Chapter 2 - Cells

define Extracellular

- Outside the cell

Examples of Cilia and Flegella are in human throats

1) In the trachea and bronchi, cilia continuously move a layer of mucus from the lower portions of the lungs to the throat. (i) The mucus traps particles of dirt, microorganisms, and other foreign matter. (ii) This foreign material is then either swallowed or expectorated. (iii)Cigarette smoking paralyzes the motion of the cilia, resulting in an accumulation of foreign substances in the lungs.

Name parts of the abdominal cavity

1. Abdominal cavity - a single large cavity that extends from the diaphragm to the pelvic bones and is lined with a serous membrane called the peritoneum. i. Mesentery - membranous double fold of tissue in the abdomen that attaches various organs to the body wall. a. Supplies blood to the abdominal organs. ii. The abdomen can be divided into quadrants by crossing the umbilicus with imaginary perpendicular lines. a. Umbilicus - the navel. iii. Retroperitoneal space - the area posterior to the parietal peritoneum. iv. Retroperitoneal organs - term given to the kidneys, pancreas, duodenum, and major blood vessels of the abdominal cavity because they are located in the retroperitoneal space. 2. Pelvic cavity - lower portion of the abdominal area. i. Contains the urinary and reproductive organs, as well as part of the gastrointestinal systems. ii. Supported by the pelvic girdle with the pubis, ischium, coccyx, ilium, and sacrum bones, which also provide protection to the intra-pelvic organs.

Describe Nutritional imbalance factors

1. Nutritional imbalances i. Good nutrition is required to maintain good health and assist the cells in fighting off disease. ii. Examples of nutritional disorders than can injure cells and the organism as a whole include: a. Obesity b. Malnutrition c. Vitamin excess or deficiency d. Mineral excess or deficiency

Describe Physical agents

1. Physical agents i. Heat - burns ii. Cold - frostbite iii. Radiation - sickness and tumors

Discuss nervous tissue - dendrites

1. Specialized for the conduction of electrical impulses from one region of the body to another. 2. Contain two basic types of cells: i. Neurons ii. Neuroglia (glial cells) 3. Nervous tissues are found in the brain, spinal cord, cranial nerves, and peripheral nerves. i. Peripheral nerves - all of the nerves that extend from the brain and spinal cord, exiting from between the vertebrae to various parts of the body. 4. Neurons - the main conducting cells of nerve tissue. . Dendrites - projections from the nerve cell body that receive electrical impulses from the axons of other nerve cells and conduct them toward the cell body. i. Axons - projections from the nerve cell body that conduct electrical impulses away from the cell body. Each neuron has only one axon but may have several dendrites

How does the cell membrane act like a door

1. The cell membrane allows selective communication between the intracellular and extracellular compartments while aiding in cellular movement. i. Gives form to the cell ii. Much of the cell's biologic activities are conducted in the cell membrane. iii. Detects signals from outside the cell and transmits them inside. iv Adheres to other cells when tissues form

Discuss the permeability of the cell membrane

1. The cell membrane is selectively permeable. i. Selective permeability - allows some, but not all, substances to pass through a membrane to maintain homeostasis. ii. The separation of the extracellular areas from the intracellular areas helps maintain homeostasis. ii. Various enzymes, sugar molecules, and electrolytes are some of the substances that are allowed to pass freely into and out of the cell. iv. Electrolytes - chemicals made up of salt or acid substances that are dissolved in the blood; they act as ionic conductors when dissolved in a solvent such as water.

What is the nucleus of a cell ?

