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Lecture
Lecture

... Care of Offspring • alternative to internal gestation and development: development of the amniotic egg – egg laying animals – monotremes – birds and reptiles – protection of the developing embryo by a protective layer of calcium and proteins in the form of the shell – eggs of fish and amphibians ar ...
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... It is generally true that since there is less molecular motion at low temperatures, chemical reactions--and therefore metabolism--are slowed way down. In fact, for every 10 degree (C) drop in temperature, metabolic rate generally slows down by a factor of about 2.5. You have probably felt the effect ...
4. Collecting duct
4. Collecting duct

... concentrated due to passive flow of H2O out of the tube. As the filtrete moves up the loop of Henle, it becomes more dilute due to passive and active transport of salts out of the tubule. These salts move into the interstitial fluids, and as the tubule passes towards the renal pelvis, water passivel ...
8.2 Cells and Energy
8.2 Cells and Energy

... A stem cell divides into two daughter cells. Each daughter cell is identical to the original parent cell. When mature, these cells also divide. This is how embryos get a supply of stem cells. A growing embryo needs a lot of stem cells to develop tissues and organs. In the laboratory, starting with a ...
The Respiratory System Lecture 1 The Respiratory System The
The Respiratory System Lecture 1 The Respiratory System The

... columnar epithelium that is composed of three types of cells which are: 1. Basal cells: are small cone shape cells rest on the basement membrane not in contact with the lumen their nuclei are close to the basement membrane, these cells are regarded as the stem cells from which new olfactory cells ca ...
Biology First Six Weeks Vocabulary
Biology First Six Weeks Vocabulary

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Slide 1

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Unit 10 - OpenWetWare
Unit 10 - OpenWetWare

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Biology Term 2 - Pearson-Global
Biology Term 2 - Pearson-Global

... • How are some specialised plant cells adapted to their function? • Why is cell differentiation important in plants? Guinness World Records has two entries for ‘the world's largest living tree’. El Árbol del Tule has the largest girth (the length around its trunk) and General Sherman has the greates ...
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Stratified epithelium contains more than one layer named by shape

... • forms epidermis and nervous system ...
doc Vocabulary challenge A list of all the definitions from
doc Vocabulary challenge A list of all the definitions from

... A distinct part of an organism that has a particular function, made of many different tissues Control of water content in the body Movement of water from dilute to concentrated solution across a partially permeable membrane Oestrogen and progesterone are produced here Release of an egg (ovum) from a ...
Human Body study guide
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... These questions/concepts serve as a guide to summarize all of the concepts we learned in Unit 3. Some of the concepts will be more prevalent (seen more) throughout the test compared to others. 1. The human body systems all focus on the concept of maintaining homeostasis. Explain, in your own words, ...
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2 The Necessities of Life

... ATP adenosine triphosphate, a molecule that acts as the main energy source for cell processes. carbohydrate a class of molecules that includes sugars, starches, and fiber consumer an organism that eats other organisms or organic matter decomposer an organism that gets energy by breaking down the rema ...
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respiratory system

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Human-Physiology-Lecture-IV-CellMembranes
Human-Physiology-Lecture-IV-CellMembranes

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Body systemspart 1
Body systemspart 1

... --The study of the human body and how it works is a branch of Biology called ____________. --Anatomy is used by __________, nurses, ____________, and _______________________. --Despite studying the body for centuries, ______________________ about it. --Like a business, your body is divided into sect ...
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What is an organism?

... = groups of many different populations living in one area. ( all the different types of frogs, fish, turtles and cat tails in Mrs. ...
Anatomy & Physiology Chapter 3 – Part 3
Anatomy & Physiology Chapter 3 – Part 3

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Multicellular organisms meet their needs in different ways.
Multicellular organisms meet their needs in different ways.

... asexually can reproduce more often. Asexual reproduction limits genetic diversity within a group because offspring have the same genetic material as the parent. Check Your Reading ...
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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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