Module 7: Human Systems -...
Transcript of Module 7: Human Systems -...
Module 7: Human Systems 7.00 Pretest Take the pretest before getting started. 7.01 Nervous and Endocrine Systems The nervous and endocrine systems are the two major systems of internal behavior in our bodies. They both send messages, although in different ways. The nervous system sends nerve impulses and electrical signals whereas the hormonal messages of the endocrine system are spread in a chemical nature. The Nervous System The nervous system is made up of a complex series of stimuli that send and process signals through the body. This communication sends and receives information that controls our senses, perceptions, thoughts and bodily reactions to situations. There are 2 main categories of the nervous system 1.
a. this system includes the CENTRAL NERVOUS SYSTEM and the PERIPHAL NERVOUS SYSTEM. Neurons Electrical signals called impulses are carried throughout the nervous system by specialized cells called nerve cells. Neurons share some common features:
Draw and label neuron here… Describe the following in 10 words or less.
Cell body the nucleuscontaining central part of a neuron exclusive of its axons and dendrites that is the major structural element of the gray matter of the brain and spinal cord, the ganglia, and the retina—called also perikaryon, soma. Dendrites a short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body. Axon also known as a nerve fibre, is a long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron's cell body. Axon Terminal the somewhat enlarged, often clubshaped endings by which axons make synaptic contacts with other nerve cells Nerve a whitish fiber or bundle of fibers that transmits impulses of sensation to the brain or spinal cord, and impulses from these to the muscles and organs.
Nervous System Form and Function
Neuron functions can be divided into 2 categories… 1sensory 2motor Sensory and motor neurons carry signals to and from the spinal cord and brain, while the communication neurons in the spinal cord and brain process received signals and send out new signals for the appropriate behavioral and bodily response. There are 3 types of nerons classified by the direction in which the impulses are traveling.
Type of neuron Description (in your own words)
Sensory These neurons tell the rest of the brain about the external and internal environment.
Interneurons a neuron that transmits impulses between other neurons, especially as part of a reflex arc
Motor Neurons Motor neurons contract muscles and mediate behavior, and other output neurons stimulate glands and organs.
The central nervous system is made up of the brain and spinal cord. This system processes the collected information, creating a response that is sent to the necessary part of the body. These 2 parts of the nervous system work together to allow the body to gather, send, process and respond to information. Central Nervous System The central nervous system (CNS) is made up of the ___________ and _________________, which serve as the main processing center for the entire nervous system. The Brain The brain is the body’s main control center, controlling bodily functions and responses. 10 9 8 7 6 5 4 3 2 1
Region of Brain Description (10 words max) Structure # (from above diagram)
Cerebrum the principal and most anterior part of the brain in vertebrates, located in the front area of the skull and consisting of two hemispheres, left and right, separated by a fissure
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Cerebellum the part of the brain at the back of the skull in vertebrates. Its function is to coordinate and regulate muscular activity
Cerebral cortex the outer layer of the cerebrum (the cerebral cortex ), composed of folded gray matter and playing an important role in consciousness. an outer layer of another organ or body part such as a kidney (the renal cortex ), the cerebellum, or a hair.
Corpus Callosum a broad band of nerve fibers joining the two hemispheres of the brain.
Temporal Lobe each of the paired lobes of the brain lying beneath the temples, including areas concerned with the understanding of speech.
Occipital Lobe the rearmost lobe in each cerebral hemisphere of the brain.
Parietal Lobe either of the paired lobes of the brain at the top of the head, including areas concerned with the reception and correlation of sensory information.
Frontal Lobe each of the paired lobes of the brain lying immediately behind the forehead, including areas concerned with behavior, learning, personality, and voluntary movement.
Pons the part of the brainstem that links the medulla oblongata and the thalamus.
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Thalamus xxx
either of two masses of gray matter lying between the cerebral hemispheres on either side of the third ventricle, relaying sensory information and acting as a center for pain perception.
Hypothalamus a region of the forebrain below the thalamus that coordinates both the autonomic nervous system and the activity of the pituitary, controlling body temperature, thirst, hunger, and other homeostatic systems, and involved in sleep and emotional activity.
