Chapter 11 - Human Body Systems Flashcards
(120 cards)
1
Q
What is one of the fundamental principles of biology revealed from the study of the human body?
A
The correlation of form and function.
2
Q
Define anatomy.
A
The study of an organism’s body parts (form).
3
Q
Define physiology.
A
The study of the function of an organism’s body parts (function).
4
Q
What is the structural hierarchy of an organism from largest to smallest?
A
1) Organism
2) Organ System
3) Organ
4) Tissue
5) Cell
5
Q
Define an organ system.
A
A team of organs that together perform an important body function. (Ex. Circulatory System.)
6
Q
Define an organ.
A
Consists of two or more types of issue that work together to perform a specific function. (Ex. Heart)
7
Q
Define a tissue.
A
An integrated group of similar cells that together perform a function.
8
Q
Define a cell.
A
The basic units of an organism that exist by the trillions in human beings.
9
Q
What are the four different types of tissues?
A
1) Connective Tissue
2) Epithelium
3) Nervous Tissue
4) Muscle Tissue
10
Q
Define connective tissue.
A
Consists of cells scattered throughout an extracellular matrix.
11
Q
What are three common examples of connective tissue?
A
1) Blood
2) Cartilage
3) Bone
12
Q
What is the most common kind of connective tissue in the human body?
A
Loose connective tissue that is a matrix of woven fibers that help fold other tissues and organs in place.
13
Q
What type of connective tissue stores energy in the form of fat globules and provides insulation and padding?
A
Adipose Tissue.
14
Q
What is another name for epithelial tissue?
A
Epithelium.
15
Q
Define epithelium.
A
Sheets of tightly packed cells that are fused together. (The skin/epidermis.
16
Q
What does Nervous Tissue do?
A
Communicates Signals Between different parts of the body.
17
Q
What are neurons?
A
The individual cells that can transmit rapid electrical signals along spindly extensions.
18
Q
What is muscle tissue composed of?
A
Bundles of long cells called muscle fibers that contain special proteins that allow it to contact.
19
Q
What are the three different types of muscle tissues?
A
1) Smooth Muscle - Found in many body systems like the walls of the digestive tract and blood vessels. Contracted via involuntary signals.
2) Cardiac Muscle - Found in hearth tissue. Branch and join one another to form a large interconnected tissue. This allows the heart to beat as one coordinated muscle contraction. Also involuntary contraction.
3) Skeletal Muscle - Attached to the bones via tendons and allows movement. Appears striped under a microscope. For the most part under voluntary control.
20
Q
What is homeostasis?
A
The tendency of the human and animal bodies to remain in a relatively constant state despite external changes.
21
Q
What disease is a breakdown in the body’s process of homeostasis?
A
Diabetes.
22
Q
What is the integumentary system?
A
Organs such as the skin, hair, and nails that protect the body against physical harm.
23
Q
What structures do the skin contain aid in temperature regulation?
A
1) Muscles that can produce heat via shivering.
2) A layer of fat the provides insulation
3) Blood vessels on the surface of the skin that can regulate the amount of heat by widening and narrowing.
24
Q
What is the most common mechanism in animals to maintain homeostasis?
A
Negative Feedback.
25
What is negative feedback?
A form of regulation in which the result of a process inhibits that very process.
26
What is the job of the digestive system?
To extract energy and nutrients from food.
27
What is the alimentary canal?
The human digestive system that is divided into specialized digestive organs.
28
Describe the trip of food through the digestive system.
1) Mouth/Oral Cavity - The site of ingestion and beginning of mechanical (teeth) digestion and chemical (saliva) digestion. Tongue is also important to taste and shape food into a ball and move it into the pharynx.
2) Pharynx - The intersection of the mouth, esophagus and trachea. A small flap called the epiglottis moves to cover the entrance to the trachea and directs food down the esophagus.
3) Esophagus - A muscular tube that connects the pharynx to the stomach. Food moves via muscle contractions called peristalsis. (That's why you can swallow while upside-down.)
