1. Cells, Tissues & Organs - National 5 Biology
Below is a picture of a typical animal cell These cells in various forms throughout your What is the relation among the cell, tissue, organs, and the system?. A2A Tissues and organs relations are just like: * child and mother * Motherboard and laptop What is the difference between animal tissue and plant tissue?. Study animal and plant cells with BBC Bitesize KS3 Science. Cells are organised into tissues, organs, systems and organisms. 1 · 2 · 3 · 4 · 5; 6; Page 6 of 6.
Elastin permits ligaments to be stretched. Loose connective tissue It is distributed throughout the body. It serves as a packing and binding material for most of our organs. Sheets of loose connective tissue that bind muscles and other structures together are called fascia.
Collagen, elastin, and other proteins are found in the matrix of loose connective tissue. Both dense and loose connective tissue are derived from cells called fibroblasts [ View ], which secrete the extracellular matrix. Adipose tissue Adipose tissue is "fat". There are two kinds found in mammals: The oil is confined within a single membrane-enclosed droplet. Virtually all of the "fat" in adult humans is white adipose tissue.
They also consist of three parts: Blood[ edit ] Blood consists of a matrix - plasma, with several types of cells and cell fragments suspended in it.
The fibres are only evident in blood that has clotted. Blood will be described in detail in chapter 8. Lymph[ edit ] Lymph is similar in composition to blood plasma with various types of white blood cell floating in it.
It flows in lymphatic vessels. Loose connective tissue Connective tissue 'proper' consists of a jelly-like matrix with a dense network of collagen and elastic fibres and various cells embedded in it.
Loose connective tissue[ edit ] Loose connective tissue is a sticky whitish substance that fills the spaces between organs. It is found in the dermis of the skin see diagram 4. Dense connective tissue[ edit ] Dense connective tissue contains lots of thick fibres and is very strong. It forms tendons, ligaments and heart valves and covers bones and organs like the kidney and liver.
Adipose tissue[ edit ] Adipose tissue consists of cells filled with fat. It forms the fatty layer under the dermis of the skin, around the kidneys and heart and the yellow marrow of the bones. It consists of a tough jelly-like matrix with cells suspended in it. It may contain collagen and elastic fibres. It is a flexible but tough tissue and is found at the ends of bones, in the nose, ear and trachea and between the vertebrae see diagram 4.
Bone[ edit ] Bone consists of a solid matrix made of calcium salts that give it its hardness.
Tissues, organs, & organ systems (article) | Khan Academy
Collagen fibres running through it give it its strength. Bone cells are found in spaces in the matrix. Two types of bone are found in the skeleton namely spongy and compact bone. They differ in the way the cells and matrix are arranged.
Tissues, organs, & organ systems
See Chapter 6 for more details of bone. Muscle Tissues[ edit ] Muscle tissue is composed of cells that contract and move the body. There are three types of muscle tissue: Smooth muscle fibres Smooth muscle[ edit ] Smooth muscle consists of long and slender cells with a central nucleus see diagram 4. It is found in the walls of blood vessels, airways to the lungs and the gut. It changes the size of the blood vessels and helps move food and fluid along.
Contraction of smooth muscle fibres occurs without the conscious control of the animal. Skeletal muscle fibres Skeletal muscle[ edit ] Skeletal muscle sometimes called striated, striped or voluntary muscle has striped fibres with alternating light and dark bands.
It is attached to bones and is under the voluntary control of the animal see diagram 4. Cardiac muscle cells are branched cylinders with central nuclei and faint stripes see diagram 4.
ANIMAL ORGAN SYSTEMS
Each fibre contracts automatically but the heart beat as a whole is controlled by the pacemaker and the involuntary autonomic nervous system. A motor neuron Nervous Tissues[ edit ] Nervous tissue forms the nerves, spinal cord and brain. Nerve cells or neurons consist of a cell body and a long thread or axon that carries the nerve impulse. An insulating sheath of fatty material myelin usually surrounds the axon.
Vertebrate Bodies[ edit ] We are so familiar with animals with backbones i. There is a well-defined head that contains the brain, the major sense organs and the mouth, a trunk that contains the other organs and a well-developed tail.
