Section 1.1 (Exam 1) Flashcards
Living Organisms Have a Common Origin and Share Similarities
Common characteristics = ___________________________
Common Ancestors
Earth formed how many years ago?
4.5~4.6 billion years ago
Life evolved how many years ago?
4 billion years ago
Events necessary for life to evolve in the beginning
Nucleic acids that reproduce for protein synthesis and biological molecules being enclosed by membranes made of fatty acids
Organisms all used to be
Single cell and prokaryotes
Bacteria and Archaea led to the evolution of
Eukarya
What happened 2.5 billion years ago?
Photosynthesis occurred for the first time (by organisms like cyanobacteria), introducing oxygen and changing life of Earth
What did photosynthesis’ evolution change about the organisms on Earth?
Introduction of oxygen led to aerobic metabolism instead of anaerobic metabolism
What is metabolism?
Chemical reactions within cells that convert food into energy
What happened 500 million years ago?
Oxygen accumulated and led to the formation of the ozone layer, which absorbs UV radiation, lowering temperatures and allowing life to move to land
Cell specialization helped multicellular organisms do what?
Grow larger and become more efficient and gathering resources and adapting to their environment
Similar cell types develop together into?
Tissues
Different tissue types develop together into ________ for specific functions, which can then be grouped into ____________________________.
Different tissue types develop together into organs for specific functions, which can then be grouped into organ systems.
What must organisms acquire from their environment to survive?
Nutrients
What types of work does the body do?
Work, biochemical work, electrical work
Breaking down nutrients provides raw materials for the manufacturing of __________________________ and _________ to do work.
Breaking down nutrients provides raw materials for the manufacturing of organism’s structures and energy to do work.
Maintenance of the narrow range of conditions in the internal environment
Homeostasis
What is the function of sensory mechanisms?
Allow us to sense the world around us
What is the function of effector mechanisms?
Makes you perform actions in response to things that are sensed.
What is the function of signaling mechanisms?
They help the sensory information be communicated to the effector mechanisms, which then take action.
Groups of living organisms of the same species are __________.
Populations
Populations of species that live and interact in a defined area form a _________.
community
Major ecosystems that cover broad geographic areas with distinctive physical features and communities are known as ________.
biomes
Communities together with their physical environments constitute a(n) _______________.
ecosystem
All of the biomes on our planet make up the __________.
biosphere
