Title: How Humans Work
1How Humans Work
2Table of Systems
- Nervous
- Integumentary
- Respiratory
- Circulatory
- Digestive
- Skeletal
- Excretory
- Reproductive
- Endocrine
- Muscular
- Immune
3Nervous System
- What is it made of? brain, spinal cord, and
peripheral nerves. - What does it do? Controls the body in response to
internal and external environments. - Standards?
- b. Students know how the nervous system mediates
communication between different parts of the body
and the body's interactions with the environment.
- c. Students know how feedback loops in the
nervous and endocrine systems regulate conditions
in the body. - d. Students know the functions of the nervous
system and the role of neurons in transmitting
electrochemical impulses. - e. Students know the roles of sensory neurons,
interneurons, and motor neurons in sensation,
thought, and response.
42 Main Sections
- The nervous system is divided into 2 sections
the central nervous system (brain and spinal
cord) and peripheral nervous system. (everything
outside the central nervous sys). - The CNS central nervous system is the
control center for the body. This part of the
nervous system sends, analyzes, and processes
messages to and from the rest of the body. The
spinal cord is the way that the brain controls
and sends information to the rest of the body. -
- central
nervous system-gt - The PNS peripheral nervous system
- is the part of the nervous system where it comes
- into contact with the environment. It is whatever
- Is not in the CNS.
52 Parts of the Peripheral System.
- Somatic nervous system controls VOLUNTARY
actions. Motor neurons send information from the
brain and spinal cord to control actions like
moving legs and hands. These are all actions that
occur under conscious control. - -sometimes- there are rapid responses that
happen so quick, people dont think about it
before movement takes place. This is a reflex
when neurons in the spinal cord automatically
make certain motor neurons take action. Reflexes
keep a person from harm. Example if you touch
something hot, you automatically back off so you
do not get burned! - On the other hand
- The autonomic nervous system controls AUTOMATIC
activities like the beating of the heart and
the persons breathing. This system help keeps
the body alive without making the person to
always have to think about it
6How the Nervous System Works
- Neurons are essential in this system. They send
impulses messages in the form of electric
signals to the rest of the body. - Sensory neurons (afferent) send messages from
sense organs TO the central nervous system. This
is how humans sense their surroundings. - There are pain receptors, thermoreceptors -
temperature, mechanoreceptors sounds, touch,
and motion, chemoreceptors chemicals, tastes,
and photoreceptors - light. - Motor neurons (efferent) bring messages FROM the
brain and spinal cord to muscles and glands. This
is how peoples muscles and glands take action. - Interneurons connect the two types of neurons
and send impulses between the two.
7What are Neurons Made of?
- Neurons have a cell body which has the nucleus
and most of the cytoplasm. - NEURONS HAVE DENDRITES AND AXIONS.
- Dendrites carry impulses to the cell body of the
neuron. - Axons carry impulses away from the cell body.
- Some neurons have a membrane called the myelin
sheath around the axon. The membrane has gaps in
it, which are called nodes. Because of this, when
an impulse is sent, the impulse jumps from node
to node on the axon membrane RATHER THAN moving
along the membrane this makes it faster. - CLICK HERE.
8Synapses?
- The nervous system communicates with the whole
body with the help of neurons. Neurons send
information to other neurons without even
touching each other! HOW? - SYNAPSES. A synapse is a gap that separates each
neuron from another neuron. An axon terminal is
the end of a neuron the synapse is in between
the axon terminal of one neuron and the dendrites
of a different neuron or cell. Since the two
cells do not touch, a neuron must send
neurotransmitters across the synapse (chemicals
that send the impulse). - The impulse is then changed from an electrical
impulse to a chemical impulse. - Synapses are essential so that impulses do not
travel backwards.- they only go in one direction. - The nervous system adjusts to the feedback loops
it receives. Based on if it is good or bad
feedback, the nervous system turns certain
actions on and certain actions off to maintain
homeostasis. - Ex if something is bitter, the body will not
want to eat that thing again, based on the bad
feedback. - To keep the body alive and to survive, the brain
forces people to do certain actions. This helps
promote and keep homeostasis. - Ex In the medulla oblongata in the brain,
impulses are sent that FORCE you to
breathebecause breathing is so important!
9Integumentary System
- What is it made of? skin and nails, hair and
glands, andnerve receptors. - What does it do? Protects the body, regulates
temperature, protects pigments from UV rays, and
produces vitamin D.
10What does this SKIN do?
- the nerve receptors help let the body identify
thefeel of things, temperature, pain, and
pressure.without these receptors, people would
not realizewhen they are in harm and can hurt
their bodyvery badly.keeps important materials
in and harmful thingsout! It is a barrier
between the outside world andthe inside of the
body. - regulates body temp it can produce vitamin
D. it can help control the bodys
temperature.insulates body with a layer of
fatloose connectivetissue underneath the
surface. Sweat can control body temperatures,
but also help get rid of unwantedchemicals in
the body.