1. The nucleus is usually round and enclosed in a double nuclear envelope. i. Nuclear envelope has inner and outer lipid membranes. a. Has a protein lining, allowing certain molecules to exit the nucleus. ii. Nucleoplasm - a fluid inside the nucleus that suspends the following structures: a. Nucleolus - a "mini nucleus" made up mostly of ribonucleic acid (RNA) and protein molecules. 1) Has no surrounding membrane. 2) Ribosomes form here and migrate out to the cell's cytoplasm. b. Chromatin - loosely coiled DNA and protein fibers that condense 1) DNA controls protein synthesis. When cells start to divide, the chromatin fibers coil tightly to form chromosomes

What is cytosol

1. the fluid portion of cytoplasm. i. Contains mostly water, as well as glucose, amino acids, fatty acids, ions, lipids, proteins, ATP, and waste products. ii. The site of many chemical reactions required for cells to exist.

Name the 3 basic parts of a cell

1.) Cell membrane - encloses the cell, its nucleus, various organelles, and its cytoplasm. 2). Nucleus - contains the cell's genetic material and controls its activities. 3) Cytoplasm - fills out the cell and its shape

Describe Genetic factors

A. Additional Factors 1. Genetic factors, nutritional imbalances, and physical agents can also cause cell injury and death. 2. Genetic factors i. Chromosomal disorders, such as Down syndrome ii. Abnormal genes can develop by: a. Mutation of a gene during meiosis, which affects the newly formed fetus b. By heredity

What are body regions

A. Body Regions 1. The body is divided into several regions. 2. Appendicular region - includes the extremities and their associated girdles. i. Girdles - the bony structures that attach the limbs to the body. ii. The upper extremity is divided into the arm, forearm, wrist, and hand, and attaches to the body at the shoulder girdle. iii. Axilla - region inferior to the shoulder, or armpit. iv. Antecubital fossa - the bend or crook of the elbow. v. The lower extremity is divided into the thigh, leg, ankle, and foot, and is attached to the body by the hip or pelvic girdle. vi. Popliteal fossa - the space behind the knee. 3. Axial region - consists of the head, neck, and trunk. i. The scalp is the skin layer of the head, excluding the face and ears, that normally is covered with hair. a. Consists of five layers, including, from the external surface moving inward: the skin, subcutaneous tissue, muscle, loose connective tissue, and periosteum. b. The scalp is highly vascular and tends to bleed freely when cut. c. Meninges - the membrane layers within the skull and covering the brain, including, from the outermost to the innermost layers: dura mater, arachnoid, and pia mater. d. Periosteum - a membrane that covers the outside of the skull and all bones. ii. Skull - houses the brain and is composed of two main parts: the cranium and the facial bones. a. Bones of the skull are connected together at special joints known as sutures. iii. Fontanelles, which soften and expand during childbirth, link the sutures. a. The tissue felt through the fontanelles are layers of the scalp and thick membranes overlying the brain. b. Under normal conditions, the brain may not be felt through the fontanelle. c. By the time a child reaches age 2 years, the sutures should have solidified and the fontanelles closed. d. the base of the skull. 1) Contains numerous lymph nodes, the brachial plexus, spinal accessory nerve, and a portion of the subclavian artery. Trunk - further subdivided into the thorax, abdomen, and pelvis

What is a cell membrane (aka plasma membrane)

A. Cell Membrane - like a door 1. Also called plasma membrane, controls movement of substances into and out of the cell The membrane consists of a complete set of neatly arranged molecules and is able to alter its structure depending on the needs of the cell at any time

Describe Chemical Injury

A. Chemical Injury 1. A variety of chemicals may injure and ultimately destroy cells. i. Poisons ii. Lead iii. Carbon monoxide iv. Ethanol v. Pharmacologic agents 2. Cyanide induces cell hypoxia by blocking oxidative phosphorylation in the mitochondria and preventing the metabolism of oxygen. 3. Pesticides block the enzyme acetylcholinesterase, preventing proper transmission of nerve impulses.