Pituitary Gland the major endocrine gland. A peasized body attached to the base of the brain, the pituitary is important in controlling growth and development and the functioning of the other endocrine glands
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Medulla Oblongata
the continuation of the spinal cord within the skull, forming the lowest part of the brainstem and containing control centers for the heart and lungs.
Brain Stem the central trunk of the mammalian brain, consisting of the medulla oblongata, pons, and midbrain, and continuing downward to form the spinal cord.
The Spinal Cord The spinal cord is a cluster of neurons, fibers and associated tissue and other cells that run through the spinal canal and is connected to the all parts of the body to the brain. It serves as the main communication link between the brain and the rest of the body. There are 31 pairs of spinal nerves that branch off from the spinal cord. Although the main function of the spinal cord is to carry information to and from the brain, there are some reflex movements that are processed directly in the spinal cord. A reflex is a quick automatic response to a stimulus. **Remember that the veterbral column is the bone structure that surrounds and wraps around the spinal cord. Nervous System Controls The peripheral nervous system communicates between the CNS and the rest of the body. The 2 key parts are the: 1Sensory Nervous System
2Motor Nervous System. Peripheral Nervous System (PNS) All the neurons and related cells that carry signals to and from the spinal cord and brain Sensory nervous system Motor nervous system Nervous systems function to control responses to the organs and to coordinate the functions of the body and the communications among these parts. Somatic Nervous System Motor neurons of the somatic nervous system carry singals to muscles in response to changes in the external environment. This is typically under voluntary control. The rapid, automatic response is caused by a reflex arc. Steps of the reflex arc when stepping on a nail Sensory Receptors react to the sensation of the nail and send an impulse to the sensory neurons Information is passed to the spinal cord Interneuron in the spinal cord processes the info and immediately sends a message back (without ‘consulting’ the brain) the response neuron carries the message to the leg muscle At the same time that this reflex arc takes place, other impulses carry information about your injury to your brain as well, but that typically takes slightly longer. (Have you ever noticed that when you hurt yourself, sometimes you react before you really even ‘feel’ the pain? This is why!) *helpful tip ‘soma’ means body… this is our ‘body’ nervous system Autonomic Nervous System The autonomic nervous system regulates the body’s internal environment by controlling involuntary body activities of our muscles and organs. (for example, it will automatically speed up your heart rate when you start to run) There are 2 divisions: 1sympathetic nervous system 2parasympathetic nervous system
Division Sympathetic Parasympathetic
Purpose This division prepares the body for action by accelerating the heart, increasing metabolic rate, and other related effects that also require an increase in energy use.
Enhances activities that conserve or even gain energy
Effect Accelerating the heart; increasing metabolic rate; other related actions that also require an increase in energy use
This division helps the body recover and rest by stimulating digestion, slowing the heart, and
other related effects that decrease energy use.
*Review the nervous system diagram… place your cursor over each box for a quick summary. Endocrine System While the nervous system sends fast moving signals on direct paths through the body, the endocrine system sends slowly moving chemical signals. The endocrine system is made up of a series of glands. Endocrine glands release chemical messages called hormones into the blood stream. The hormone molecule can only be able to bind and act on cells that have chemical receptors to bind with that particular hormone. The body’s responses to hormones are usually SLOWER and longer lasting than the response to nerve impulses. The endocrine system uses opossing hormones to help maintain a healthy balance in the body. Example: the insulin hormone signals for the liver to convert glucose to glycogen for storage. The glucagon hormone signals the liver to convert glycogen to glucose to be rereleased into the blood stream as needed. *Complete the 7.01 Assessment (worksheet) 7.02 Respiratory and Circulatory The Respiratory and Circulatory Systems work together to carry OXYGEN to the body’s cells and to remove CARBON DYOXYDE from those cells. The main function of the respiratory system is to exchange these gases with the environment. The circulatory system transports the air between the respiratory system and other parts of the body. Respiratory System All cells in our body, especially our brain cells, require a constant supply of OXYGEN to undergo cellular respiration. The respiratory and circulatory systems provide our cells with oxygen needed for cellular respiration, while getting rid of the CARBON DIOXIDE produced by the same process. (Review the cellular respiration link if you want a quick reminder… or look back to your 2.05/2.06 assignments) A Label the parts and give a brief description of each.
