substrates to get their energy, carbon and nutrients for growth and development)
different levels of organization of the human organism.
Atom Molecule Cell Tissue Organ Organ System ---- Organism -A population includes all of the members of a species in a particular area or habitat. -A community includes all of the different populations in an area. -An ecosystem is made up of all of the populations in an area and the nonliving environment. -Biosphere
process of science
observation, question, hypothesis, prediction, conducting of experiment, collection of data, results, support hypothesis?