Title: The Human Body
1 2The Human Body
- There are over 100 trillion cells in your body.
Those cells are organized into tissues.
Different tissues are organized into organs.
Groups of organs make organ systems. Organ
systems make up an organism.
3There are four basic types of tissues
__________ tissue - protects
4There are four basic types of tissues
Epithelial tissue - protects
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6One kind of epithelial tissue is the skin.
Epithelial tissue also lines the gut and lungs.
Many glands are made of epithelial tissue.
7There are four basic types of tissues
__________ tissue supports and defends
8There are four basic types of tissues
Connective tissue - supports and defends
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10Connective Tissue supports and defends.
- Cells of the immune system Macrophages and
lymphocytes
11Connective Tissue supports and defends.
- Cells of the skeletal system fibroblasts,
cartilage, bone
12Connective Tissue supports and defends.
- Adipose tissue (fat) , Erythrocytes (red blood
cells)
13There are four basic types of tissues
__________ tissue sends signals
14There are four basic types of tissues
Nervous tissue - sends signals
15Nervous tissue sends signals.
- Made up of neurons and support cells (also called
glial cells)
16There are four basic types of tissues
__________ tissue permits movement
17There are four basic types of tissues
Muscle tissue - permits movement
18Muscle tissue permits movement.
- There are three types of muscle tissue smooth,
skeletal and cardiac.
19Homeostasis- the maintenance of a stable internal
environment
20The body fluid not inside your cells is called
extracellular fluid.
21Because so much exchange occurs across the
membranes of cells, extreme changes in the
composition or volume of the extracellular fluid
can have very serious effects on the cells.
22To maintain homeostasis, the central nervous
system gathers information about what is going on
in the body, evaluates this feedback, and issues
commands to counteract any change from normal.
23Most things are controlled by _________
__________.
24Most things are controlled by negative feedback.
25Things such as blood pressure, body temperature
and pH are compared with their normal values.
26Anything that causes a change away from the
normal value initiates a response from the body
that brings it back to normal.
27An example of negative feedback The normal body
temperature is about 98 degrees Fahrenheit. When
you have a fever, your body temperature is above
this normal level, and the nervous system detects
this change.
28The brain will then trigger mechanisms such as
sweating and dilating the blood vessels in the
skin, which lower your temperature back to normal.
29Some things in the body are controlled by
_________ __________, which causes the body to
drive the variable even farther away form normal.
30Some things in the body are controlled by
positive feedback, which causes the body to drive
the variable even farther away form normal.
31This happens in childbirth the pressure of the
babys head on the lower part of the uterus
increases the frequency and intensity of uterine
contractions.
32The Skeletal System
33There are __________ bones in the adult skeleton.
34There are 206 bones in the adult skeleton.
35Skeletal System
- A flexible endoskeleton allows the body a wide
range of motion while supporting a body of
considerable size. - The skeletal system provides a frame work against
which the muscles can pull. - It also protects the delicate organs inside the
body, such as the brain, lungs, heart. Etc.
36The human skeleton has two main parts__________
skeleton skull, ribcage, backbone__________
skeleton arms, legs, shoulders, pelvis,etc.
37The human skeleton has two main partsAxial
skeleton skull, ribcage, backbone__________
skeleton arms, legs, shoulders, pelvis,etc.
38The human skeleton has two main partsAxial
skeleton skull, ribcage, backboneAppendicular
skeleton arms, legs, shoulders, pelvis,etc.
39Type of Bones
Flat ribs, shoulder
40Type of Bones
Long arms, legs
41Type of Bones
Short feet, wrists
42Type of Bones
Irregular vertebrae
43- Bone is made of calcium-hardened fibers that make
it strong yet flexible. It is a living tissue
and receives oxygen and nutrients by blood
vessels that pass through hollow channels in the
bone called ______________________________. - Bones also contain nerve fibers. Bones are
surrounded by a tough white membrane called the
________________. - Bone tissue can either be in the form of compact
bone or spongy bone.
