Chapter 1: Intro To The Human Body Flashcards
What is the definition of Anatomy?
Science of body structures and the relationships among them.
What is the definition of Physiology?
Science of body functions. How the body parts work.
What are the 6 levels of structural organization?
- Chemical
- Cellular
- Tissue
- Organ
- System
- Organismal
What is the chemical level of structural organization in the human body?
- Very basic level.
- Includes atoms (smallest units of matter that participate in chemical reactions).
- Includes molecules (2 or more atoms joined together).
What is the cellular level of structural organization in the human body?
- Molecules combine to form cells.
- Cells are smallest living units in human body.
What is the tissue level of structural organization in the human body?
- Tissues are group of cells and materials surrounding them that work together to perform a particular function.
4 basic types of tissues:
* Epithelial
* Connective
* Muscular
* Nervous
What is the organ level of structural organization in the human body?
- Different types of tissue work together.
- Organs are structures, composed of 2 or more different types of tissues.
- Have specific functions.
- Usually have recognizable shapes.
What is the system level of structural organization in the human body?
Consists of related organs with a common function (organ system).
What is the organismal level of structural organization in the human body?
- Any living individual.
- All parts of human body functioning together constitute the total organism.
What are the six important life processes of the human body?
- Metabolism
- Responsiveness
- Movement
- Growth
- Differentiation
- Reproduction
What is metabolism?
The sum of all chemical processes that occur in body.
Consists of 2 phases:
1. Catabolism (breakdown of complex chemical substances into simpler components).
2. Anabolism (building up of complex chemical substances from smaller, simpler components).
What is responsiveness?
- Body’s ability to detect and respond to changes.
- Different cells in body respond to changes in characteristic ways.
What is movement?
Motion of whole body, individual organs, single cells and tiny structures inside cells.
What is growth?
- Increase in body size that results from an increase in size of existing cells, an increase in number of cells, or both.
- Tissue sometimes increases in size because amount of material between cells increases.
What is differentiation?
- Development of a cell from an unspecialized to a specialized state.
- Precursor cells, can divide and give rise to cells that undergo differentiation, known as stem cells.
What is reproduction?
Refers to either:
1. Formation of new cells for tissue growth, repair or replacement. 2. Production of a new individual. Formation of new cells occurs through cell division.
What is homeostasis?
Maintenance of relatively stable conditions in body’s internal environment.
What is intracellular body fluid?
ICF refers to the fluid within cells.
What is extra-cellular body fluid?
- ECF refers to fluid outside body cells.
- ECF that fills the narrow spaces between cells of tissues is known as interstitial fluid.
What is an important aspect of homeostasis?
Maintaining the volume and composition of body fluids.
How is homeostasis disturbed?
- From external environment (ex: intense heat in summer).
- From internal environment (blood glucose level falls when skipping a meal).
- From psychological stresses in our social environment (demands of work/school).
How is homeostasis maintained?
Most often, nervous system and endocrine system, working together or independently, provide needed corrective measures.
How does the nervous system regulate homeostasis?
- Sending nerve impulses (action potentials) to organs, can counteract changes from balanced state.
- Nerve impulses cause rapid changes.
- Usually works through negative feedback system.
How does the endocrine system regulate homeostasis?
- Endocrine system includes glands, secrete messenger molecules (hormones) into blood.
- Hormones work slowly.
- Usually works through negative feedback system.
What are the 2 types of feedback systems?
Negative feedback system and positive feedback system.
What is a feedback system?
- Cycle of events, status of a body condition is monitored, evaluated, changed, remonitored, reevaluated.
- Each monitored variable is termed a controlled condition (controlled variable).
What is a stimulus in the feedback system?
Any disruption that changes a controlled condition.
What are the 3 basic components of a feedback system?
- A receptor.
- A control center.
- An effector.
What is a receptor in the feedback system?
- Body structure that monitors changes in a controlled condition and sends input to a control center.
- Is an afferent pathway (information flows toward control center).
- Typically, input is in the form of nerve impulses or chemical signals.
What is a control center in the feedback system?
- The brain. Sets the narrow range/set point within which controlled condition should be maintained.
- Evaluates input it receives from receptors.
- Generates output commands when they are needed.
What is output from the control center in the feedback system?
- Provides nerve impulses or chemical signals.
- Is an efferent pathway (information flows away from control center).
What is an effector in the feedback system?
- A body structure that receives output from the control center.
- Produces a response or effect that changes the controlled condition.
What is a negative feedback system?
- Reverses a change in a controlled condition.
- Regulates conditions in body that remain fairly stable over long periods.
- Example: High blood pressure.
What is a positive feedback system?
- Strengthens or reinforces a change in one of the body’s controlled conditions.