Describe Immunologic and Inflammatory Injury (like aids)

A. Immunologic and Inflammatory Injury 1. Inflammation - a protective response that can occur without bacterial invasion. 2. Infection - the invasion of microorganisms that causes cell or tissue injury, which leads to the inflammatory response. 3. The immune system provides protection for the body by providing defenses to attack and remove foreign organisms such as bacteria or viruses. 4. Cellular membranes may be injured by direct contact with the cellular and chemical components of the immune or inflammatory process: i. Phagocytes (lymphocytes and macrophages) ii. Histamine iii. Antibodies iv. Lymphokines 5. Swelling occurs when cell membranes are altered, causing potassium to leak out of the cells and water to flow inward. i. The nuclear envelope, organelle membranes, and the cell membrane may all rupture, leading to death of the cell.

Describe Infectious Injury

A. Infectious Injury 1. Occurs as a result of an invasion of bacteria, fungi, or viruses. i. Bacteria may cause injury by direct action on cells or by the production of toxins. ii. Viruses often initiate an inflammatory response that leads to cell damage and patient symptoms.

Describe Cellular Injury

A. May result from various causes, such as hypoxia (lack of oxygen), ischemia (lack of blood supply), chemical injury, infectious injury, immunologic (hypersensitivity) injury, physical damage (mechanical injury), and inflammatory injury. 1. The manifestation of cellular injury and death depend on how many and which types of cells are damaged. B. Hypoxia 1. Common cause of cellular injury. 2. May result from: i. Decreased amounts of oxygen in the air (such as in carbon monoxide poisoning) ii. Loss of hemoglobin function (such as in carbon monoxide poisoning) iii. Decreased number of red blood cells (such as from bleeding) iv. Disease of the respiratory or cardiovascular system (e.g., chronic obstructive pulmonary disease) v. Loss of cytochromes (mitochondrial proteins that convert oxygen to ATP, such as in cyanide poisoning). 3. Cells that are hypoxic for more than a few seconds produce mediators (substances) that may damage other local or distant body locations. i. Mediators lead to more cell damage, which leads to more hypoxia, which leads to further mediator production, and so forth. a. The result is widespread and potentially deadly tissue damage.

What are organ systems

A. Organ Systems - a group of organs that work together to maintain homeostasis. 1. Organ systems include the skeletal, muscular, respiratory, circulatory, lymphatic, nervous, integumentary, digestive, endocrine, urinary, and genital systems. 2. Combined, the various organ systems form an organism. i. Organism - any individual living thing. ii. The human organism is very complex, consisting of mutually dependent organs and organ systems. 3. The anatomy and physiology of each organ system are described in detail in the following chapters.

Name the 2 General Classes of cells in the human body (hint both start with "S")

A. The human body contains two general classes of cells: 1. Sex cells (also called germ cells or reproductive cells) are in the sperm of males or the oocytes (eggs) of females. 2. Somatic cells (derived from the term soma, meaning "body") include all the other cells in the human body.

What are organs ?

A. Various tissues work together in organs to perform tasks. 1. Together, these components serve to pump blood through the arteries and veins of the circulatory system. B. Examples 1. The skin (integument) contains all four types of tissues and is the largest organ in the body. i. Preserves heat. ii. Prevents fluid loss. iii. Protects against invasion of the body's surface by infection-causing bacteria. 2. Other organs include the liver, spleen, digestive organs, reproductive organs, and special sensory organs.

What is protoplasm

Basically the "snot" inside a cell 1. -a viscous liquid matrix that supports all internal cellular structures (organelles). i. Each cell is a minute mass of this colorless substance. Protoplasm provides a medium for intracellular transport of various substances, such as nutrients, signaling molecules, ATP, and proteins

What are cilia and flagella?

Both are extensions of the cell membrane. Cilia are hair-like and flagella resemble a tail i. Cilia and flagella - structures that extend from certain cell surfaces. a. Cilia - Hair-like projections on the surface of a cell. 1) Often, several cilia are located on a cell. 2) They are capable of motion, and act to move materials over the cell surface.

What is pinocytosis?

