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Worms - DigitalWebb
Worms - DigitalWebb

... • Closed circulatory system: blood contained within network of blood vessels • Two major blood vessels running from head to tail – Dorsal vessel: blood towards head, functions ...
Question Answers 2(Download)
Question Answers 2(Download)

... substances can increase on one side of the membrane or the other. _________________________39. A water concentration gradient is influenced by the number of solute molecules present on both sides of the membrane. _________________________40. The relative concentrations of solutes in two fluids are r ...
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File - Etna FFA Agriculture

... Contains a protein called hemoglobin which carries oxygen in the blood. Numerous red blood cells contained in the body, these cells cannot repair themselves and die after a period of time. ...
lecture 4 slides/page - University of San Diego Home
lecture 4 slides/page - University of San Diego Home

... available to different types of insects. • Requirements can be quite high: Certain insect flight muscles convert more energy per unit weight than any other animal tissue. ...
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... convert more energy per unit weight than any other animal tissue. ...
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Nutrition, Digestion, Excretion What nutrients are essential for insects?

... convert more energy per unit weight than any other animal tissue. ...
Chapter 3-2
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... Synovial membranes Line joint cavities  Consist of fibrous connective tissue and enclose the joint cavities.  This will be covered in greater detail in the next unit when we talked about joints and articulations. ...
Chapter 1
Chapter 1

... power of dogs for many important jobs, like finding people trapped in avalanches. Now scientists have discovered that man’s best friend can also use its nose to detect cancer. Cancer is a disease in which cells (the body’s most basic unit of life) multiply without stopping. For a long time scientist ...
Bacteria and Viruses
Bacteria and Viruses

... • non-living – no metabolism and can’t reproduce on their own • DNA or RNA core surrounded by a protein coat • use a living cell’s internal structures to reproduce themselves • Capsid – protein coat - often with proteins on it that help it invade a host cell – often highly specific • once inside the ...
Maintaining a Dynamic Equilibrium The Need for Homeostasis
Maintaining a Dynamic Equilibrium The Need for Homeostasis

... Organisms live in a world of changing conditions. But, to remain alive, every organism needs to keep the conditions inside of itself fairly constant. An organism must have ways to keep its internal conditions from changing as its external environment changes. This ability of all living things to det ...
Biology Review
Biology Review

... A. I am one of the first to see the cell structure for cell division. B. I found that by combining amino acids and electrical current I could create protocells. C. I invented a blood preservation technique still used today. D. I am the head of many cancer associations & head researcher. E. I invente ...
Chapter 27 Introduction to Animals Chapter 27 Section 1
Chapter 27 Introduction to Animals Chapter 27 Section 1

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inv5homeostasis - Falco-Mexicanus
inv5homeostasis - Falco-Mexicanus

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key words/concepts
key words/concepts

... PRODUCED ALSO IN BONE M,ARROW  THYMUS GLAND TO BECOME SPECIALIZED: ATTACK VIRUSES HIDING INSIDE CELLS; VIRUS ATTACK COORDINATED BY HELPER T CELLS (CD4 CELLS); AIDS, HIV: ATTACKS CD4 CELLS; WEAKENED IMMUNE SYSTEM; PERSON SUSCEPTIBLE TO OTHER VIRUSES, BACTERIA, FUNGI, PARASITES, PNEUMONIA, CANCER; H ...
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... the presence of an extra chromosome in the body cells of humans. This extra chromosome occurs in a gamete as a result of ...
Ch. 19 (Part I): Bacteria (Monera)
Ch. 19 (Part I): Bacteria (Monera)

... -Lack membrane-bound nucleus (prokaryotes) -Ribosomes are slightly different -Smaller than almost all other organisms -Large, single molecule of DNA (w/ extra circular pieces = plasmids) -Other possible structures: ** capsule: ** flagella: whip like tail for locomotion ** cilia: ** chlorophyll: opti ...
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... Irritability: is the ability to initiate nerve impulses in  response to stimuli form 1.Outside the body‐eg: touch , light waves  2.Inside the body‐eg: change in concentration of  carbondioxide in the blood alters respiration. In the body this stimulation may be described as partly  electrical and p ...
Biology Review
Biology Review

... 5. A nucleotide is made of a phosphate group, a 5-carbon sugar (ribose or deoxyribose), and a ___________. 6. All organic molecules contain the element ______________. 7. Eukaryotes reproduce asexually by ____________. 8. Eukaryotes reproduce sexually by ____________. 9. Prokaryotes reproduce asexua ...
Anatomy and Physiology Summer Review HO2/EMT Answer Sheet
Anatomy and Physiology Summer Review HO2/EMT Answer Sheet

... ____ 15. The dorsal cavity is one long, continuous cavity. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. ____ 16. The study of the processes of living organisms, or why and how they work, is ____. a. anatomy c. pathophysiology b. physiol ...
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Hematology PowerPoint

... Prothrombin in plasma+ Calcium ions converts to Thrombinthe thrombin acts as an enzyme and changes FibrinogenFibrin creating a mesh that traps red blood cells, platelets and plasma creating a blood clot. ...
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Unit 1 Notes Packet - ALL

... storing molecular information and transferring this important information from a cellular generation to the next in the process of binary fission/mitosis. This would “create” the ability to reproduce cells or organisms, which would come into existence with step 4. D. Step 4 - Protobiont membrane for ...
Lesson 24
Lesson 24

... If we pull out or pinch off any tiniest bit from any part of a plant or an animal and examine it under microscope we will find hundreds and thousands of unit structures of well-defined shapes – the cells. In fact, every organism including human beings starts life only as a single microscopic cell. T ...
2 1 Respiratory System
2 1 Respiratory System

... Exchanging O2 and CO2 How does O2 get to our cells? O2 and other gases get to our body when we inhale, then red blood cells transport the molecules throughout the body. Why can’t we keep CO2 inside our bodies? CO2 is a toxic gas. ...
Packet - Humble ISD
Packet - Humble ISD

... transferred to the brain through the ________________. The semicircular canals in the ear are for ____________ not hearing, also not involved in hearing is the ____________________ which is used for drainage to the sinuses. ...
Document
Document

... A laboratory investigation included examining prepared slides of pond water. Single-celled organisms with a nucleus and either cilia or flagella were visible. These organisms probably belong to the kingdom ...
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Cell theory



In biology, cell theory is a scientific theory which describes the properties of cells. These cells are the basic unit of structure in all organisms and also the basic unit of reproduction. With continual improvements made to microscopes over time, magnification technology advanced enough to discover cells in the 17th century. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, also known as cell biology. Over a century later, many debates about cells began amongst scientists. Most of these debates involved the nature of cellular regeneration, and the idea of cells as a fundamental unit of life. Cell theory was eventually formulated in 1838. This is usually credited to Matthias Schleiden and Theodor Schwann. However, many other scientists like Rudolf Virchow contributed to the theory. Cell theory has become the foundation of biology and is the most widely accepted explanation of the function of cells.The three tenets to the cell theory are as described below: All living organisms are composed of one or more cells. The cell is the most basic unit of life. All cells arise from pre-existing, living cells, by biogenesis.
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