Part Function/Description Letter of Location in Diagram Above
Diaphragm The diaphragm is a thin sheet of muscle that forms the bottom wall of the chest cavity. Contracting and relaxing this muscle helps to increase and decrease the volume of the
chest cavity, causing you to inhale and exhale. Although you can choose to hold your breath or change the rate of breathing for short periods of time, breathing is an involuntary, unconscious act controlled by the nervous system.
Larynx The larynx is found between the pharynx and trachea. It contains two highly elastic folds of tissue commonly called the vocal cords. As muscles pull these tissues together, the air moving between them causes the vocal cords to vibrate and produce sounds. This is how we are able to speak, shout, and sing.
Lungs and Bronchi
Air leaves the trachea and moves into two large tubes called bronchi. Each bronchus leads to one lung, where the tube divides into smaller bronchi that lead to even smaller passageways called bronchioles. The bronchi and bronchioles are surrounded by smooth muscles that contract and relax to regulate the size of the air passageways.
Nose The tissues inside your lungs are very delicate, so the main function of the nose is to filter, moisten, and warm the air as it enters the respiratory system. Hairs lining the entrance of the nasal cavity trap large particles, while the incoming air is warmed in the inner nasal cavity and sinuses. Mucus, the slimy substance secreted by mucus membranes, produced in these areas moistens the air while trapping smaller dust particles. You have observed this important filtering system firsthand if you've ever blown your nose after spending time in a dusty environment!
Pharynx Air moves from the nose into a cavity at the back of the mouth called the pharynx, or throat, which serves as a passageway for both air and food. Food and liquid leave the pharynx and enter the esophagus, while air travels into the trachea.
Trachea
Air moves from the pharynx into the trachea, sometimes called the windpipe. A flap of tissue called the epiglottis covers the entrance to the trachea when you swallow food or liquid to help ensure that they go into the esophagus instead. Mucus in the trachea continues to trap inhaled particles, while the cilia that line the trachea sweep the mucus and dust particles back toward the pharynx where they can be swallowed or spit out. This helps keep the lungs clean and clear to perform its important functions.
Circulatory System The circulatory system consists of the heart, blood, and blood vessles. 3 important functions: Delivers materials throughout the body, such as oxygen and various important nutrients. Removes waste from the body, such as carbon dioxide. Fights disease and seals cuts to prevent blood loss. The Heart The heart is a MUSCLE that works constantly. The contractions are the driving force behind the circulatory system, PUMPING blood through the blood vessels of the body. The heart is divided into 4 CHAMBERS, with a wall called a SEPTUM separating the right and left sides of the heart. The septum is important because it separates THE RIGHT SIDE FROM THE LEFT SIDE and prevents oxygenated and deoxygenated blood from mixing. Each side has an upper and lower chamber as well. The upper chambers are called THE ATRIA. The atria are the collecting areas into which blood flows from other areas of the body. The lower chambers, called VENTRICALS, pump blood out to somewhere else in the body. Label and describe the following parts of the heart: Aorta Pulmonary Artery Right Atrium Left Atrium Superior Vena Cava Pulmonary Vein Right Ventricle Left Ventricle Circulation Pulmonary Circulation Blood enters the heart through the right atrium, it then goes into the right ventricle to be pumped via the pulmonary artery to the lungs to be reoxygenated. After that it heads, via the pulmonary vein, to the left atrium in the heart to be pumped around the rest of the body again via the aorta. Substances transported to cells: oxygen, glucose, ions, proteins. substances transported from cells: Carbon dioxide, toxins excreted by the cells (to be filtered by the kidneys and excreted as urine) Systemic Circulation So once the blood rich in oxygen ( or oxygenated/oxygen rich) enters in to the Left side of the heart, it will be circulated throughout the body...So now the blood is rich in oxygen...this get absorbed maximally
in the body and CO2 is dumped off...this process continues and the deoxygenated blood returns back to the right side of the heart.. Just remember: Pulmonary = Lungs Systemic = Body *watch the video on the heart at the bottom of the page. Blood Vessels Blood moves through the circulatory system through 3 types of blood vessels:
Type of Blood Vessel Description (brief summary)
1 arteries
carry blood away from the heart main artery is the aorta
2 veins
are blood vessels that bring blood back to the heart
3 capillaries
carry blood away from the body and exchange nutrients waste and oxygen
Blood Blood is a mixture of several types of cells, ions, proteins, and water. The major components of blood are PLASMA which contains hormones, GLUCOSE, dissolved proteins, minerals and salts, RBC'S, white blood cells, and PLATELETS.