11What does skin do
- its waterproof and it can heal
itself!!protects pigments from UV rays- Melanin
keeps skinfrom burning - The epidermis has melanocytes. (cells that make
melanin.) Melanin is pigment in the skin.
Peoples skin color are different, even though
everybody has the same amount of melanocytes. In
darker people, the melanocytes just produce MORE
melanin. - Melanin absorbs UV radiation to protect the body,
but too much is not good! - to protect the body from harmful things, the
skincreates oils. It makes the skin
soft--However, toomuch can result in acne!
12Layers
- Skin is made of 2 main layers. Epidermis
dermis. - Epidermisouter layer, thin, mostly dead cells
- The epidermis reproduces/divides rapidly because
skin cells fall off constantly - Older cells are pushed to the surface when newer
ones are formed. - The older cells are forced to be flat, and they
lose their cell contents and make KERATIN-strong
protein that has many fibers and is part of the
basic structure of hair and nails. - Keratincytes-cells that make keratin- they die,
and when they do, they become a waterproof
covering for the skin. This is how skin is
waterproof and protects the body. Keratin also
makes the skin flexible and tough so it doesnt
break easily. - DERMIS thick layer of skin. Living cells. under
the Epidermis. - The dermis has blood vessels, nerve endings,
glands, sense organs, smooth muscles, and hair
follicles.
13Dermis
- Helps monitor body temperatures.
- When it is cold, the dermis blood vessels
narrow. This way, it helps the body keep its
heat, and there is less heat loss. - When it is hot, the vessels grow larger. This
makes the body warm and heat is released so the
body will lose heat. - The layer of loose connective tissues is in the
hypodermis, which is under the dermis. This layer
helps conserve the bodys heat. - The dermis has 2 main types of glands.
- Sweat and sebaceous (oil) glands
- They release their contents through tiny holes in
the epidermis. - Sweat glands produce release sweat (99 water,
1 salts and fats) to cool the body because the
evaporation takes heat away. - Sebaceous glands make sebum (an oily secretion
made of fats, waxes, hydrocarbons). Sebum keeps
the epidermis flexible waterproof. Sebaceous
glands also secrete oils to keep the condition of
the hair moist.
14Hair
- HAIR made of dead cells that are filled with
keratin - Made by cells called hair follicles (epidermal
cells that reach into the dermis) - Protects the head from the suns harmful light
- Hair in the nose, ears, and around eyes keeps
particles from entering. It traps them. - Eyebrows eyelashes keep sweat from getting into
eyes. - Hair helps insulate the body from coldness.
15Nails
- Nails grow from the nail root. The nail root is
an area of cells growing very fast. When the
cells divide, the nail root cells fill up on
keratin and make strong nails that help protect
fingers toes. - They also help mammals get a good grasp on items
and help them to be able to scratch.
16Respiratory System
- What is it made of? Nose, pharynx, larynx,
trachea, bronchi, branchioles, lungs - What does it do? Brings in oxygen for the body
and gets rid of carbon dioxide waste. - Standards?
- a. Students know how the complementary activity
of major body systems provides cells with oxygen
and nutrients and removes toxic waste products
such as carbon dioxide.
17Starting at the mouth
- Air goes in through the pharynx a tube in the
back of the mouth. - It then moves to the trachea the wind pipe.
- On top of the trachea is the larynx which
contains the vocal cords. From the layrnx, the
air journeys through the trachea to 2 bronchi.
These are large passageways in the chest cavity,
each leading to a lung. In the lung, the bronchi
extend to become smaller bronchi called
bronchioles then the bronchioles divide into
alveoli tiny air sacs in clusters, surrounded
by capillaries. - THIS IS WHERE GAS EXCHANGE OCCURS!!
18Gas Exchange
- In the Alveoli
- OXYGEN dissolves because of the moisture in the
inner part of the alveoli. The oxygen then
diffuses across the capillary walls into the
bloodstream. - Carbon dioxide, on the other hand, diffuses in
the opposite direction, from the blood to the
alveoli. So then the air is exhaled.getting rid
of the CO2!
19Inhaling
- When you breathe, air pressure, not muscle, is
what moves the air into the lungs. However,
muscle is needed to inflate lungs. - Lungs are in 2 sacs in the chest cavity.
- There is a muscle under the chest cavity that
expands the chest cavity volume when the person
is inhaling. This produces a partial vacuum in
the chest cavity! This only will happen if the
cavity is sealed, because a puncture to the chest
can cause air to leak, and breathing would not
work!
20Exhaling
- As the diaphragm relaxes, the person exhales.