Cell drinking 1) Exocytosis - release of secretions from cells that have been accumulated in vesicles. (i) These secretions accumulate within vesicles, which then move to the cell membrane. (ii) The vesicles bond or fuse to the membrane, and the content of the vesicle is eliminated from the cell. (iii)Examples of exocytosis (a) Secretion of digestive enzymes by the pancreas. (b) Mucus secretion by the salivary glands.

What are cells

Cells are the foundation of the human body. 1. In less advanced forms of life, such as an amoeba, the entire organism consists of a single cell. 2. The human body contains single cells grouped together to form complex systems. i. Billions of cells compose the human body.

What is tissue

Cells with a common job grow close to each other and are called tissues

What is Crenation as it relates to cell membrane

Crenation - shrinkage of a cell that occurs when too much water moves out of the cell

What are organs

Groups of tissues that all perform interrelated jobs form organs

What is cell division

I. Cell Division A. Remodeling - the ongoing process of cell renewal due to many cells actively dividing and other cells dying and being replaced by new cells. B. Cell division can occur via two separate, but related, processes: mitosis and meiosis.

Discuss types of tissue

I. of Tissue A. Tissue - groups of similar cells working together, classified anatomically into four types: epithelial, connective, muscle, and nerve. B. Epithelial tissues - tissues that cover all of the external surfaces of the body (such as the skin), cover and line organs within the body (such as the gallbladder), and make up the glands (enabling secretion and absorption to occur throughout the body). 1. Most epithelial tissues have a basement membrane. i. Basement membrane - a noncellular layer that secures the overlying tissues. 2. Epithelial tissue is classified according to the number of cell layers and the shape of each epithelial cell. i. Cell shapes include squamous, cuboidal, and columnar. a. Squamous epithelium - flat sheets. b. Cuboidal epithelium - rows of square-shaped cells c. Columnar epithelium - rows of tall, thin cells. 3. Simple epithelium - consists of a single layer of cells, all of which are in contact with the basement membrane. 4. Stratified epithelium - consists of more than one layer of cells, only one layer of which is in contact with the basement membrane. 5. Pseudostratified epithelium - contains a single layer of cells of varying heights. i. All cells attach to the basement membrane, but some fail to reach the free surface, giving the appearance of multiple layers. 6. Transitional epithelium - consists of layers of stratified cells that change shape from cuboidal to squamous when the organ is stretched. C. Connective tissues 1. Binds other types of tissue together. 2. Connective tissue proper i. Includes those connective tissues with many types of cells and extracellular fibers in a syrup-like ground substance. ii. Dense connective tissue - contains many collagenous fibers and appears white. iii. Loose connective tissue a. Adipose tissue - lies beneath the skin, between muscles, around the kidneys, behind the eyes, in certain membranes of the abdomen, on the heart's surface, and around some of the body's joints. b. Areolar tissue - binds skin to underlying organs and fills in spaces between muscles. c. Reticular connect tissue - helps to create a framework inside internal organs such as the spleen and liver. 3. Supporting connective tissues i. Have a less diverse cell population and a matrix that contains many more densely packaged fibers than connective tissue proper. ii. Protect soft tissues and carry most of or all of the body's weight. iii. The two types of supporting connective tissue are cartilage and bone. a. Cartilage is a rigid connective tissue with a gelatinous matrix that contains an abundance of fibers. 1) Supports, frames, and attaches to many underlying tissues and bones. b. Bone is the most rigid type of connective tissue, with a high mineral content that makes it harder than other types. 1) Establishes the framework of the body. 2) Attaches to muscles and protects as well as supports vital body structures. 4. Fluid connective tissues i. Have distinctive populations of cells suspended in a water matrix that contains dissolved proteins and may be of two types: a. Blood 1) Contains formed elements (red blood cells, white blood cells, and platelets), which are suspended in a liquid extracellular matrix known as blood plasma. 2) Most blood cells are formed in the red bone marrow. b. Lymph 1) Forms as interstitial fluid enters the lymphatic vessels, which return the lymph to the cardiovascular system. D. Muscle Tissue 1. Tissue that overlies the framework of the skeleton; it is located within the substance of the body and invariably enclosed by connective tissue. 2. Muscles are classified by both structure and function. 3. Structurally, muscle tissue is either striated or nonstriated (smooth). i. Striated - muscle in which microscopic bands or striations can be seen. ii. Nonstriated - muscle without striations; smooth muscle is nonstriated. 4. Functionally, muscle is either voluntary or involuntary. i. Voluntary - consciously controlled. ii. Involuntary - not normally under conscious control. 5. The three types of muscle are skeletal muscle, cardiac muscle, and smooth muscle. i. Skeletal muscle - striated voluntary muscle a. Most of the muscles used volitionally in day-to-day activities are skeletal muscles. ii. Cardiac muscle - striated involuntary muscle. a. Also called myocardium b. The heart consists of cardiac muscle. c. Contains less connective tissue than skeletal muscle. d. Relies on pacemaker cells or nodes of tissue in the conduction system for regular contraction. e. Automaticity - under the right circumstances, each cardiac tissue has the ability to generate an impulse. 1) May be caused by hypoxia or electrolyte imbalance in the cardiac cells. iii. Smooth muscle - nonstriated involuntary muscle. a. Can regenerate after being injured. b. Composes hollow internal organ walls (such as the intestines and stomach). c. Typically, we have no conscious control over the function of smooth muscle. E. Nervous Tissues 1. Specialized for the conduction of electrical impulses from one region of the body to another. 2. Contain two basic types of cells: i. Neurons ii. Neuroglia (glial cells) 3. Nervous tissues are found in the brain, spinal cord, cranial nerves, and peripheral nerves. i. Peripheral nerves - all of the nerves that extend from the brain and spinal cord, exiting from between the vertebrae to various parts of the body. 4. Neurons - the main conducting cells of nerve tissue. i. Dendrites - projections from the nerve cell body that receive electrical impulses from the axons of other nerve cells and conduct them toward the cell body. ii. Axons - projections from the nerve cell body that conduct electrical impulses away from the cell body. iii. Each neuron has only one axon but may have several dendrites.

