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... Churning movements of the stomach mechanically breakdown of food and acid in the stomach chemically breaks down food ...
PART 1. Principles of development in biology
PART 1. Principles of development in biology

... the jaw musculature seems to be homologous to the original gill support musculature. Thus, the vertebrate jaw appears to be homologous to the gill arches of jawless fishes. But the story does not end here. The upper portion of the second embryonic arch supporting the gill became the hyomandibular bo ...
Blood Powerpoint Ch 6
Blood Powerpoint Ch 6

... • 12 or more clotting factor proteins and Calcium ions make clots. • Prothrombin activator is released at cut or bruise • Calcium helps convert prothrombin to thrombin which cuts two short amino acid chains from two fibrinogen threads. • They join end to end in ropes making a framework clot. ...
MAINTENANCE INTRODUCTION OBJECTIVES ALIMENTARY
MAINTENANCE INTRODUCTION OBJECTIVES ALIMENTARY

... layer called the endoderm and an outer layer called the ectoderm. Since the foregut and hindgut develop from the ectoderm, they have a cuticular lining similar to the outer cuticle that makes up the exoskeleton. Just as the exoskeleton is made up chitins and proteins, so is the cuticular lining in t ...
Biology 11 – Human Anatomy Lecture
Biology 11 – Human Anatomy Lecture

... 2. Histology is the microscopic study of tissues C. Organ level 1. An organ is an combination of 2 or more tissue types that performs a specific function 2. Examples include the heart, liver, pancreas, bones, skin, etc. 3. Each organ has one or more primary tissues and several secondary tissues a. I ...
The Lower Respiratory Tract Histology
The Lower Respiratory Tract Histology

... all those contents will form the pulmonary surfactant which lowers the alveolar surface tension, the deficiency of this substance in the newborn will cause “Respiratory Distress syndrome (RDS) of the newborn”. Those cells and type 1 cells are destroyed by the inhalation of NO2 gas. -The surfactant l ...
Glossary
Glossary

... Homeodomain  transcription  factor   important  for  the  development  of   posterior  structures  in  the   Drosophila  embryo   Homeodomain  transcription  factor   important  for  the  development  of   trophoblast  cells  in  the   mammalian ...
Review: Circulation and Respiration
Review: Circulation and Respiration

... Directions: Use the words below to complete the following description of the breathing process. You may use a word more than once. When you inhale, or breathe in, the diaphragm pulls down the abdomen and allows the lungs to fill with air. The air enters the body through the nose, where it is filtere ...
Anatomy And Physiology Unit Exam Answer Key
Anatomy And Physiology Unit Exam Answer Key

... Creates framework of body, protects internal organs, produces blood cells, and acts as levers for muscles. Produces movement, produces body heat, maintains posture. Coordinates and controls body activities. Carries oxygen and nutrients to body cells; carries waste products away from cells. Carries s ...
Lymphatic System
Lymphatic System

... • Produce lymphocytes: type of white blood cell that produce antibodies. • House macrophages: type of white blood cell that eat bacteria and such. • Lymph node swelling is the result of the increased production of wbc and trapping the foreign objects. ...
Starr Chapter 3 - Seattle Central College
Starr Chapter 3 - Seattle Central College

... Intestinal bacteria make vitamins that mammals cannot, and they crowd out more dangerous germs. Cell for cell, bacteria that live in and on a human body outnumber the person’s own cells by about ten to one. Escherichia coli is one of the most common intestinal bacteria of warm-blooded animals. Only ...
Human Body Systems
Human Body Systems

... All the systems play a part. How do they interact? Which one is the most important? ...
Chapter 1
Chapter 1

... - gene - functional unit of heredity - contains DNA - dominant - expressed in F1 hybrid - recessive - not expressed in F1 hybrid Test cross - breeding of an unknown organism with a true-breeding recessive organism fig. 4.4 Mendel’s Law - allele - alternate form of a gene 1) Law of Segregation - alle ...
Unit 4: Excretion and Waste Management
Unit 4: Excretion and Waste Management

... The earthworm uses a series of tubules to remove wastes from the blood and body cavity. Cells lined with cilia surround a funnel-like structure (the nephrostome) and draw fluids from the body cavity into tiny tubules. The wastes are stored as urine and are released through small pores (nephridiopor ...
Unit VII: Animal Structure and Function, Part I
Unit VII: Animal Structure and Function, Part I

... adaptation due to natural selection and over the short term by physiological responses. + How do animals obtain energy from the environment? + How do animals obtain O2 for cell respiration while disposing of the waste gas CO2? + How do animals respond to pathogens? ...
Biology Concepts to Study
Biology Concepts to Study

... C. LIPIDS: used for energy storage, and as hormones (fats, oils, & waxes) D. NUCLEIC ACIDS: the genetic material of the cell (DNA & RNA) ...
A-P Chapter 3
A-P Chapter 3

... synthesizes new molecules and organelles. 2. During the S phase of interphase, the DNA of the cell is replicated in preparation for cell division. 3. During the G1 and G2 phases of interphase, the cell grows and other structures are ...
Cells, diffusion and osmosis - Pearson-Global
Cells, diffusion and osmosis - Pearson-Global

... When one molecule hits another, both of them change course. Figure 2.13 shows how one ammonia molecule might move around. Each change in direction happens when the molecule bumps into another one. When the lid of the ammonia bottle is first taken off, there are a lot of ammonia molecules inside the ...
CAPT Biology Concepts Study Sheet
CAPT Biology Concepts Study Sheet

... C. LIPIDS: used for energy storage, and as hormones (fats, oils, & waxes) D. NUCLEIC ACIDS: the genetic material of the cell (DNA & RNA) ...
Development ch. 42
Development ch. 42

... Regulate development of entire segments of the body ◦ Although their functions differ in different animals, homeobox genes code for transcription factors that regulate the transcription of many other genes ◦ Each homeobox gene has major responsibility for the development of a particular region in th ...
Lecture #17 - Suraj @ LUMS
Lecture #17 - Suraj @ LUMS

... Transport Systems in Animals ...
Notes 1
Notes 1

... subenin due to which it can’t be penetrated by gases and water. Cork tissue protects plant from injuries, germs and water loss. Cork is light so is used for making products like bottle stoppers, shuttle cork. b) Complex Permanent Tissue: Complex permanent tissue is composed of different types of cel ...
No Slide Title
No Slide Title

... Slide 21.13 ...
Second Semester Anatomy
Second Semester Anatomy

... How Do You Taste? • Gustatory cells- respond to chemicals that are dissolved in saliva • Taste buds- receptor sites for tastes. Most are on the tongue. Some are on the roof of the mouth and cheeks • Papillae- on the sides of this structure is where taste buds are found ...
body systems overview - Mercer Island School District
body systems overview - Mercer Island School District

... • Most arteries contain oxygenated blood • Blood is under greater pressure (most arteries protected deeper within body) • Thick walled vessels • Muscular walls expand/ contract to help move blood ...
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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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