44- Bone is made of calcium-hardened fibers that make
it strong yet flexible. It is a living tissue
and receives oxygen and nutrients by blood
vessels that pass through hollow channels in the
bone called Haversion canal. - Bones also contain nerve fibers. Bones are
surrounded by a tough white membrane called the
________________. - Bone tissue can either be in the form of compact
bone or spongy bone.
45- Bone is made of calcium-hardened fibers that make
it strong yet flexible. It is a living tissue
and receives oxygen and nutrients by blood
vessels that pass through hollow channels in the
bone called Haversion canal. - Bones also contain nerve fibers. Bones are
surrounded by a tough white membrane called the
periosteum. - Bone tissue can either be in the form of compact
bone or spongy bone.
46Haversion canals
47Two substances that can be found inside bone
- ___________ marrow produces red blood cells.
- ___________ marrow stores fat.
48Two substances that can be found inside bone
- Red marrow produces red blood cells.
- Yellow marrow stores fat.
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50- ____________ is a type of connective tissue that
is softer and more flexible than bone. It is the
main component of embryonic skeletons. During
development, much of it hardens into bone. In
adults, cartilage can still be found in the ear,
nose, trachea, and at the end of bones to keep
them from grinding against each other.
51- Cartilage is a type of connective tissue that is
softer and more flexible than bone. It is the
main component of embryonic skeletons. During
development, much of it hardens into bone. In
adults, cartilage can still be found in the ear,
nose, trachea, and at the end of bones to keep
them from grinding against each other.
52__________ - bone tissue is broken down faster
than it is replaced. Bones become less dense and
brittle. Osteoporosis occurs primarily in
females due to the loss of calcium and sex
hormones during menopause.
53Osteoporosis - bone tissue is broken down faster
than it is replaced. Bones become less dense and
brittle. Osteoporosis occurs primarily in
females due to the loss of calcium and sex
hormones during menopause.
54- A __________ is the place at which two bones
meet. They can either be immovable (skull),
slightly moveable (vertebrae), or freely moveable
(knee).
55- A joint is the place at which two bones meet.
They can either be immovable (skull), slightly
moveable (vertebrae), or freely moveable (knee).
56Immoveable joints (sutures)
57Slightly moveable (vertebrae)
58Freely moveable - (knee)
59- _____________ - connect bone to bone
- ____________ - connect bone to muscle
60Ligaments connect bone to bone
Tendons connect bone to muscle
61Muscular System
http//srs.dl.ac.uk/OTHER/OW/MUSCLE/page2.html
62There are three kinds of muscles
- ____________ - Appears striated,
- voluntary movement
- ____________ - Walls of internal organs such as
the stomach and blood vessels, involuntary
movement - ____________ - Only in the heart, appears
striated, involuntary
63There are three kinds of muscles
- Skeletal - Appears striated,
- voluntary movement
- ____________ Walls of internal organs such as the
stomach and blood vessels, involuntary movement - ____________ Only in the heart, appears striated,
involuntary
64There are three kinds of muscles
- Skeletal - Appears striated,
- voluntary movement
- Smooth - Walls of internal organs such as the
stomach and blood vessels, involuntary movement - ____________ Only in the heart, appears striated,
involuntary
65There are three kinds of muscles
- Skeletal - Appears striated,
- voluntary movement
- Smooth - Walls of internal organs such as the
stomach and blood vessels, involuntary movement - Cardiac - Only in the heart, appears striated,
involuntary
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68- The skeleton provides a framework against which
the muscles can pull. One end of the muscle, the
_______, is attached to a bone that remains
stationary during the contraction. The other end
of the muscle, the _____________, is attached to
a bone that moves during the contraction.
69- The skeleton provides a framework against which
the muscles can pull. One end of the muscle, the
origin is attached to a bone that remains
stationary during the contraction. The other end
of the muscle, the _____________, is attached to
a bone that moves during the contraction.
70- The skeleton provides a framework against which
the muscles can pull. One end of the muscle, the
origin is attached to a bone that remains
stationary during the contraction. The other end
of the muscle, the insertion, is attached to a
bone that moves during the contraction.