define Intracellular - Inside the cell.

Intracellular - Inside the cell.

What are the 2 primary substances that make up cell membranes

Lipids and proteins i. There is usually a double layer of phospholipid molecules. a. The phosphate portion forms the outer surface. b. The fatty acid portion forms the inner surface. c) This double layer is also called a bilayer

Mitochondria - what are they

Mitochondria are rod-shaped organelles that can be considered the power generators of the cell, converting oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy "currency" of the cell that powers the cell's metabolic activities.. Mitochondria - small, rod-like organelles that function as the metabolic center of the cell. a. Use the process of oxidative metabolism to produce adenosine triphosphate (ATP). 1) ATP - the primary molecule used by cells to store and transfer energy.

What are organelles?

Organelles - microscopic specialized cell structures that perform specific functions required by the cell.

i. Ribosomes - what are they

Ribosomes are like the energy plant for a cell. It makes proteins so the cell has energy. Ribosomes - organelles that contain RNA and protein. a. Interact with RNA from other parts of the cell to join amino acids together to form proteins. b. This interaction takes place in the endoplasmic reticulum.

What is the Endoplasmic reticulum -

a series of membranes in which specific proteins and fats (lipids) are manufactured

Golgi apparatus - what is it

a set of membranes within the cell's protoplasm associated with the formation of various carbohydrate and complex protein molecules.

What are flagella

a. Flagella - tail-like microtubule structures. 1) Propels the cell. 2) Sperm have a tail or flagellum that propels them through the vagina and into the uterus so that fertilization of the ovum may occur.