4) Stomach - Has elastic folds that can stretch out to hold large amounts of food and drink. Cells lining the stomach secrete gastric juice that contains enzymes like pepsin that help digest proteins and other molecules. The walls of the stomach churn the food and gastric juice to produce chyme. A sphincter periodically opens to send a small squirt of chyme into the intestines. Takes 2-6 hrs for the stomach to empty.
5) Small Intestine - Narrow but long tube where chemical digestion is completed by enzymes. It is also the primary site of nutrient absorption.
6) Large Intestine - The main portion of the large intestine is the colon where water is absorbed from the alimentary canal and returned to the bloodstream. Remaining waste is formed into feces and stored in the last six inches of the large intestine called the rectum.
7) Anus - Two sphincter muscles regulate the opening of the anus. One is voluntary and the other is involuntary.
29
What are the accessory organs of the digestive system and what do they do?
1) Liver - Secretes Bile into the small intestine via a duct.
2) Gallbladder - Can store the bile produced by the liver to be secreted later.
3) Pancreas - Liquid secreted by the pancreas via a duct into the small intestine helps neutralize stomach acid and continues the chemical digestion of food.
4) Salivary Glands - Secrete saliva into the mouth. Saliva contains the digestive enzyme salivary amylase which breaks down starches into simple sugars.
30
How are nutrients absorbed in the small intestine?
The epithelial tissue lining the inside of the small intestine is extensively folded into tiny finger-like extensions called villi. In turn, each cell along the villi has microscopic projections called microvilli. This creates a large surface area where absorption can occur.
31
What is a ball of food called?
A bolus.
32
What is the process by which food is used in the body? Describe it step by step.
1) Ingestion - All animals ingest other organisms.
2) Digestion - Via either mechanical or chemical means. Make the food small enough to absorb into the body. Must get broken down into molecular building blocks before use by the body.
3) Absorption - Uptake of nutrients mostly by the villi and microvilli that line the small intestine. From there those nutrients are transported to the rest of the body.
4) Elimination - The disposal of undigested matter from the body. This waste accumulates in the rectum and is expelled via the anus.
33
What are the USDA Recommended Daily Amounts for the Five Food Groups?
1) Fruits - 2 Cups
2) Vegetables - 3 Cups
3) Grains - 8 Ounces
4) Protein - 6.5 Ounces
5) Dairy - 3 Cups
34
What are essential nutrients?
Materials the body cannot make by itself.
35
What are the four classes of essential nutrients?
1) Minerals - Inorganic chemical elements required to maintain health, such as calcium and iron.
2) Vitamins - An organic nutrient required in your diet in only very small amounts. Some are water soluble and others are fat soluble. (C and B = water; A, D, E, and K = fat)
3) Essential Fatty Acids - Used to make fats and other lipids. An example is omega-3 fatty acids that maintain the body's metabolism and reduce inflammation.
4) Essential Amino Acids - Eight of the twenty amino acids must be obtained from diet because human cells cannot make them. Infants require a ninth. Meat of combination of plant proteins can contain all eight essential amino acids.
36
What are seven illnesses or malfunctions of the digestive system?
1`) Acid Reflux - Caused by the backflow of partially digested food back into the esophagus.
2) Gallstones - Solid crystals of bile that can obstruct the gallbladder or its ducts.
3) Constipation - Movement of feces is slowed and too much water is reabsorbed. Feces becomes compacted.
4) Appendicitis - Infection of the appendix (small extension on the large intestine). Cured via removal.
5) Cholera - Infection of the small intestine that releases a toxin the produces diarrhea that can lead to sever dehydration.
6) Inflammatory Bowel Disease - Caused by painful inflammation of the intestinal wall.
7) Ulcer - Mucus protecting the lining of the stomach is infected and eroded leading to a gastric ulcer.
37
What is gastric bypass surgery?
The most common weight loss surgery in the United States. stomach is reduced in size to a small pouch and a portion of the small intestine is attached to the pouch, bypassing a large portion of the stomach. Absorption is reduced and patients feel full sooner.
38
What are three problems that result form nutritional imbalances?
1) Obesity - Defined as an inappropriately high BMI (ratio of weight to height). One third of Americans are Overweight and another third are obese.
2) Malnutrition - Caused by a diet that either lacks sufficient calories or nutrients. Affects 1 billion people. Most common form is protein deficiency.