71_____________ cause the limbs to straighten
- _____________ cause the limbs to bend at a joint
72Extensors cause the limbs to straighten
Flexors cause the limbs to bend at a joint
73- Within each muscle are bundles of smaller muscle
fibers called myofibrils. Those myofibrils
contain many protein filaments called ________
and __________. - Actin and myosin filaments are arranged into
sacromeres, which are the functional unit of
contractions.
74- Within each muscle are bundles of smaller muscle
fibers called myofibrils. Those myofibrils
contain many protein filaments called actin and
myosin - Actin and myosin filaments are arranged into
sacromeres, which are the functional unit of
contractions.
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76- When a muscle fiber contracts, adjacent myosin
and actin filaments slide along one another so
that they overlap a great deal and shorten each
sarcomere. This explanation of muscle
contraction is called the _____________________
theory.
77- When a muscle fiber contracts, adjacent myosin
and actin filaments slide along one another so
that they overlap a great deal and shorten each
sarcomere. This explanation of muscle
contraction is called the Sliding filament theory.
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80The Skin
- (The Integumentary System)
81The Skin
- Skin protects the body from injury, provides
defense against disease, helps regulate
temperature, and prevents the body from drying
out.
82The Skin
- The skin is composed of three layers
- __________-outermost layer of skin these skin
cells are dead and are continually being replaced - __________-middle layer has many nerve ending,
blood vessels, hair follicles and sweat glands - __________ __________-inner layer stores fat,
provides insulation
83The Skin
- The skin is composed of three layers
- Epidermis-outermost layer of skin these skin
cells are dead and are continually being replaced - __________-middle layer has many nerve ending,
blood vessels, hair follicles and sweat glands - __________ __________-inner layer stores fat,
provides insulation
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85The Skin
- The skin is composed of three layers
- Epidermis-outermost layer of skin these skin
cells are dead and are continually being replaced - Dermis-middle layer has many nerve ending, blood
vessels, hair follicles and sweat glands - __________ __________-inner layer stores fat,
provides insulation
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87The Skin
- The skin is composed of three layers
- Epidermis-outermost layer of skin these skin
cells are dead and are continually being replaced - Dermis-middle layer has many nerve ending, blood
vesse bfhls, hair follicles and sweat glands - Subcutaneous tissue-inner layer stores fat,
provides insulation
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89Some skin disorders
A basal cell carcinoma is a form of skin cancer.
90Some skin disorders
For reasons no one completely understands,
follicles, often called pores, sometimes get
blocked. Sebum (oil) which normally drains to the
surface gets blocked and bacteria begins to grow.
91Some skin disorders
Malignant melanoma is a cancer which usually
starts in the skin, either in a mole or in
normal-looking skin. Although the number of
people who develop melanoma is rising, it is
still an uncommon type of cancer.
92Some skin disorders
Psoriasis is an immune-mediated, genetic disease
manifesting in the skin and/or the joints. It is
a non-contagious and life-long skin disease that
has different forms. Some people may have a spot
or two, while others may have extensive coverage
on their body.
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94Immune System
95Immune System
The skin and mucous membranes provide the first
line of defense.
96Immune System
The second line of defense is provided by several
different patrolling cells
97__________ kill bacteria one at a time by
ingesting them
98Macrophages kill bacteria one at a time by
ingesting them
99__________ release chemicals that kill nearby
bacteria (and themselves)
100Neutrophils release chemicals that kill nearby
bacteria (and themselves)
101The inflammatory response expansion of blood
vessels at site of injury (causing swelling and
redness) Migration of macrophages and neutrophils
102The temperature response fevers inhibit
bacterial growth
103Immune System
The third line of defense is the IMMUNE SYSTEM!!!!
104Macrophages initiate the immune defense by
sending an alarm signal
105Helper T cells activate killer T cells and B
cells
106Killer T cells attack and kill infected body
cell
107B cells use antibodies to label invaders for
destruction by macrophages and killer T cell
some become _________cells
108B cells use antibodies to label invaders for
destruction by macrophages and killer T cell
some become memory cells
109Autoimmune diseases
In autoimmune diseases, the body cannot
distinguish normal body cells from foreign
invaders, and the body attacks its own cells
110Prominent autoimmune diseases afflicting 22
million people in the US, costing more than 100
billion annually to treat
111Allergies are caused by an immune response to a
harmless substance.