Blood Component Description (summary 10 words or less)
Plasma Plasma is a pale yellow sticky liquid. It makes up 55% of the blood’s volume.
Red Blood Cells a red blood cell that (in humans) is typically a biconcave disc without a nucleus. Erythrocytes contain the pigment hemoglobin, which imparts the red color to blood, and transport oxygen and carbon dioxide to and from the tissues.
White Blood Cells a colorless cell that circulates in the blood and body fluids and is involved in counteracting foreign substances and disease; a white (blood) cell. There are several types, all amoeboid cells with a nucleus, including lymphocytes, granulocytes, monocytes, and macrophages.
Platelets a small colorless diskshaped cell fragment without a nucleus, found in large numbers in blood and involved in clotting.
Blood Pressure As the heart pumps blood into the arteries, the flow of blood exerts pressure on the walls of the arteries, pushing the blood through the body. Sensory nerves in blood vessels send impulses to the brain. These impulses regulate blood pressure in a few ways: when blood pressure is HIGH, the nervous system signals the VASCULAR muscles in the blood vessel wall to relax so that the pressure will go down. when blood pressure is low, the nervous system signals for the muscles to TIGHTEN in order to increase the pressure. kidneys help regulate blood pressure by controlling the CONCENTRATION of blood. When blood pressure is high, hormones signal the kidneys to remove VITAMINS from the blood as urine (pee) so that the volume and pressure of blood will reduce. The number on the meter when the pressure is first released is the _____________________________, which is the force in the arteries when the heart pumps. The force in the arteries when the heart contracts in between pumps is called the _______________________________. A normal blood pressure reading is about: ___________ Cardiovascular Disease More than half of all the deaths in the US are related to _____________________________.
Disease Causes Symptoms Prevention Treatment
High Blood Pressure
Arterial Disease
Heart Attack
Stroke
**Complete the self check For your assignment, you need to find a creative way to describe how blood flows through the lungs, heart and body and how the respiratory system interacts with the circulatory system to deliver oxygen to our body cells. You could do this as a PowerPoint, comic strip, story, etc. Contact your teacher if you need help. 7.03 Digestive and Excretory Food
Molecules in food contain chemical energy that is used to produce _______, the molecule that powers a cell. Food (and water) also supply our cells with the materials needed to grow, divide, and repair. The digestive system is responsible for ____________________________ food into small molecules that can be used by the cells in your body. The excretory system eliminates _____________ from the body. Digestive system is made up of the digestive tract, which is a series of _____________ organs joined in a long twisting tube. Accessory organs help the body break down and _______________ food.
Organ Notes
Mouth (teeth, saliva)
Tongue
Pharynx
Esophagus
Stomach
Small Intestine
Large Intestine (E. coli)
Rectum and Anus
Accessory Organs
Organ Notes
Pancreas
Liver and Gallbladder
Appendix
Excretory System
Organ Notes
Skin
Lungs
Liver
Kidneys
Complete the self check… there is no assignment for this lesson. 7.04 Muscular, Skeletal, and Integumentary
The Skeletal System An organism’s skeletal system is made up of ______________ tissue with several important functions within the body.
Support
Protection
Movement
Mineral Storage
Blood Cell Formation
The human skeleton can be divided into 2 regions:
Made up of…
Axial Skeleton
Appendicular Skeleton
Bones are made up of different layers of tissue with different jobs. Explore the diagram and write a very brief (10 words or less) summary of the descriptions of each. (The descriptions are long, so just write a few words to remind yourself what each does)
Notes
Cartilage
Spongy Bone
Compact Bone
Bone Marrow
Periosteum
Osteoclast
Osteoblast
Joints A place where 2 bones meet is called a __________. All joints contain ________________________ tissue that holds bones together. 3 categories of joints:
Type Notes Example
Fixed/immovable
Slightly movable
Freely movable
Muscular System There are 3 different types of muscles
Type Notes
Skeletal
Smooth
Cardiac
Muscles of the Body Muscles are often grouped based on location and function within the body.
