• Study Resource
  • Explore
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Biology Department YEAR 9 SCHEME OF WORK 2014
Biology Department YEAR 9 SCHEME OF WORK 2014

... Candidates will be assessed on their ability to a. understand that there is a wide variety of living organisms and that modern biology classifies organisms on the basis of their structure and how they function b. describe the common features shared by organisms within the five main groups; plants, a ...
Protostome Animals
Protostome Animals

... – Maybe not the champions, but they definitely took the idea natural selection by adaptation to a new level by rapid levels of speciation ...
Unit 1 PIG - Mrs Miller`s Blog
Unit 1 PIG - Mrs Miller`s Blog

... pushes blood fluid out of the capillaries through tiny gaps • Lymph: some tissue fluid is drained into lymphatic vessels ...
CH 3 P3 Lecture
CH 3 P3 Lecture

... • Tissues that regenerate poorly: – Skeletal Muscle ...
Chapter 19
Chapter 19

... • They also take advantage of the host’s respiration, nutrition and all the other functions that occur in living things • Therefore, viruses are considered to be parasites ...
32.4 - share1
32.4 - share1

... develop into any type of blood cell Red cell production is stimulated by a negative feedback mechanism that is sensitive to the amount of oxygen reaching the tissues via blood If the tissues aren’t receiving enough oxygen, the kidney secretes a hormone called erythropoietin, which stimulates the pro ...
Anatomy Final Exam Review
Anatomy Final Exam Review

... • Catalyze Reactions ...
P215 - Basic Human Physiology
P215 - Basic Human Physiology

... • Human body is composed of atoms organized into molecules • Atoms and molecules undergo chemical reactions – Physiology involves control of chemical reactions within the body ...
Semester 1 study guide answer key 2016 Biology Semester 1 Study
Semester 1 study guide answer key 2016 Biology Semester 1 Study

... biomolecules that we need in our bodies. Since matter cannot be created or destroyed only rearranged we are made up of the matter we consume. Cell and Diffusion 24. What do eukaryotic cells and prokaryotic cells have in common? Different? Same: cell membrane, some genetic material, ribosomes Differe ...
Unit 8: Biodiversity Content Outline: Basic Anatomy and Physiology
Unit 8: Biodiversity Content Outline: Basic Anatomy and Physiology

... II. Hierarchy of multi-cellular organism’s structure: A. Cells – This is the basic unit of life. B. Tissues – these are composed from cells with common structure and function. (There are 4 tissue types in most animals.) 1. Epithelial Tissue (This tissue forms protective coverings of structures, such ...
Anatomy and Physiology Part 1-Midterm-12-2011
Anatomy and Physiology Part 1-Midterm-12-2011

... b. osmosis d. phagocytosis The "demolition crew" of a cell consists of certain organelles capable of the removal of cell parts and even of the destruction of the whole cell by intracellular digestive enzyme action. These organelles are called the: a. centrioles c. lysosomes b. peroxisomes d. ribosom ...
Unit A Biology Textbook Unit Review Answers pages
Unit A Biology Textbook Unit Review Answers pages

... 4. A photograph taken through either a transmission electron microscope or a scanning electron microscope is called an electron micrograph. An electron microscope uses a beam of electrons that passes through thin sections of cells and produces an image that shows the surface and texture of a cell, t ...
Mock Exam III
Mock Exam III

... a. occurs when fibrinogen is released from broken platelets b. occurs within red blood cells c. is linked to hypertension and may damage artery walls d. is likely to occur too often in an individual with hemophilia e. is the final step of a clotting process that involves multiple clotting factors ...
Section 18.2 Summary – pages 484-495
Section 18.2 Summary – pages 484-495

... • This food is passed from one _________ to the next in food chains and webs. • In the process of making food, many autotrophs replenish the supply of ______ in the atmosphere. ...
Characteristics of Life- Borton
Characteristics of Life- Borton

... so small that they are usually visible only through a microscope. Some organisms, like bacteria, plankton that live in the ocean, or the Paramecium shown in Figure below are made of just one cell. Other organisms have millions, billions, or trillions of cells. All cells share at least some structure ...
Biology 30 Student Notes Nervous Reproduction_1
Biology 30 Student Notes Nervous Reproduction_1

... from the neurons in the retina leave the eye forming the optic nerve. There is no room for rod or cones cells, consequently this tiny spot is blind.  Cornea: Transparent membrane on the front of the eye, focuses light on the lens and protects the eye  Iris: Circular muscle with a hole in the middl ...
Pathogen
Pathogen

... foreign proteins entering the body? Antibodies and memory cells ...
circulatory system
circulatory system

... to view the amazing human body in never before seen ways. ...
MCAS and Final Review Packet 2013
MCAS and Final Review Packet 2013

... _________________________ - the type of dominance where in the heterozygote both alleles are seen _________________________ - alleles for a particular characteristic are located on the X chromosomes _________________________ - characteristic is controlled by more than one gene 1. Identify the inheri ...
circulatory system
circulatory system

... to view the amazing human body in never before seen ways. ...
Biology is the only subject in which multiplication is the same thing
Biology is the only subject in which multiplication is the same thing

...  CDKs & cyclin drive cell from one phase to next in cell cycle proper regulation of cell cycle is so key to life that the genes for these regulatory proteins have been highly conserved through evolution  the genes are basically the same in yeast, insects, plants & animals (including humans) ...
Circulatory System vs Lymphatic System
Circulatory System vs Lymphatic System

... This means the next time the body sees this type of threat it will be able to very ________________________________________________________________ because it already has the antibodies or at least knows how to make them. ...
Lecture 5
Lecture 5

... • Bone replaces cartilage during development ...
connective tissue
connective tissue

... matrix. The living cell types are red blood cells, also called erythrocytes, and white blood cells, also called leukocytes . The fluid portion of whole blood, its matrix, is commonly called plasma. ...
Membrane Proteins
Membrane Proteins

... 6-Cell Adhesion (Intercellular Joining) Proteins - Special membrane proteins are responsible for the cell junctions (tight junctions, ...
< 1 ... 80 81 82 83 84 85 86 87 88 ... 203 >

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.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report