112HIV attacks and cripples the immune system by
destroying the white blood cells.
113Endocrine System
114Endocrine System
The endocrine organs secrete _______ Into the
blood stream
115Endocrine System
The endocrine organs secrete hormones into the
blood stream
116Endocrine System
Pineal Gland secretes the hormone
Melatonin-circadian rhythms
117Endocrine System
Pituitary Gland secretes the hormones
- Vasopressin-water reabsorption
- Oxytocin-uterine contractions during labor
118Endocrine System
Pituitary Gland secretes the hormones
- Growth hormone-bone and muscle growth
- Prolactin-milk production
119Endocrine System
Thyroid secretes the hormones
- Thyroid hormones (T4 T3)-metabolic activity
- Calcitonin-decreases blood calcium level
120Endocrine System
Parathyroid secretes the hormone
- Parathyroid hormone-increases blood calcium
121Endocrine System
Adrenal- secretes the hormone
- Epinephrine-increases heart rate
122Endocrine System
Pancreas- secretes the hormones
- Insulin-lowers blood glucose
- Glucagon-increases blood glucose
123Endocrine System
Ovary- secretes the hormones
- Estrogen-female characteristics
- Progesterone-maintenance of endometrium
124Endocrine System
Testis- secretes the hormone
- Testosterone-male characteristics
125Reproductive System
126Males The male gonads, called the __________,
contain two components the seminiferous tubules
and the interstitial cells.
127Males The male gonads, called the testes,
contain two components the seminiferous tubules
and the interstitial cells.
128Sperm are produced in the seminiferous tubules,
while the interstitial cells secrete testosterone
and other hormones.
129The testes are located in an external pouch
called the scrotum, which maintains a temperature
2-4oC lower than the body temperature, a
condition essential for sperm survival.
Scrotum
130Sperm pass from the seminiferous tubule
131Sperm pass from the seminiferous tubule into the
epididymis
132Sperm pass from the seminiferous tubule into the
epididymis then the vas deferens
133Sperm pass from the seminiferous tubule into the
epididymis then the vas deferens and then to the
urethra
134Sperm pass from the seminiferous tubule into the
epididymis then the vas deferens and then to the
urethra and out through the penis. Puberty is
between 13-15 years old.
135Females The female gonads, called the _______,
produces eggs and secrete the hormones estrogen
and progesterone.
136Females The female gonads, called the ovaries,
produces eggs and secrete the hormones estrogen
and progesterone.
137Once a month, an immature egg is released from
the ovary into the abdominal cavity and drawn
into the fallopian tube.
138The egg then travels to the __________ , which is
the site of fetal development.
139The egg then travels to the uterus , which is the
site of fetal development.
140The lower end of the uterus is called the cervix,
which is connected to the vagina. Puberty is
complete by age 13.
cervix
141During ovulation, the wall of the uterus thickens
to prepare for pregnancy. If the egg is not
fertilized by a sperm, then this thickened layer
is shed and blood vessels are broken, which is
called menstruation.
142Human Development
143The fusion of a sperm and egg is called a
__________.
144The fusion of a sperm and egg is called a zygote.
145After fertilization the zygote rapidly divides
into more cells and continues to travel down the
fallopian tube.
146Around the sixth day after fertilization, the
embryo implants in the tissue of the uterus.
147The growing fetus receives oxygen and nutrients
directly from its mother through the __________
and umbilical cord.
148The growing fetus receives oxygen and nutrients
directly from its mother through the placenta and
umbilical cord.
149Circulatory System
150The circulatory system transports nutrients,
wastes, oxygen, carbon dioxide and hormones.
151It also distributes heat and maintains body
temperature.
152The circulatory system is composed of blood
vessels, lymphatic vessels, blood and the heart.
153Blood leaves the heart through __________, which
branch into many smaller arterioles, and then to
capillaries.
154Blood leaves the heart through arteries, which
branch into many smaller arterioles, and then to
capillaries.