3) Eating Disorders - Anorexia Nervosa is an example where someone starves themselves out of fear of gaining weight. Bulimia is a pattern of binge eating followed by vomiting.
39
What is the job of the respiratory system?
To facilitate the exchange of Oxygen and Carbon Dioxide between an organism and its environment.
40
Describe the movement of air through the respiratory system.
1) Nasal Cavity - Through the nostrils and mouth it enters and is filtered, passed over smell receptors, warmed, and moistened.
2) Pharynx - The opening at the back of the throat that serves as the junction between the digestive and respiratory system.
3) Epiglottis - Opens and allows air to move into the trachea.
4) Trachea - Conveys air from the pharynx.
5) Larynx - A pair of vocal chords that vibrates to produce sound.
6) Bronchi - Trachea branch into two bronchi that each lead to a lung.
7) Bronchioles - The bronchi branch into smaller and smaller tubes.
8) Alveoli - Small sacs at the end of each bronchiole that are the actual site of gas exchange.
9) Diaphragm - A sheet of muscle that forms the border between the chest cavity and the abdomen. Controls inhalation and exhalation.
41
What happens during inhalation and exhalation?
Inhalation - Air is inhaled. Rib Cage Expands. Diaphragm Contracts (Moves Down)
Exhalation - Air Expelled. Rib Cage Gets Smaller. Diaphragm relaxes (Moves Up)
42
What are four issues faced in the Respiratory System?
1) Bronchitis - Caused by Infection of the Bronchioles by viruses and produces a cough and mucus production.
2) Emphysema - Progressively Worsening Shortness of breath often caused by long term exposure to tobacco smoke or air pollution.
3) Asthma - A long term inflammation of the airway.
4) Upper Respiratory Infections - Viral and Bacterial infections are often the cause and these infections occur in the nose, pharynx, or larynx.
43
What is the job of the circulatory system?
An internal transport network that allows materials to diffuse in and out.
44
What is the cardiovascular system?
Consists of the heart and blood vessels. The heart pumps blood through a branching series of tubes and the blood carries nutrients and wastes between different locations in the body.
45
What are the major parts of the circulatory system?
1) Heart - Receives Blood Through the Veins and Pumps it Out Into the Arteries.
2) Arteries - Vessels that Carry Oxygenated Blood Away From the Heart.
3) Arterioles - The smaller tubes that branch from arteries.
4) Capillaries - Tiny blood vessels that run through nearly every tissue in the body. They have thin walls to allow for easy exchange of materials between the blood and the cells of the body. Vital organs have a continuous supply of blood but other areas are only when needed.
5) Veins - Vessels that return deoxygenated blood to the heart.
6) Venules - The small tubes where blood exits the capillaries.
46
What are the two circuits in the human cardiovascular system?
1) Pulmonary Circuit - Shuttles Blood From the Heart to the Lungs where CO2 is expelled and O2 is picked up and then back to heart.
2) Systemic Circuit - Carries Oxygenated blood from the heart to the rest of the body and deoxygenated blood to the heart from the body.
47
What are the three types of blood vessels and what is their function?
1) Veins - Deoxygenated Blood Back to Heart
2) Arteries - Oxygenated Blood to Body
3) Capillaries - The Meeting place to join Arterioles to Venuoles.
48
What are the differences between arteries and veins?
1) Wall Thickness - Arteries have thicker walls due to the high blood pressure from the hearth pumping more blood into the arteries than can flow. Capillaries have thin leaky walls.
2) Valves - Only veins have valves to ensure the flow of blood in the right direction.
49
What are the similarities between arteries and veins?
Each have a layer of smooth muscle to regulate blood pressure.
Each have connective tissue that allows blood vessels to stretch.
50
What fluid facilitates the exchange of materials between cells and the blood?
Interstitial fluid.
51
What are three things that can go wrong in the circulatory system?
1) Hypertension - High Blood Pressure that affects 25% of American Adults and significantly increases the risk of a heart attack.
2) Heart Disease - Results from the build up of fatty deposits that block the arteries that supply the heart with oxygen.
3) Anemia - Abnormally low amount of hemoglobin or red blood cells. Body does not get enough oxygen as a result.