How do proteins work as make up part of the cell membrane (hint 4 things)

a. They serve as transporters for various molecules (e.g., for use in facilitated and active transport). b. They serve as signal receptors (e.g., as binding sites for drugs and body chemicals, such as epinephrine). c. They act as doorways, called channels, which allow certain molecules to enter or exit the cell. d. They act as ion channels (e.g., to allow the movement of charged molecules, such as sodium, between cells).

What is mitosis and the 4 steps of it

division of the nucleus 1. Cytokinesis - the division of the cytoplasm of a cell. 2. All cells except egg and sperm cells can be divided by mitosis. Division must be precise so that an accurate copy of the DNA information can be made by the new cell. Division of the cell nucleus and protoplasm occurs in the following four stages: i. Stage One (prophase) - two new centriole pairs move to opposite ends of the cell. ii. Stage Two (metaphase) - the chromosomes align near the middle portion (equatorial plane) between the centrioles, and spindle fibers attach to them. iii. Stage Three (anaphase) - the centromere sections of each chromosome are pulled apart to become individual chromosomes and move toward opposite ends of the cell. a. Cytoplasmic division begins during this phase, and continues through telophase. Stage Four (telophase) - chromosomes arrive at each pole, and new nuclear membranes form

What is active transport as related to cell membrane

i. Active transport - movement of a substance against a concentration or gradient. a. Requires energy and some type of carrier mechanism. b. Movement is opposite that of the normal movement of diffusion. c. Mechanism may exchange one substance for another. d. Endocytosis - uptake of material through the cell membrane by a membrane-bound droplet or vesicle formed within the cell's protoplasm. 1) The cell membrane surrounds the material, engulfing it within the cell. 2) Phagocytosis - form of endocytosis that involves solid particles and literally means "cell eating." (i) Occurs commonly when infection-fighting white blood cells consume bacteria and foreign particles. In certain disease states, these cells lose their ability to phagocytize, resulting in life-threatening infections

Discuss diffusion as related to cell membrane

i. Diffusion - movement of particles or solutes from an area of high concentration to an area of low concentration. a. Degree of diffusion depends on the permeability of the membrane to that substance and the concentration gradient. b. Concentration gradient - difference in concentrations of a substance on either side of the membrane. 1) Small molecules diffuse more easily than large molecules. Watery solutions diffuse more rapidly than thicker, viscous solutions

What is facilitated diffusion as related to cell membrane

i. Facilitated diffusion - process by which a carrier molecule moves substances into or out of cells from areas of high concentration to areas of lower concentration. a. Energy is not required; the number of molecules transported is directly proportional to the concentration.

What is osmosis as relates to cell membrane

i. Osmosis - movement of a solvent, such as water, from an area of low solute concentration to an area of high concentration through a selectively permeable membrane. a. Occurs when the membrane is permeable to the solvent but not the solute. b. Movement generally continues until the concentrations of the solute equalize on both sides of the membrane. c. Osmotic pressure - measurement of the tendency of water to move by osmosis across a membrane.

define Proton, Electron, and neutron - Atom Parts

i. Protons -particles that have a positive electrical charge. ii. Electrons - particles that have a negative electrical charge. iii. Neutrons - particles that are uncharged.

What are the 2 kinds of genetic material stored in the nuclear of a cell ?

i. The nucleus contains two different types of genetic material: a. Deoxyribonucleic acid (DNA) - contained in the chromosomes. b. RNA - contained in the nucleoli. 1) Nucleoli - spherical intranuclear structures. c. The nucleus is surrounded by a membrane called the nuclear envelope. The nucleus itself is embedded in the cytoplasm.

How is the cell membrane selectively permeable?

it controls what it allows through it i. Allows certain elements to pass through while not allowing others to do so. Selective permeability - only certain substances can enter or leave the cell

What is a. Lysis -as relates to cell membrane

swelling and bursting of a cell that occurs when too much water enters the cell.

What is homeostatis

the stability of the body's normal internal environment Disruption of homeostasis can have a serious impact from the cellular level up to the organ systems and the entire organism