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Ch_20_lecture_presentation
Ch_20_lecture_presentation

... • Type B (whole blood) donor cannot donate to type A patient • The B agglutinogen of the donor will activate the b agglutinin in the plasma of the type A patient • The a agglutinin of the donor will be activated by the A agglutinogen of the patient ...
File - THE ISLAM SHOW
File - THE ISLAM SHOW

... completed his primary and secondary education in Ankara, he studied arts at Istanbul's Mimar Sinan University and philosophy at Istanbul University. Since the 1980s, he has published many books on political, scientific, and faith-related issues. Harun Yahya is well-known as the author of important w ...
39 | the respiratory system
39 | the respiratory system

... that can damage the lungs or trigger allergic immune responses. The respiratory system contains several protective mechanisms to avoid problems or tissue damage. In the nasal cavity, hairs and mucus trap small particles, viruses, bacteria, dust, and dirt to prevent their entry. If particulates do ma ...
In this unit, we have been exploring homeostasis, t
In this unit, we have been exploring homeostasis, t

... My presentation is about the: ______________________ system The due date of my presentation is: _____________________ ...
Class: - 09 Chapter: - Diversity in Living Organisms
Class: - 09 Chapter: - Diversity in Living Organisms

... i) Diploblastic - organisms which derived from two embryonic germ layers (ecto and endo). ii) Triploblastic - organisms which derived from all the three embryonic germ layers. 3. Coelom: Body cavity or coelom is important for proper functioning of various organs. For example, heart which has to cont ...
One main transport system
One main transport system

... known as the CIRCULATORY SYSTEM. Although, when discussing the movement of oxygen and nutrients in simple organisms, we usually just talk about a "transport system" as there is no blood involved...only in more complex animals do we begin to see blood, hearts, vessels, etc. ...
God`s AMAZING Design
God`s AMAZING Design

... sends an observable chemicals to where characteristic they are needed (like eye and color) sends waste out of the cell ...
Wk 12 Lec 2 notes Resp 1 2015
Wk 12 Lec 2 notes Resp 1 2015

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OCR Document
OCR Document

... takes place, the egg and the sperm fuse together to form a single complete cell known as a zygote with 46 chromosomes (there are 23 chromosomes in each parent). The zygote is then able to reproduce itself by simple cell division (mitosis) to form the embryo, the foetus and eventually the fully forme ...
Document
Document

... being, the laws of its existence and development. The fundamental properties of living things include: metabolism, energy and information, homeostasis, reproduction, growth and development, irritability and movement, heredity and variation, resolution and integrity, structural organization. Evolutio ...
Chapter 37 Immune System
Chapter 37 Immune System

... Many organisms can survive on objects handled by humans. Cleans–ing of dishes, utensils, and countertops with detergents as well as careful hand-washing help prevent the spread of diseases that are passed in this manner. As a result, there are various food rules that restaurants must abide by that a ...
Higher Human Biology Exemplar Question Paper
Higher Human Biology Exemplar Question Paper

... 10. Familial hypercholesterolaemia (FH) is caused by an autosomal dominant allele. The family history below shows the inheritance of FH through three generations. ...
INTRODUCTION
INTRODUCTION

... To appreciate the wonder of being human requires a deep, dedicated systemic point of view. First it is necessary to understand that life happens in cells. You are the result of a mass of several trillion individual cells all working in concert. Whipping those cells into shape to produce you is a mas ...
Department of Biological Sciences 63
Department of Biological Sciences 63

... not useful for the long-distance transportation to the specific direction in the cells because the direction of the thermal motion is random. For example, in an elongated neuron with the length of 1 m, it will take more than 100 years to transport an average-sized protein from the cell body to the n ...
الشريحة 1
الشريحة 1

... These fissures divide the cord into right and left symmetrical halves. The ventral fissure is deeper and wider than the dorsal fissure According to its color in the fresh condition, the spinal cord in cross section appears is differentiated into : A central zone called the gray matter, shaped like t ...
Biology Exemplar Problems
Biology Exemplar Problems

... How is the five–kingdom classification advantageous over the twokingdom classification? ...
Support Material
Support Material

... The present syllabus reinforces the ideas introduced till the secondary classes. It provides the students with new concepts along with an extended exposure to contemporary areas of the subject. The syllabus also aims at emphasizing on the underlying principles that are common to both animals and pla ...
Animal nutrition - Studentportalen
Animal nutrition - Studentportalen

... (gastrovaskulär håla) • alimentary canal (matsmältningskanal) ...
Chapter 28 Animal Tissue and Organ Systems
Chapter 28 Animal Tissue and Organ Systems

... – When wings evolved in birds and bats, they did so by modification of existing forelimbs, not by new limbs sprouting ...
Cell Division – Revision Pack (B3)
Cell Division – Revision Pack (B3)

... There are ethical issues concerning human cloning because people think that the clones will not be ‘true individual’. Cloning animals is useful in a number of ways, but it always carries risks. For example, there is suggestion that GM animals could supply replacement organisms for humans. Some peopl ...
Histology and Embryology Self Test Book
Histology and Embryology Self Test Book

... Ⅳ. Choose the correct answer exists for each question. 1. D 10. C ...
Crustaceans
Crustaceans

... that have a rounded eye. What do you think this will change about the visual information collected by this organ in comparison to eye spots from simpler organisms? 6) There are two arthropods, a hermit crab and a coral-banded shrimp, in the two salt tanks at the back of the classroom. Look at their ...
Respiratory System
Respiratory System

... – Respiratory filtering and cilia • Runny noses and sluggish cilia – The folds and hairs in the nasal cavity cause turbulence in the air we breath • They also heat and humidify inspired air • They get some of the heat and water back from expired air – Figure 22.1 ...
File
File

... “An abundance of amorphous ground substance” “A loose, multidirectional weave of extracellular fibers” “An abundance of different types of fixed and wandering connective tissue” ...
MCAS Review Booklet
MCAS Review Booklet

... What happens to chemical bonds during chemical reactions? How do energy changes affect whether a chemical reaction will occur? Why are enzymes important to living things? Vocabulary chemical reaction reactant product activation energy catalyst enzyme substrate ...
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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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