52
What organ is the central hub of the circulatory system?
The Heart.
53
Describe the flow of blood through the heart.
1) Into the Heart Through the Inferior and Superior Vena Cava. Bring Deoxygenated blood into the heart.
2) Right Atrium
3) Right Ventricle Which pumps blood into the lungs via pulmonary arteries.
4) Lungs - As it flows through capillaries and alveoli, blood becomes rich in oxygen.
5) Left Atrium
6) Left Ventricle
7) Aorta
8) Back into the body.
54
What is the cardiac cycle?
The rhythmic contraction and relaxation of the heart muscles around 72 bpm in normal adults.
55
What are the three steps in the cardiac cycle?
1) Diastole - Heart muscles relax allowing blood to flow into all four chambers.
2) Atrial Systole and Ventricular Diastole - During systole, the hart muscles contract due to stimulation from the SA node. Blood moves into the ventricles.
3) Ventricular Systole and Atrial Diastole. AV node stimulates the ventricles to contract. Pumps blood out of the heart and into the aorta and pulmonary arteries.
56
What are the two major nodes in the heart and their functions?
The SA Node - The pacemaker of the heart that sends out electrical impulses that spread through the walls of both atria causing them to contract in unison.
The AV node - Allows for a 0.1 second pause that allows the atria to empty.
57
What causes a heart attack?
he clogging of the coronary arteries that bring oxygenated blood to the heart muscle.
58
What are the three types of blood cells?
1) Red Blood Cells - Most numerous type. Shaped like a disk with indentations. Responsible for binding O2 in the lungs and releasing it to body cells.
2) Platelets - Cellular Fragments that aid in blood clotting.
3) White Blood Cells - Make up less than 1% of all blood cells. Fight infections are part of the immune system.
59
What is the composition of blood?
1) 55% - Plasma
| 2) 45% - Cellular Elements (Red and White Blood Cells)
60
What is Plasma made of?
1) Water - 52%
| 2) Proteins electrolytes, and transported substances (3%)
61
What are the four blood types and how do they respond to other blood types?
1) A - Attacks blood with carbohydrate B.
2) B - Attacks blood with carbohydrate A.
3) AB - Immune System won't attack any red blood cells making it the universal recipient.
4) O - Does not Cause a Reaction Making it a Universal Donor.
62
How does blood clotting occur?
Platelets form a sticky plug that convert fibrinogen into fibrin that link to form a clot.
63
What are pathogens?
Disease causing viruses and micro-organisms.
64
What is the job of the immune system?
To protect the body against infectious diseases.
65
What are the external defenses against infections?
1) Hairs and Cilia - Filter out foreign particles and sweep them outward.
2) Mucous Membranes - Organ Systems exposed to the environment are lined by membranes that produce mucus to trap particles.
3) Stomach Acid - Gastric Acid kills most bacteria swallowed before it can enter the bloodstream.
4) Skin - Intact Skin forms a protective outer layer that virus and bacteria cannot penetrate.
5) Secretions - These fluids contain enzymes that prevent bacteria from multiplying (include, sweat, saliva, tears.)
66
What is the inflammatory response?
When nearby blood vessels widen and leak fluid into the site broken skin. White blood cells then engulf and destroy the bacteria.
67
What is the lymphatic system?
Consists of a branching network of fluid filled vessels and lymph nodes that fight an infection. Produces a large number of white blood cells when needed. Blood vessels carry the infection into the lymph fluid and sweep them into the lymph nodes where lymphocytes attack them.
68
What is specific immunity?
A preprogrammed response of white blood cells via previous exposure to the antigen.
69
What is an antigen?
A molecule that elicits and immune response.
70
What are the two types of lymphocytes?
1) B cells - Secrete antibodies, proteins that circulate in the blood for a specific antigen
2) T cells - Recognize antigens and then stimulate the production of either more T or B cells
71
What is clonal selection?
The response of activate lymphocytes to multiply and produce a large population to fight the received antigen.
72
What are memory cells?
The product of clonal selection that live for decades that allow for the memory cells to instigate an immune response to neutralize an invader before it can cause illness.
73
What causes allergies?
Sensitivities to allergens like protein molecules on pollen grains.
