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change over time
change over time

...  reproductive: members of 2 pops. can’t interbreed  behavioral: two pops. have different habits ...
Introduction to Biology
Introduction to Biology

... constantly to build molecules (synthesis) and cells and to break down (digest) substances (such as breaking down food for nutrition) b. Organisms must transport nutrients to be used in cellular respiration to produce energy. c. An organisms’ chemical reactions are called its metabolism ...
Spring Semester Biology Review
Spring Semester Biology Review

... adaptations include catcus with spines for protection and the closing of the stomata for prevention of water loss. Animals that are camouflaged or mimic other animals are also examples of adaptations. Dichotomous Keys can be used for identification of organisms using opposing statements. In each pai ...
Lecture 7b Invertebrates: Sponges, Cnidaria, Flatworms, Nematodes
Lecture 7b Invertebrates: Sponges, Cnidaria, Flatworms, Nematodes

... Sessile animals Lack true tissues; Have only a few cell types, cells kind of independent • Most have no symmetry • Body resembles a sac perforated with holes, system of canals. • Strengthened by fibers of spongin, spicules ...
CP Biology Name Date Period HOMEWORK PACKET UNIT 1A
CP Biology Name Date Period HOMEWORK PACKET UNIT 1A

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Name Marine Biology--Mr. Nelson LAB: SPONGES AND

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Evolution Guided Notes
Evolution Guided Notes

... These ________________ (simple), anaerobic cells were able to exist in Earth’s early atmosphere As Earth’s atmosphere and conditions changed, ___________________ prokaryotes evolved, using sunlight to produce food. o What molecule do photosynthetic organisms produce as waste? ___________ ...
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Evolution - Effingham County Schools

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Animals – Invertebrates Part 1

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Evolution PPT

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Chapter 7
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Evolution Notes

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Chapter Six Section one and two Study Guide Outline Teacher Copy

... c. Selection- nature “selects” organisms to survive based on how well they can adapt. d. Variation- differences between members of the same species. e. Environmental Change – different events that can cause organisms to leave an area or die out. ...
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Evolution Notes Pages

... Some of that oxygen was generated by photosynthetic cyanobacteria Some came from the chemical separation of water molecules into oxygen and hydrogen. Oxygen drove some life forms to extinction Others evolved ways of using oxygen for respiration ...
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Aquatic Diversity

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Clues About Evolution - Science327-8

... organisms that lived in the past. However, the fossil record is incomplete, or has gaps, much like a book with missing pages. • Scientist can use fossils to show that many simpler forms of life existed earlier in Earth’s history. • Fossils provide evidence that evolution has occurred on Earth. ...
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Ch. 27 Invertebrates

... Invertebrates are organisms that do not have a backbone! Phylum Porifera Sponges - about 9,000 species Characteristics: ~ asymmetrical ~ lack tissues and organs ~ body wall has 2 cell layers with many pores ~ internal cavity lined with food filtering choanocytes (collar cells) ~ live in marine water ...
Chapter 4 Notes - Geneva Area City Schools
Chapter 4 Notes - Geneva Area City Schools

... • Communities are groups of various species that live in the same habitat and interact with each other. • Every population is part of a community. ...
Chapter 4 The Organization of Life
Chapter 4 The Organization of Life

... • Communities are groups of various species that live in the same habitat and interact with each other. • Every population is part of a community. ...
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How are living things organized?

... How are Living Things Organized? • An organism is a living thing that can carry out life processes by itself. • Unicellular organisms are made up of just one cell that performs all the functions necessary for life. • Unicellular organisms do not have levels of organization. ...
Animal Physiology Powerpoint
Animal Physiology Powerpoint

... Circulation in Sponges • The simplest circulatory system is in sponges – Probably similar to the first circulatory system in our common ancestor ...
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Precambrian body plans



Until the late 1950’s, the Precambrian era was not believed to have hosted multicellular organisms. However, with radiometric dating techniques, it has been found that fossils initially found in the Ediacara Hills in Southern Australia date back to the late Precambrian era. These fossils are body impressions of organisms shaped like disks, fronds and some with ribbon patterns that were most likely tentacles.These are the earliest multicellular organisms in Earth’s history, despite the fact that unicellularity had been around for a long time before that. The requirements for multicellularity were embedded in the genes of some of these cells, specifically choanoflagellates. These are thought to be the precursors for all multicellular organisms. They are highly related to sponges (Porifera), which are the simplest multicellular organisms.In order to understand the transition to multicellularity during the Precambrian, it is important to look at the requirements for multicellularity—both biological and environmental.
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