155In the capillaries, food and oxygen are
transferred from the blood to the body cells, and
carbon dioxide and wastes are picked up and
carried away.
156Blood returns to the heart through venules and
veins.
157The cardiovascular system is VERY leaky. Fluids
are forced out of the thin walls of the
capillaries by pressure. This fluid is picked up
by the lymphatic tissues and returned to veins.
158Components of blood
- The __________ contains water, metabolite (like
glucose and vitamins), wastes, ions (sodium,
chloride, etc) and proteins.
159Components of blood
- The plasma contains water, metabolite (like
glucose and vitamins), wastes, ions (sodium,
chloride, etc) and proteins.
160Components of blood
- The cellular portion of the blood is made up of
three different types of cells.
161__________ blood cells (erythrocytes)- shaped
like a float disk, carry oxygen, replaced
frequently.
162Red blood cells (erythrocytes)- shaped like a
float disk, carry oxygen, replaced frequently.
163Anemia is caused by a decrease in the number of
red blood cells.
164________ blood cells (leukocytes)- used in the
immune system for defense.
165WHITE blood cells (leukocytes)- used in the
immune system for defense.
166Leukemia is caused by an overproduction of white
blood cells.
167__________ - play a key role in blood clotting.
Red blood cell
White blood cell
168Platelets (blue)- play a key role in blood
clotting.
Red blood cell
White blood cell
169The heart is divided into ___________
chambers-left atrium, right atrium, left
ventricle, right ventricle.
170The heart is divided into four chambers-left
atrium, right atrium, left ventricle, right
ventricle.
171A small cluster of cells in the right
atrium,called the sinoatrial node (SA node),
initiate contraction of the heart.
172The SA node acts as the ___________ of the heart,
spontaneously starting contractions with a
regular rhythm.
173The SA node acts as the pacemaker of the heart,
spontaneously starting contractions with a
regular rhythm.
174After initiation, the wave of contraction spreads
across both atria, is delayed for an instant, and
then spreads to the ventricles by the
atrioventricular node (AV node) and Bundle of
His.
175? Pump your Blood song ? From Happy DaysSang by
the character Potsie Webberhttp//www.sitcomsonli
ne.com/happydays.html
176?Pump, pump, pumps your blood?The right atriums
where the process begins, where the CO2 blood
enters the heart. ? Through the tricuspid valve,
to the right ventricle, the pulmonary artery, and
lungs. ? Once inside the lungs, it dumps its
carbon dioxide and picks up its oxygen supply. ?
Then its back to the heart through the pulmonary
vein, through the atrium and left ventricle. ?
Pump, pump, pumps your blood
177?Pump, pump, pumps your blood ? The aortic
valves, where the Blood leaves the heart, then
it's channeled to the rest of the bod ? The
arteries, arterioles, and capillaries too bring
the oxygenated blood to the cells ? The tissues
and the cells trade off waste and CO2, which is
carried through the venules and the veins ?
Through the larger vena cava to the atrium and
lungs, and we're back to where we started in the
heart ? Pump, pump, pumps your Blood
178Blood flows through the heart in the following
order
vena cava-right atrium-tricuspid valve-right
ventricle-pulmonary valve-pulmonary
artery-lungs-pulmonary veins-left atrium-bicuspid
valve-left ventricle-aortic valve-aorta-body
179- Blood pressure is a measure of cardiovascular
function. - During the fist part of the heartbeat, the atria
are relaxed and filling with blood. - This is called the __________ pressure.
180- Blood pressure is a measure of cardiovascular
function. - During the fist part of the heartbeat, the atria
are relaxed and filling with blood. - This is called the diastolic pressure.
181- The second part of the heartbeat is when the
ventricles contract, pushing blood out into the
body. - This is called the __________ pressure.
182- The second part of the heartbeat is when the
ventricles contract, pushing blood out into the
body. - This is called the systolic pressure.
183Another way to monitor the heart is through
measuring the tiny electrical impulses produced
by the heart when it contracts.A recording of
this is called an __________.