74
What are the two stages of an allergic reaction?
1) Sensitization Stage - Molecules of allergen mind to B cells with matching receptors. B cells secrete large amounts of antibodies to respond and some become embedded on the mast cells of these allergens that produce histamine that triggers and inflammatory response.
2) Second Exposure - If the same allergen enters the blood stream again. It will bind to the antibodies and cause the release of histamine which triggers the inflammatory response in tissues where the allergen enters.
75
What are autoimmune diseases?
Occur when the immune system improperly turns against one's own body molecules. Ex: Rheumatoid arthritis.
76
What are immunodeficiency Diseases?
Result from one or more components of the immune system being either missing or defective. AIDS and HIV are examples.
77
What is the purpose of the Endocrine System?
To make and secrete hormones.
78
What secretes and makes hormones?
Endocrine glands.
79
What are hormones?
Chemical signals that are transported around the body to communicate regulator messages.
80
What are all the parts of the Endocrine System?
1) Hypothalamus - Part of the brain that acts as the master control center and regulates the pituitary gland.
2) Pituitary Gland - Contained within a pocket of skull bone. Produces a wide variety of hormones to regulate many body functions.
3) Thyroid Gland - Helps Regulate Metabolism and Blood Calcium Levels.
4) Parathyroid Glands - Embedded in the Thyroid and Handle Specifically Blood Calcium Levels.
5) Pancreas - Regulates Blood Glucose Level Through the Secretion of Insulin and Glucagon.
6) Adrenal Glands - Sit atop each kidney and consist of two fused glands. (The Adrenal Medulla and Adrenal Cortex) Regulate Metabolism and the responses to stress.
7) Testes - In males affect growth and development and regulates sexual behavior and sperm production.
8) Ovaries - In females - affects growth and development and regulates reproductive cycles.
81
How do water soluble hormones work?
Bind to matching protein receptors on the outside of the cell. This is communicated to proteins in the cell's interior that brings about a change in the cell.
82
How do fat soluble hormones work?
Diffuse through the fatty cell membrane and bind to a receptor in the cytoplasm or nucleus. Interacts with the DNA to turn the genes on or off.
83
What are the two functions of the pancreas?
1) Digestive Enzyme Formation
| 2) Regulation of Blood Glucose Levels Through Insulin and Glucagon.
84
What is HGH?
Human Growth Hormone. Secreted by the Pituitary. Gigantism results from too much and dwarfism results from too little. Used by athletes attempting to build muscle mass.
85
What is osmoregulation?
The control of the gain or loss of water and dissolved ions.
86
What is the purpose of the urinary system?
Osmoregulation.
87
What are each of the elements of the human urinary system?
1) Kidneys - The central organs of the urinary system.
2) Ureter - Urine leaves each kidney via a tube called the ureter.
3) Renal Artery - Blood to be filtered enters each kidney via the renal artery.
4) Renal Vein - Filtered Blood leaves the kidney via a renal vein.
5) Urinary Bladder - Urine is stored in the urinary bladder until it is expelled
6) Urethra - A tube through which urine is expelled.
88
What is dialysis?
The filtration of the blood by a machine that acts as an artificial kidney. Requires 4-6 hours three times a week and must be continued for life.
89
What is a nephron?
The place where the actual filtering of blood and the formation of urine takes place.
90
What is the process for filtering blood and creating urine step by step?
1) Renal Artery Brings Blood Into the Kidney.
2) At the start of the nephron, blood pressure pushes water and dissolved molecules out of the blood through a filter and into the nephron tube.
3) Water and valuable solutes are reclaimed and returned to the bloodstream via tiny capillaries that surround the tubules. Unneeded substances are moved from the blood into the kidney via the same capillaries.
4) Blood returns to the bloodstream via the renal vein.
5) Concentrated urine travels through a connecting duct, exits the nephron via the ureter and is stored in the bladder until expelled.
91
What is urine made up of?
1) 94% - Water
2) 3% Urea - A Nitrogen Containing Waste Product.
3) 3% A Combination of Other Dissolved Solutes.
92
What are gonads?
The organs that produce gametes.
93
What are the male and female gametes?