Muscle Group Where found
Quadriceps (‘quads’)
Pectoralis (‘pecs’)
Hamstrings
Latisimus dorsi
Gastrocnemius
Triceps
Trapezius
Biceps
Deltoids
Abdominals (‘abs’)
Muscle Movement Muscles produce movement by ____________________ (shortening) from end to end. Skeletal muscles are connected to ____________ by tough connective tissues called
_________________. This allows the muscle to pull on the bones. (like a lever and ______________) Most muscles work in opposing pairs… when one muscle contracts, the other ______________. Integumentary System The largest organ in our body is our ___________.
Role of Integumentary System
Description
Protection
Vitamin D Production
Gathering Information
Body Temperature
Excretion
Components of the Integumentary System
Component Notes
Skin
Hair
Nails
Glands
**In this assignment, you need to describe a task that you do in great detail, using what you’ve learned about the body so far. Choose something that you actually do to make it more interesting… a specific move in a sport you do (making a freepoint shot, doing a ballet move, throwing a football) or other activity (playing guitar, drawing, playing a video game). Think about what is involved… do you have to move your bones? How do your muscles help? How are your skin/hair/etc. involved? Consider including what we’ve learned about the nervous system, circulatory system, etc. too. You can present this through essay format, detailed labeled diagrams, PowerPoint, etc. Let your teacher know if you need help. 7.05 Reproductive System
The driving force behind many of the functions of the reproductive systems are hormones (_______________ and testosterone) Hormones are produced in the ________________, and they act on cells and tissues to produce many of the characteristics associated with males/females. In females, _________________ triggers breast development and the widening of hips. In males, the ___________________ causes growth of facial hair, increases muscular development and deepening of the voice. During ______________, the brain’s hypothalamus signals an increase in hormones that causes rapid growth and maturation. The reproductive system becomes fully functional. Male Reproductive System Remember that meiosis always produces ____________ sex cells (sperm for males) that contain a single set of chromosomes. This is important to ensure that when the gametes from both parents fuse together during __________________, the new zygote is a diploid cell with the full set of chromosomes. A sperm cell has a specialized structure for its voyage through the female reproductive system. The portion with the condensed ____________ is called the "head", which also contains ________________ to break through the egg cell’s thick outer layer. The midpiece of the sperm cell is packed with _____________releasing mitochondria to power the cell’s voyage. The tail section is called a _____________________ that moves back and forth to propel the sperm cell.
Structure Brief Description (10 words or less)
Vas Deferens
Epididymis
Testes
Urethra
Female Reproductive System The female reproductive system includes the organs and ducts involved in producing the ________ as well as those involved in housing and supporting a developing _____________.
Structure Brief Description
Fallopian Tube
Ovary
Vagina
All of the approximately 400,000 ______________ a woman will ever have are already formed at birth. After _______________, one (or possibly 2+) follicles mature and release its egg during
each monthly ______________________________________. Several hundred eggs will be released during a woman’s reproductive years. The menstrual cycle lasts an average of _________________. During the middle of the cycle, one (or sometimes 2+) egg develops and is released from the ovary in a process called ___________________. At the same time, hormones signal the __________________ to prepare to receive a fertilized egg. As a result, the walls of the uterus will __________________. The egg travels down the ________________________ over about 23 days. If it is not fertilized, the egg and the uterine lining will dissolve and are shed through _____________________. If the egg is fertilized by a sperm cell, the resulting ________________ will be imbedded in the wall of the ________ to receive nutrients and the menstrual cycle stops. Fertilization When sperm are released into the vagina, they swim through the __________ into the uterus and up into the __________________________. If an egg is present, it can be _________________. The sperm’s __________ nucleus fuses with the egg’s haploid nucleus to form one __________________ nucleus with the full ________ chromosomes. The fertilized egg is called a ________________ or an ________________.
Trimester What’s Happening?
1st Trimester fertilized egg undergoes _______________ until it becomes a
hollow ball of cells called a _____________________
implants into the wall of the ________________ where it will get
nutrients
cells begin to specialize
cells divide into 3 layers during ________________________
*Ectoderm becomes
____________________________________________
*Mesoderm becomes
___________________________________________
*Endoderm becomes
___________________________________________
Neural tube is formed during _________________________. (If
tube doesn’t close completely, this can cause a birth defect called
________________________ which can be prevented by
__________ acid in the diet.)
Membranes such as the amniotic sac and the placenta form to help
protect and _____________ the growing embryo.