184Another way to monitor the heart is through
measuring the tiny electrical impulses produced
by the heart when it contracts.A recording of
this is called anelectrocardiogram.
185Hypertension is high blood pressure and can lead
to heart damage, stroke, or kidney failure.
186Atherosclerosis is a buildup of fatty deposits on
the inner walls of arteries.
187Respiratory System
188Respiratory System
Provides your body with a constant supply of
oxygen
189__________
- filters particles,
- moistens and
- warms the air
190Nose
- filters particles,
- moistens and
- warms the air
191__________
Upper throat (common tract for both food and air)
192Pharynx
Upper throat (common tract for both food and air)
193__________
Long tube that carries air to the lungs. (A flap
called the epiglottis cover the trachea when you
swallow so that food and liquids do not go into
your lungs)
194Trachea
Long tube that carries air to the lungs. (A flap
called the epiglottis cover the trachea when you
swallow so that food and liquids do not go into
your lungs)
195__________
Two branches-one goes to the left lung, one goes
to the right lung
196Bronchi
Two branches-one goes to the left lung, one goes
to the right lung
197__________
Millions of tiny sacs where exchange of oxygen
and carbon dioxide occurs
198Alveoli
Millions of tiny sacs where exchange of oxygen
and carbon dioxide occurs
199Breathing is the result of pressure changes that
occur inside the thoracic cavity.
200During inhalation, the __________ contracts and
moves downward and the rib cage moves upward and
outward.
201During inhalation, the diaphragm contracts and
moves downward and the rib cage moves upward and
outward.
The air pressure inside the lungs decreases,
causing air to rush in.
202During exhalation, the diaphragm and ribs return
to their original position and this compression
forces air out of the lungs.
203As blood flows through the lungs, oxygen is
picked up by red blood cells, which contain
hemoglobin.
204Every breath is initiated by the respiratory
control center in the brain, which sends signals
to the diaphragm to contract.
205Asthma is a disease in which the bronchioles
constrict, making it hard to breathe.
206Emphysema is caused by cigarette smoking, which
damages the alveoli.
207Lung cancer is caused by abnormal cell growth
often due to cigarette smoking.
208Digestive System
209Digestion is the process of breaking down food
into smaller molecules that can be absorbed by
the body.
210Mouth?Saliva moisten and lubricates the food
?Saliva contains the enzyme __________ , which
begins breakdown of carbohydrates
211Mouth?Saliva moisten and lubricates the food
?Saliva contains the enzyme amylase , which
begins breakdown of carbohydrates
212Esophagus?Tube that connects the mouth to the
stomach?__________ contractions push the food
down ?A sphincter separates esophagus stomach,
preventing acid reflux
213Esophagus?Tube that connects the mouth to the
stomach?Peristaltic contractions push the food
down ?A sphincter separates esophagus stomach,
preventing acid reflux
214Stomach?The stomach secretes hydrochloric acid,
which breaks down proteins ?The mixture of food
and gastric juice is churned and becomes
__________
215Stomach?The stomach secretes hydrochloric acid,
which breaks down proteins ?The mixture of food
and gastric juice is churned and becomes chyme
216Small Intestine?The small intestine is wound
up-unwound it would be 20 feet long!?The SI is
lined with fingerlike projections called
__________ that increase the surface area and
allow for faster absorption of food and water.
217Small Intestine?The small intestine is wound
up-unwound it would be 20 feet long!?The SI is
lined with fingerlike projections called
microvilli that increase the surface area and
allow for faster absorption of food and water.
218Small Intestine?Most digestive enzymes are made
in the pancreas and secreted into the SI ?The
liver makes bile which is secreted into the SI
and helps fat digestion. ?The complete digestion
of carbohydrates, fats and proteins occurs in the
SI
219Small Intestine?Nutrients that are absorbed
from the small intestine are sent to the liver,
which modifies the nutrients, and detoxifies
alcohol
220Large Intestine?No digestion just some
absorption of ___________ and vitamins ?Wastes
are compacted and sent to the rectum and then out
throughthe anus
221Large Intestine?No digestion just some
absorption of water and vitamins ?Wastes are
compacted and sent to the rectum and then out
throughthe anus
222Excretory System
223Humans eliminate wastes in a process called
excretion. Excretion rids the body of nitrogen
wastes like ammonia, excessive water, salts, etc.