Sperm and Egg respectively.
94
What are the male reproductive parts?
1) Prostate gland - Adds Fluid to Semen
2) Vas Deferens - Duct Through Which Sperm is Ejaculated and the Target of a Vasectomy.
3) Seminal Vesicles - Add Fluid to Semen.
4) Erectile Tissue - When Filled With Blood Produces and Erection
5) Epididymis - A tube in which semen is stored.
6) Urethra - Urine and sperm are conveyed through this tube.
7) Glans - The head of the penis where the sperm exit
8) Prepuce - Foreskin that covers the penis and can be removed via circumcision.
9) Testes - The male gonad where sperm are produced.
10) Scrotum - The external sac that holds the testes and keeps the slightly cooler than body temperature.
95
What happens during Spermatogenesis?
Diploid cells within the testes divide via meiosis to produce male gametes (Haploid sperm)
96
Describe the process of spermatogenesis step by step.
1) Cells near the outside of the seminiferous tubules divide by mitosis to produce diploid cells that are called primary spermatocytes.
2) Primary spermatocytes undergo meiosis I, producing two haploid secondary spermatocytes.
3) Each secondary spermatocyte undergoes meiosis II producing four haploid cells.
4) Each of these haploid cells develop into an immature sperm cell.
5) The sperm cells are pushed into the seminiferous tubule and then into the epididymis where they mature and are stored one developed.
97
What is the structure of a sperm?
1) Acrosome - A Membrane Enclosed Sac Containing Enzymes That help penetrate the egg.
2) Head - Contains a Haploid Nucleus with 23 Chromosomes.
3) Tail - Allows Movement.
98
What are the major parts of the female reproductive anatomy?
1) Ovary - The Female Gonad where eggs are produced and released
2) Oviduct - Also called the fallopian tube where egg meets the sperm.
3) Cervix - Narrow next at the bottom of the uterus.
4) Uterus - The site of pregnancy where the embryo develops into a baby.
5) Vagina - The birth canal where sperm enters and a baby exits
6) Urethra - A tube through which urine is excreted.
7) Vulva - Collective name for all the external female reproductive structures.
8) Clitoris - Contains erectile tissue that swells during arousal.
9) Labia Minora - A pair of skin folds that border the opening of the vagina.
10) Labia Majora - A pair of thick ridges that protect the underlying structures.
99
What is ovulation and when does it occur?
The release of an egg from the ovaries and occurs on day 14 of the approximately 28 day menstruation cycle.
100
What is oogenesis?
The development of a mature egg within the ovary.
101
What is a mature egg called?
An ovum.
102
Describe the cycle of oogenesis step by step.
1) Primary oocyte is a diploid cell that is paused in meiosis I. A hormone can trigger the dormant cell to complete its development.
2) A secondary oocyte is formed when a primary oocyte completes meiosis I and enters meiosis II.
3) Ovulation is the release of the secondary oocyte from the ovary into the oviduct. It will complete meiosis II to form a mature egg only if it contacts sperm in the oviduct.
4) The corpus luteum develops from the ruptured follicle. If the oocyte is not fertilized the corpus luteum degenerates.
103
What are all the steps of development from a single cell to a human baby?
1) Fertilization Occurs when the egg and sperm merge to form a single zygote.
2) The Zygote is then formed and switches into high metabolic gear to prepare for future growth.
3) Cleavage - About 36 hours after fertilization the zygote undergoes cleavage a series of rapid divisions that continues for several days. After fist cell division it becomes an embryo and remains about the size of the original egg.
4) Blastocyst - By day 7 it had begun to implant in the endometrium lining and consists of about 100 cells.
5) Gastrula - On day 9 cells migrate and order themselves into three main layers. Each of the layers of the resulting gastrula will develop into specific structures. Middle = heart, muscles, and other organs.
6) Embryo begins to develop early structures and has its own blood supply. Has the spinal chord beginning to form and is surrounded by the amnion with an umbilical chord connecting the embryo to the placenta.
7) First trimester - Organ Formation and fetus is now two inches long.
8) Second Trimester - Growth. Fetus grows and features become more distinct. At 20 weeks the fetus is about 8 inches long and can usually be felt moving.