- Event outside the system must shut if off.
- Example: Normal childbirth or massive blood loss.
How does the negative feedback system regulate blood pressure?
Stimulus: Disrupts homeostasis by increasing BP.
Controlled Condition: Blood pressure.
Receptors: Baroreceptors in certain blood vessels.
Input: Nerve impulses.
Control Center: Brain.
Output: Nerve impulses.
Effectors: Heart and blood vessels.
Response: Decrease in HR, dilation of blood vessels cause BP to decrease. Return to homeostasis when response brings BP back to normal.
How does the positive feedback system regulate childbirth?
Stimulus: Contractions of the wall of uterus force baby’s head/body into cervix.
Controlled Condition: Stretching of the cervix.
Receptors: Stretch sensitive nerve cells in cervix.
Input: Nerve impulses.
Control Center: Brain.
Output: Brain interprets input, releases oxytocin.
Effectors: Muscles in wall of uterus. Contract more forcefully.
Response: Baby’s body stretches cervix more.
What is the anatomical position of the body?
- Subject stands erect facing the observer, head level and eyes facing directly forward.
- Lower limbs are parallel, feet are flat on floor, directed forward.
- Upper limbs are at sides with palm turned forward.
What is the prone position?
Body is lying facedown.
What is the supine position?
Body is lying faceup.
What are the regional names of the body?
- Head (Cephalic)
- Neck (Cervical)
- Trunk (Chest, abdomen and pelvis)
- Upper limbs
- Lower limbs
What does the Cephalic (head) region consist of?
- Cranial (skull).
- Facial (face).
- Frontal (forehead).
- Temporal (temple).
- Orbital or ocular (eye).
- Otic (ear).
- Buccal (cheek).
- Nasal (nose).
- Oral (mouth).
- Mental (chin).
- Occipital (base of skull).
What does the Trunk region consist of?
Thoracic (chest):
* Sternal (breastbone).
* Mammary (breast).
Abdominal (abdomen):
* Umbilical (naval).
* Coxal (hip).
Pelvic (pelvis):
* Inguinal (groin).
* Pubic (pubis).
* Perineal (region of anus and external genitals).
What does the upper limb region consist of?
- Axillary (armpit).
- Brachial (arm).
- Antecubital (front of elbow).
- Antebrachial (forearm).
- Carpal (wrist).
- Palmar or volar (palm).
- Dorsum (back of hand).
- Digital or phalangeal (fingers).
- Scapular (shoulder blade).
- Olecranal or Cubital (back of elbow).
- Manual (hand).
- Pollex (thumb).
What does the lower limb region consist of?
- Sacral (between hips).
- Gluteal (buttock).
- Popliteal (hollow behind knee).
- Sural (calf).
- Plantar (sole).
- Calcaneal (heel).
- Femoral (thigh).
- Patellar (anterior surface of knee).
- Crural (leg).
- Pedal (foot).
- Tarsal (ankle).
- Digital or Phalangeal (toes).
- Dorsum (top of foot).
- Hallux (great toe).
What does Superior directional term refer to?
- Toward the head, or upper part of a structure.
- Example: The heart is superior to the liver.
What does Inferior directional term refer to?
- Away from the head, or lower part of a structure.
- Example: The stomach is inferior to the lungs.
What does Anterior directional term refer to?
- Nearer to or at the front of the body.
- Example: The sternum (breastbone) is anterior to the heart.
What does Posterior directional term refer to?
- Nearer to or at the back of the body.
- Example: The esophagus (food tube) is posterior to the trachea (windpipe).
What does Medial directional term refer to?
- Nearer to the midline (imaginary vertical line that divides body into equal right and left sides).
- Example: The ulna is medial to the radius.
What does Lateral directional term refer to?
- Farther from the midline.
- Example: The lungs are lateral to the heart.
What does Intermediate directional term refer to?
- Between two structures.
- Example: The transverse colon is intermediate to the ascending and descending colons.
What does Ipsilateral directional term refer to?
- On the same side of the body as another structure.
- Example: The gallbladder and ascending colon are ipsilateral.
What does Contralateral directional term refer to?
- On the opposite side of the body from another structure.
- Example: The ascending and descending colons are contralateral.
What does Proximal directional term refer to?
- Nearer to the attachment of a limb to the trunk; nearer to the origination of a structure
- Example: The humerus (arm bone) is proximal to the radius.
What does Distal directional term refer to?
- Farther from the attachment of a limb to the trunk; farther from the origination of a structure.
- Example: The phalanges (finger bones) are distal to the carpals (wrist bones).
What does Superficial (External) directional term refer to?
- Toward or on the surface of the body.
- Example: The ribs are superficial to the lungs.
What does Deep (Internal) directional term refer to?
- Away from the surface of the body.
- Example: The ribs are deep to the skin of the chest and back.
What are the planes through the human body?
- Frontal.
- Transverse.
- Sagittal.
- Oblique planes.
What is a sagittal plane?
- Vertical plane that divides the body or an organ into right and left sides.
What is a midsagittal plane?
- When the plane passes through the midline of the body or an organ and divides it into equal right and left sides.
What is the midline?
- Imaginary vertical line that divides the body into equal left and right sides.
What is a parasagittal plane?
- When the sagittal plane does not pass through the midline, instead divides body or an organ into unequal right and left sides.
What is a frontal plane?
- Divides the body or an organ into anterior (front) and posterior (back) portions.
What is a transverse plane?
- Divides the body or an organ into superior (upper) and inferior (lower) portions.
- Can also be referred to as a cross-sectional or horizontal plane.
What is an oblique plane?
- Passes through the body or an organ at an oblique angle (any angle other than a 90-degree angle).
What is a section view?
- Is a cut of the body or one of its organs made along one of the planes just described.
What is a body cavity?
- Spaces that enclose internal organs.
- Bones, muscles, ligaments and other structures separate the various body cavities from one another.
What are the different body cavities?
- Cranial Cavity (includes vertebral canal).
- Thoracic Cavity (includes pleural cavity, pericardial cavity and mediastinum).
- Abdominopelvic Cavity (includes abdominal cavity and pelvic cavity).
What is the cranial cavity?
- Hollow space of the head, contains the brain.
- Bones of the vertebral column (backbone) form the vertebral canal which contains the spinal cord.
- 3 layers of protective tissue, the meninges and shock-absorbing fluid surround the brain and spinal cord.
What is the thoracic cavity?
- Formed by the ribs, the muscles in the chest, the sternum and thoracic portion of the vertebral column.
- Thoracic cavity contains the pericardial and pleural cavities and the mediastinum.
What is the pericardial cavity?
- Potential space between the layers of the pericardium that surrounds the heart.
What is the pleural cavity?
- Potential space between the layers of the pleura that surrounds a lung.
What is the mediastinum?
- Central portion of the thoracic cavity between the lungs; extends from the sternum to the vertebral column and from the first rib to the diaphragm.
- Contains the heart, thymus, esophagus, trachea and several large blood vessels.
- Contains all thoracic organs except the lungs themselves.
What is the abdominopelvic cavity?
- Extends from diaphragm to groin and is encircled by abdominal muscular wall and the bones and muscles of the pelvis.
- Divided into two portions, abdominal and pelvic cavity.
What is the abdominal cavity?
- Superior portion of the abdominopelvic cavity.
- Contains the stomach, spleen, liver, gallbladder, small intestine and most of the large intestine.
- The serous membrane is the peritoneum.
What is the pelvic cavity?
- Inferior portion of the abdominopelvic cavity.
- Contains urinary bladder, portions of large intestine and internal organs of reproductive organs.
- Organs inside the thoracic and abdominopelvic cavities are called viscera.
What is a membrane?
- Thin, pliable tissue that covers, lines, partitions, or connects structures.
What is a serous membrane?
- Slippery, double-layered membrane associated with body cavities that does not open directly to the exterior.
- Covers the viscera within the thoracic and abdominal cavities and lines the walls of the thorax and abdomen.
Consists of 2 parts:
* Parietal layer.
* Visceral layer.
What is the pleura?
- Serous membrane of the pleural cavities.
- Visceral pleura clings to surface of lungs.
- Parietal pleura lines the chest wall, covering the superior surface of the diaphragm.
What is the pericardium?
- The serous membrane of the pericardial cavity.
- Visceral pericardium covers the surface of the heart.
- Parietal pericardium lines the chest wall.
What is the peritoneum?
- The serous membrane of the abdominal cavity.
- Visceral peritoneum covers the abdominal viscera.
- Parietal peritoneum lines the abdominal wall, covering the inferior surface of the diaphragm.
- Surrounds most of the abdominal organs.
What is retroperitoneal?
- Abdominal organs that are not surrounded by the peritoneum; instead they are posterior to it.
- Kidneys, adrenal glands, pancreas, duodenum of small intestine, ascending and descending colons of large intestine, and portions of the abdominal aorta and inferior vena cava are retroperitoneal.
What are the 9 abdominopelvic regions?
- Right hypochondriac.
- Epigastric.
- Left hypochondriac.
- Right lumbar.
- Umbilical.
- Left lumbar.
- Right inguinal.
- Hypogastric.
- Left inguinal.
What are the 4 abdominopelvic quadrants?
- Right upper quadrant.
- Left upper quadrant.
- Right lower quadrant.
- Left lower quadrant.