224Kidneys ? Two small bean-shaped organs located
in the lower back
225Kidneys ? Three main sections of the kidney
cortex (outer layer), medulla (inner layer),
renal pelvis
226Kidneys ? The kidneys form urine and regulate
the amount of water and salt in the blood. ?
Kidney failure is life threatening.
227Kidneys ? Urine produced by the kidneys passes
through the ureters and into the urinary bladder.
? Urine leaves the bladder and exits the
__________
228Kidneys ? Urine produced by the kidneys passes
through the ureters and into the urinary bladder.
? Urine leaves the bladder and exits the
Urethra
229The Nervous System
230Nerve cells can quickly transmit messages to the
body. A nerve cell, or _____________, consists
of three basic parts the cell body, the
dendrites, and the axon. Dendrites receive
information and send it to the cell body. Then
the information travels along a single axon to
other cells.
231Nerve cells can quickly transmit messages to the
body. A nerve cell, or neuron consists of three
basic parts the cell body, the dendrites, and
the axon. Dendrites receive information and send
it to the cell body. Then the information
travels along a single axon to other cells.
232Impulses, known as action potentials, are passed
from one nerve to the next.
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234Many nerves are covered by a myelin sheath, which
speeds the nerve impulse by allowing
________________ conduction. In multiple
sclerosis, the myelin sheath is destroyed,
interfering with nerve transmission.
235Many nerves are covered by a myelin sheath, which
speeds the nerve impulse by allowing saltatory
conduction. In multiple sclerosis, the myelin
sheath is destroyed, interfering with nerve
transmission.
236The _________ Nervous System-The Brain spinal
cord
237The central Nervous System-The Brain spinal
cord
238Brain Stem (Medulla) heart rate, respiration,
blood pressure, coughing, sneezing and digestion.
239Cerebellum responsible for coordinated
movement, balance, posture and muscle tone
240Hypothalamus body temperature, appetite, water
balance, thirst and blood pressure
Thalamus relays information between spinal cord
and cerebellum.
241Cerebrum (Cerebral Cortex) intellect, memory,
language, personality and motor function.
242The brain can be divided into four major lobes
occipital, temporal, parietal, and frontal.
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244The __________ Nervous System
245The Peripheral Nervous System sensory nerves and
motor nerves
246Sensory nerves gather information about your
environment and body conditions and deliver it to
the central nervous system.
247Motor Nerves transmit information from the
central nervous system to muscles and glands
248Somatic voluntary muscles (skeletal muscles)
249Autonomic involuntary muscles (cardiac smooth
muscles)
250dominant during times of stress fight or
flight increases blood pressure, heart rate,
breathing rate decreases digestion
__________ -
251dominant during times of stress fight or
flight increases blood pressure, heart rate,
breathing rate decreases digestion
Sympathetic -
252__________ more relaxed state conserves energy
decreases heartbeat and breathing increases
digestion
253Parasympathetic more relaxed state conserves
energy decreases heartbeat and breathing
increases digestion
254Special Senses
255Ear hearing and equilibrium
- Sound waves enter the ear canal and hit the
eardrum, causing it to vibrate. - Behind the eardrum are three small bones called
ossicles which transmit the vibration to the
cochlea. - The cochlea is a fluid-filled chamber with hair
cells, which bend and send nerve signals to the
brain.
256Eyes
257Eyes
Sclera tough outer layer (white of the
eye) Cornea bends and focuses light rays Pupil
where light enters the eye
258Eyes
Iris controls the amount of light entering the
eye (colored part of eye) Lens focuses light on
the rear of the eye Retina light sensing
portion generates nerve impulses rods and cones
259Taste Taste buds are connected to nerves that
send information to the brain.
There are four basic taste sensations salty,
sour, sweet, bitter
260Smell olfactory receptors line the nose
261Skin senses touch, temperature, pain, etc.
262The End