9) Third Trimester - Fetus grows rapidly and develops the organs required to survive outside of the womb. Muscles grow and strengthen and it usually turns it head down as it fills the uterus.
10) Birth happens due to labor which induces the muscles that line the uterus to contact. The placenta is delivered afterwards.
104
What are the two main sections of the nervous system?
1) Central Nervous System - Receives incoming signals from the senses, integrates them to form a response, and transmits signals that produce reactions.
2) Peripheral Nervous System - Contains the Nerves that convey information into and out of the Central Nervous System.
105
What are the major parts of the Central Nervous System?
1) Meninges - Protection of a Layer of Connective Tissue.
2) Brain - Receives and Integrates sensory information, keeps the body functioning, controls the muscles, and is the center of emotion and intellect.
3) Spinal Chord - A Jellylike bundle of millions of nerve fibers protected inside the hard spine. The center of communication between the brain and the body.
4) Cerebrospinal Fluid - Fills the spaces in the brain and spine and provides a cushion, supply of nutrients, hormones and white blood cells.
106
What are the two systems contained within the Peripheral Nervous System?
1) Autonomic Nervous System - Controls many internal body organ systems such as the circulatory system and is largely unconscious.
2) Somatic Nervous System - Mostly under conscious control but also includes involuntary reflexes.
107
What are problems that can occur in the nervous system?
1) Depression
2) Alzheimer's Disease
3) Paralysis
4) Spinal Infections
108
What are the major parts of the brain?
1) Hypothalamus - Part of the endocrine system that controls the pituitary gland and regulates many body responses like the biological clock and hunger and thirst.
2) Cerebrum - The largest and most complex part of the brain. Consists of left and right hemispheres than control the opposite side of the body.
3) Cerebellum - Uses sensory information to plan an coordinate body movements.
4) Thalamus - Sorts and relays information to the Cerebrum
5) Brainstem - Receives integrates and passes on sensory information to other brain regions and helps control automatic functions like breathing and swallowing.
109
What are the major parts of the nervous system?
1) Cell Body - Central hub of a neuron that houses the nucleus and other organelles.
2) Dendrites - Usually numerous short and high branched. Receive signals from other neurons and convey them towards the cell body
3) Myelin Sheath - A Chain of Beadlike cells that support and insulate the axon and speed the electrical signal.
4) Axon - The extension from the cell body in full.
5) Vesicles - Filled with molecules of neurotransmitter that produce a response in the receiving cell.
6) Synapse - Junction were a neuron communicates with another cell across a narrow gap.
110
What are action potential and resistance potential?
Action potential - A temporary reversal of the electric charge caused by ions flowing into and out of the axon.
Resting Potential - The electrical charge difference of a neuron at rest.
111
How are senses conveyed to the brain?
Via electrical signals produced by the senses and sent to the brain.
112
How many bones are in the human body?
206.
113
What type of skeleton do human beings have?
An endoskeleton.
114
What is the structure of a bone?
Channels for blood vessels inside the bone
Red bone marrow produces blood cells.
Cartilage cushions joints and protects the ends of bones.
Connective tissue covers the outside of the bone and helps form new bone for growth or repair.
115
What are the three types of joints?
1) Ball and Socket - Arms and Legs with Rotation.
2) Hinge - Movement is allowed for in a single plane.
3) Suture joint - Doesn't mean movement. Provides flexibility to the skull. don't fully fuse until after birth
116
What are ligaments?
Strong fibrous connective tissue that holds bones together at the joints.
117
What make up muscle fibers?
Myofibril made from proteins and bundled together to form a muscle fiber.
118
What is a sarcomere?
The functional unit of contraction in a skeletal muscle fiber.
119
What are thin and thick filaments?>
Thin - Made from the protein actin
| Thick - Made from the Protein Myosin.
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Describe the process of muscle contraction step by step.
1) Myosin head attaches to the actin filament.
2) Myosin head bends - shortening the sarcomere by pulling the actin filament towards the center.
3) A molecule of ATP binds to the myosin head. causing it to detach from the actin filament.
4) The energy released by the breakdown of ATP causes the myosin filament to move to a high energy position where It can bind to the actin filament once again.