After 8 weeks, the embryo is called a ______________
By the end of the 1st trimester most organs are formed although
they can’t function on their own. The fetus is about 8cm long and
can move and show signs of ______________.
2nd Trimester (your summary here)
3rd Trimester
(your summary here)
*Be sure to watch the video on embryonic development too.
Summary be sure you can describe the following processes in your own words…
Describe the path of sperm
Describe the path of the egg
Describe the main stages of development from fertilization to birth
7.06 Immune System
Nonspecific Defenses
__________________ are diseasecausing agents
Types of Pathogen Examples How they may be spread
Virus
Bacteria
Fungi
Protozoa
The first defense is a combination of physical and chemical barriers called
________________________.
Description/Examples
External
Internal Inflammatory response
White bood cells
Fever
Specific Defenses: The Immune System
This line of defense works together with the internal nonspecific defenses. The 2 main functions of
the immune system involve
production of proteins called ___________________
white blood cells called _______________________
Our body has unique chemical markers on it to help our immune system tell which cells are part of
our body and which are foreign invaders. When the immune system notices that an invader does
not have your body’s _______________________________, it will start to attack it.
Molecules called ________________ can be found on the outer surface of bacteria, viruses, etc.
When the immune system detects the antigens on the invading substance, it triggers an
__________________ response. Each antigen has a unique molecular ____________ that
stimulates production of a corresponding ___________________. The antibodies are specialized
______________ that bind to antigens (like puzzle pieces) that tells the body’s white blood cells
to attack.
The white blood cells involved in the specific defenses are mostly
__________________________ and ______________________________, which are both
produced in the red bone marrow.
The specific immune response can be divided into 2 main types of action: ________________
and ___________________________________ immunities.
Humoral Immunity
Activated when _________________ recognize and bind to _______________ on invading
pathogens
Bcells circulate through the blood stream, looking out for pathogens. Remember that B cells have
_________________ on them so they are looking for the pathogens that have antigens which
match their shape
Once the B cell’s antibody binds to the pathogen’s _______________, the T cells will tell the B
cell to grow and divide quickly, producing _________________ and ____________________
Plasma cells produce _________________ to go around the body and bind to any pathogen
antigens and signal to the body to attack and destroy the pathogens
Plasma cells die once the infection is gone, but the __________________________ remain. That
way, if the same pathogen ever comes back, the memory cells can respond more quickly.
CellMediated Immunity
Defends the body against invading pathogens that attack within body cells. Uses _____________
and does not involve _____________________.
When a body cell is invaded by a __________________, the cell’s membrane will show a part of
the pathogen’s ______________.
The circulating helper T cells detect the signal and start to ________________
All the new helper T cells activate cytotoxic T cells which destroy the pathogens and prevent the
infection from ___________________
The ____________ T cells made will stay in the body after the infection is gone so the body will
be able to respond faster if ever invaded by the same pathogen again.
**Be sure to review the Specific and Nonspecific Defenses in the chart on page 4
Active and Passive Immunity
The immune system uses _______________ cells to remember _____________ it has seen
before so that it can react against them more efficiently in the future. This is called
______________________ because it involves a response by a person’s own immune system.
Exposure to a pathogen through a _______________ results in an ____________________
active immunity. Vaccines allow a person to develop memory cells without encountering the
actual pathogen.
*Edward Jenner observed acquired immunity over 200 years ago when making observations
about milkmaids who were immune to getting _________________ because they once were
exposed to cowpox, a similar, but nondeadly disease.
Active Immunity Passive Immunity
Naturally Acquired
Artificially Acquired
Controlling Pathogens
Description
Antibiotics
Antivirals
Antiseptics (antimicrobials)
The misuse or overuse of __________________ has led to an increase in diseases that were
once considered under control. This is because many strains of bacteria have evolved a
resistance to the commonly used antibiotics, antiseptics, and medications.
The bacteria that are not killed by the exposure to the antiseptics or antibiotics survive to
__________________, producing an increasing population of bacteria with a
___________________ to those medications. (Can you say "Survival of the Fittest" aka "Natural
Selection"?!)
**Complete the handwashing lab to submit for 7.06. Let your teacher know if you have any
questions on your lab.