Other features of vertebrates may be less apparent.Basic Biology. Lesson 6: Cells Tissues and Organs (GCSE Science)
For instance, vertebrates that live on the land have developed a flexible neck that is absent in fish where it would be in the way of the gills and interfere with streamlining. Mammals but not other vertebrates have a sheet of muscle called the diaphragm that divides the trunk into the chest region or thorax and the abdomen.
Body Cavities[ edit ] Diagram 4. The body cavities In contrast to many primitive animals, vertebrates have spaces or body cavities that contain the body organs. Most vertebrates have a single body cavity but in mammals the diaphragm divides the main cavity into a thoracic and an abdominal cavity. Heat control is a major function of homeostatic conditions that involves the integration of skin, muscular, nervous, and circulatory systems. The difference between homeostasis as a single cell performs it and what a multicelled creature does derives from their basic organizational plan: The carting away of these wastes is accomplished in my body by the circulatory system in conjunction with the excretory system.
For my house, I have the City of Phoenix sanitation department do that and get to pay each month for their service! The ultimate control of homeostasis is accomplished by the nervous system for rapid responses such as reflexes to avoid picking up a hot pot off the stove and the endocrine system for longer-term responses, such as maintaining the body levels of calcium, etc.
Often this homeostatic control takes the form of negative feedback loops. There are two types of biological feedback: Negative feedback turns off the stimulus that caused it in the first place. When your house cools off below the temperature set by your thermostat, the heater is turned on to warm air until the temperature is at or above what the thermostat is set at.
The thermostat detects this rise in temperature and sends a signal to shut off the heater, allowing the house to cool of until the heater is turned on yet again and the cycle or loop continues. Positive feedback causes an amplification of the stimulus by the reaction. Examples of each will be presented below. Internal components of homeostasis: Concentration of oxygen and carbon dioxide pH of the internal environment Concentration of nutrients and waste products Concentration of salt and other electrolytes Volume and pressure of extracellular fluid Control Systems Back to Top Open systems are linear and have no feedback, such as a light switch.
Closed Systems has two components: Most physiological systems in the body use feedback to maintain the body's internal environment. Extrinsic Most homeostatic systems are extrinsic: Endocrine and nervous systems are the major control systems in higher animals. The nervous system depends on sensors in the skin or sensory organs to receive stimuli and transmit a message to the spinal cord or brain.
Sensory input is processed and a signal is sent to an effector system, such as muscles or glands, that effects the response to the stimulus. The endocrine system is the second type of extrinsic control, and involves a chemical component to the reflex. Sensors detect a change within the body and send a message to an endocrine effector parathyroidwhich makes PTH.
PTH is released into the blood when blood calcium levels are low. PTH causes bone to release calcium into the bloodstream, raising the blood calcium levels and shutting down the production of PTH.
Some reflexes have a combination of nervous and endocrine response. The thyroid gland secretes thyroxin which controls the metabolic rate into the bloodstream.
Falling levels of thyroxin stimulate receptors in the brain to signal the hypothalamus to release a hormone that acts on the pituitary gland to release thyroid-stimulating hormone TSH into the blood. TSH acts on the thyroid, causing it to increase production of thyroxin. Intrinsic Local, or intrinsic, controls usually involve only one organ or tissue.
When muscles use more oxygen, and also produce more carbon dioxide, intrinsic controls cause dilation of the blood vessels allowing more blood into those active areas of the muscles. Eventually the vessels will return to "normal". Feedback Systems in Homeostasis Back to Top Negative feedback control mechanisms used by most of the body's systems are called negative because the information caused by the feedback causes a reverse of the response.
TSH is an example: Positive feedback control is used in some cases. Input increases or accelerates the response. During uterine contractions, oxytocin is produced. Oxytocin causes an increase in frequency and strength of uterine contractions.
Cells to systems
This in turn causes further production of oxytocin, etc. Homeostasis depends on the action and interaction of a number of body systems to maintain a range of conditions within which the body can best operate. Body Systems and Homeostasis Back to Top Eleven major organ systems are present within animals, although some animals lack one or more of them. The vertebrate body has two cavities: