CH.1 : AN INTRODUCTION TO THE HUMAN BODY Flashcards
What is homeostasis?
the state of relative stability of the body’s internal environment.
What are the two branches of science? Explain them.
- anatomy the science of body structures and the relationships among them
- physiology is the science of body functions—how the body parts work.
What are the smallest units of matter that participate in chemical reactions?
atoms
What are molecules made up of?
two or more atoms joined together
What atoms are essential for maintaining life?
carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), calcium (Ca), and sulfur (S)
Molecules combine to form ___
cells
What are tissues made up of ?
groups of cells and the materials surrounding them that work together to perform a particular function
At the ___ level different types of tissues are joined together.
organ
A system consists of?
related organs with a common function.
Give an example of a body system and explain it:
digestive system, which breaks down and absorbs food.
What is an organism?
- any living individual.
- All the parts of the human body functioning together constitute the total organism.
What is palpation?
the examiner feels body surfaces with the hands.
What is auscultation?
the examiner listens to body sounds to evaluate the functioning of certain organs, often using a stethoscope to amplify the sounds.
What is percussion?
the examiner taps on the body surface with the fingertips and listens to the resulting echo.
What are the six most important life processes of the human body?
metabolism, responsiveness, movement, growth, differentiation and reproduction
In terms of the six most important life processes, explain metabolism and give an example.
- the sum of all the chemical processes that occur in the body
- One phase is catabolism, the breakdown of complex chemical substances into simpler components.
- other phase is anabolism, the building up of complex chemical substances from smaller, simpler components.
- For ex, digestive processes catabolize (split) proteins in food into amino acids. These amino acids are then used to anabolize (build) new proteins that make up body structures such as muscles and bones.
In terms of the six most important life processes, explain responsiveness and give an example.
- the body’s ability to detect and respond to changes
- For example, an increase in body temperature during a fever represents a change in the internal environment
In terms of the six most important life processes, explain movement and give an example.
- includes motion of the whole body, individual organs, single cells, and even tiny structures inside cells.
- For example, the coordinated action of leg muscles moves your whole body from one place to another when you walk or run.
In terms of the six most important life processes, explain growth and give an example.
- an increase in body size that results from an increase in the size of existing cells, an increase in the number of cells, or both.
- for example, mineral deposits accumulate between bone cells, causing the bone to grow in length and width
In terms of the six most important life processes, explain differentiation and give an example.
- the development of a cell from an unspecialized to a specialized state. (stem cells)
- For example, red blood cells and several types of white blood cells all arise from the same unspecialized pre- cursor cells in red bone marrow.
In terms of the six most important life processes, explain reproduction.
-refers either to (1) the formation of new cells for tissue growth, repair, or replacement, or (2) the production of a new individual.
In terms of the six most important life processes, explain reproduction.
-refers either to (1) the formation of new cells for tissue growth, repair, or replacement, or (2) the production of a new individual.
Discuss the importance of body fluids and which one is considered to be the body’s internal environment.
- they control the transportation of substances into and out of cells.
- Intracellular fluid is the fluid within the cells of the body
- extracellular fluid is the fluid outside the body cells.
- The extracellular fluid that takes up the areas between tissue cells is called interstitial fluid, which is considered to be the body’s internal environment.
ECF differs depending on where it occurs in the body: ECF within blood vessels is termed ___ _____, within lymphatic vessels it is called ___, in and around the brain and spinal cord it is known as ___ fluid , in joints it is referred to as____ fluid, and the ECF of the eyes is called ___ ___ and vitreous body.
- blood plasma
- lymph
- cerebrospinal fluid
- synovial
- aqueous humor
The composition of interstitial fluid changes as substances move back and forth between it and blood plasma. Such exchange of materials occurs across the thin walls of the smallest blood vessels in the body which are?
the blood capillaries
What is a feedback system/feedback loop?
- is a cycle of events in which the status of a body condition is monitored, evaluated, changed, remonitored, reevaluated, and so on.
- Each monitored variable is termed a controlled condition
- Any disruption that changes a controlled condition is called a stimulus
What is a feedback system/feedback loop?
is a cycle of events in which the status of a body condition is monitored, evaluated, changed, remonitored, reevaluated, and so on.
In terms of a feedback system, explain the receptor.
-monitor changes in a controlled condition and send input to a control center (afferent pathway).
In terms of a feedback system, explain the control centre.
-sets the value (set point) at which a controlled condition should be maintained, evaluates the input it receives from receptors (efferent pathway), and generates output commands when they are needed
In terms of a feedback system, explain the effector.
- Effectors receive out- put from the control center and produce a response (effect) that alters the controlled condition.
What does a negative feedback system do? Give an example
- reverses a change in a controlled condition.
- regulation of blood pressure
What does a positive feedback system do ? Give an example
- tends to strengthen or reinforce a change in one of the body’s controlled conditions.
- childbirth
What is a disorder?
any abnormality of structure or function
What is epidemiology?
The science that deals with why, when, and where diseases occur and how they are transmitted among individuals in a community
What is the anatomical position?
Descriptions of any region or part of the human body assume that it is in a standard position of reference
If the body is lying face down, it is in the ___ position
prone
If the body is lying face up, it is in the ___ position.
supine
The trunk of the body consists of the __, ___, and ___.
chest, abdomen and pelvis
Each upper limb attaches to the trunk and consists of? (6)
shoulder, armpit, arm, forearm, wrist and hand
Each lower limb also attaches to the trunk and consists of? (5)
buttock, thigh, leg, ankle and foot
superior means toward the __ part of the body, and inferior means toward the ___ part of the body.
upper, lower
intermediate:
between two structures
proximal:
distal:
- near the attachment of a limb to the trunk
- farther from the attachment of a limb to the trunk
superficial:
deep:
- toward the surface of the body
- away from the surface of the body
planes:
imaginary flat surfaces that pass through the body parts
sagittal plane:
a vertical plane that divides the body or an organ into right and left sides.
A frontal or coronal plane :
divides the body or an organ into anterior (front) and posterior (back) portions.
transverse plane :
divides the body or an organ into superior (upper) and inferior (lower) portions.
What are body cavities?
spaces within the body that help protect, separate, and support internal organs.
What separates body cavities from one another?
Bones, muscles, ligaments, and other structures
Describe the cranial cavity:
- a hollow space of the head formed by cranial bones
- contains the brain
Describe the vertebral (spinal) canal:
- formed by the bones of the vertebral column (backbone)
- contains the spinal cord.
What surrounds the brain and spinal cord?
-Three layers of protective tissue (the meninges) and a shock-absorbing fluid
What are the major body cavities of the trunk?
-the thoracic and abdominopelvic cavities.
What forms the thoracic cavity?
-the ribs, the muscles of the chest, the sternum (breastbone), and the thoracic portion of the vertebral column.
Within the thoracic cavity, are the ___ cavity, the ____ cavities and the ____
pericardial, pleural, mediastinum
Explain the pericardial cavity in the thoracic cavity.
a fluid-filled space that surrounds the heart
Explain the pleural cavities in the thoracic cavity.
two fluid-filled spaces, one around each lung
Explain the mediastinum in the thoracic cavity.
- anatomical region in the central part of the thoracic cavity
- It is between the lungs, extending from the sternum to the vertebral column and from the first rib to the diaphragm
- contains all thoracic organs except the lungs themselves.
What is the diaphragm?
dome-shaped muscle that separates the thoracic cavity from the abdominopelvic cavity.
What forms the abdominopelvic cavity?
-extends from the diaphragm to the groin and is encircled by the abdominal muscular wall and the bones and muscles of the pelvis.
The abdominopelvic cavity is divided into two portions, even though no wall separates them. What are the two sections and explain them.
- The superior portion, the abdominal cavity contains the stomach, spleen, liver, gallbladder, small intestine, and most of the large intestine.
- The inferior portion, the pelvic cavity contains the urinary bladder, portions of the large intestine, and internal organs of the reproductive system.
What is the name of the organs found inside the thoracic and abdominopelvic cavities?
viscera
What does the serous membrane cover and line?
-the viscera within the thoracic and abdominal cavities and also lines the walls of the thorax and abdomen.
Name the parts of serous membrane and explain them.
- parietal layer : a thin epithelium that lines the walls of the cavities
- visceral layer: a thin epithelium that covers and adheres to the viscera within the cavities
The serous membrane of the pleural cavities is called the ___
pleura
The serous membrane of the pericardial cavity is the ____
pericardium
The _____ is the serous membrane of the abdominal cavity.
peritoneum
The names of the nine abdominopelvic regions are :
right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical left lumbar, right inguinal (iliac), hypogastric (pubic), and left inguinal (iliac).
The names of the abdominopelvic quadrants are :
right upper quadrant (RUQ), left upper quadrant (LUQ), right lower quadrant (RLQ), and left lower quadrant (LLQ).
The human body consists of six levels of structural organization, name them in order:
chemical, cellular, tissue, organ, system, and organismal.
Which two body systems regulate homeostasis and how?
- nervous system detects body changes and sends nerve impulses to counteract changes in controlled conditions.
- The endocrine system regulates homeostasis by secreting hormones.