This is because the pressure in the cavity is
GREATER than the outside atmospheric pressure.
Air must come back out from the lungs. - However, even though exhaling is usually passive,
if you voluntarily exhale, more muscle and force
is required. Therefore, there are muscles around
the chest cavity that contract as the diaphragm
relaxes. These muscles help make enough force to
blow air out. -
- Video---CLICK HERE.
- Animation
21Circulatory System
- What is it made of? Heart, blood vessels, blood
- Function? To circulate blood through everywhere
in the body. To get rid of wastes (Co2) and
supply oxygen to all organs and tissues. - Standards?
- a. Students know how the complementary activity
of major body systems provides cells with oxygen
and nutrients and removes toxic waste products
such as carbon dioxide.
22Heart.
- Structure of the heart muscle
- Septum/wall separates the LEFT section from the
RIGHT - Upper chamber receives blood from the body
(atrium) - Lower chamber pumps blood out to the body
(ventricle) - There are 4 chambers. Two of each kind. (A right
and left for each)
23Types of circulation
- There is two types of circulation.
- Pulmonary circulation on the right side of the
heart. Pumps oxygen deprived blood from the
HEART to LUNGS. - At the lungs, carbon dioxide leaves the blood and
oxygen is now in the blood. The oxygen-full blood
then goes into the hearts left side, and is
pumped to the rest of the body. - Systemic circulation left side of the heart.
Pumps oxygen-RICH blood that came from the lungs
to the HEART and to the WHOLE BODY. - When the cells take oxygen from the blood, the
blood now is poor in oxygen. The blood then goes
back to the right side of the heart and is pumped
to the lungs. - Valves in the heart (flaps of connective tissue)
are very useful in this system. They keep the
oxygen-rich and oxygen-poor blood from mixing.
Furthermore, they prevent blood flowing out the
heart from flowing back in. Valves in veins also
keep blood from flowing the wrong way. - Animation
24 25How does the heart beat?
- Both the atria and the ventricles have a network
of muscle fibers. Whenever one fiber is
stimulated, the whole network is. - A group of cardiac muscle cells (sinoatrial node
in the right atrium) gives the signal to
contract. The Atrium contracts. - Then the signal is picked up by a network of
fibers in the atria called atrioventricular node.
The signal is then transferred to a network of
fibers in the ventricles..which causes the
ventricles to contract. - Heres the pattern
- Network in atria contracts-gt blood goes out
ventricles - From ventricles-gt blood moves out of the heart
and through the body. - Animation
26Blood vessels
- Blood vessels are how the blood gets around the
body. - 3 types ARTERIES, VEINS, CAPILLARIES.
- Arteries are big vessels. They carry oxygen rich
blood TO the body (except for pulmonary
arteries). Thick walls withstand pressure that
the heart creates when it pushes blood into these
arteries. Elasticity helps it withstand pressure.
27Capillaries
- Capillaries smallest blood vessels. Only 1 cell
wideso blood cells must line up in single file
before going through the capillaries. These
vessels are important because they are the site
where oxygen and carbon dioxide are exchanged
from the alveoli to blood cells, and vice versa.
28Veins
- Veins bring back oxygen to the heart. Many veins
are located near skeletal muscles, because the
movement of blood in veins is against gravity.
Muscles contracting help move the blood. Also,
that is why in large veins, there are valves to
prevent blood from flowing back down.
Example of a vein and a valve that controls the
blood flow-gt
29Digestive System
- Function to break down food into pieces so that
the bodys cells can use it more easier to make
it into energy. - Composed of mouth, pharynx, esophagus, stomach,
small and large intestines, salivary glands,
pancreas, liver. - Standards
- f.Students know the individual functions and
sites of secretion of digestive enzymes
(amylases, proteases, nucleases, lipases),
stomach acid, and bile salts. - g.Students know the homeostatic role of the
kidneys in the removal of nitrogenous wastes and
the role of the liver in blood detoxification and
glucose balance.
30Traveling through the digestive system.
- First, we start at the mouth. The mouth
mechanically breaks food into smaller pieces with
strong teeth. - In the mouth, salivary glands release saliva,
which makes food easier to eat. It also begins
digesting food. Saliva has an enzyme amylase-
which breaks down starches and breaks chemical
bonds between sugar and starches.
31The Esophagus
- The food next goes down the esophagus.. Into the
stomach. The esophagus is a tube that transports
food its smooth muscles push the food down. - A cardiac sphincter prevents food from coming
back up the esophagus, but overeating can make it
open.
32In the stomach
- The contractions from its smooth muscles help mix
the food. - The stomach lining has gastriac glands that
release secretions.. - Mucus protects stomach wall
- Hydrochloric acid makes stomach contents acidic
- Pepsin enzyme that digests protein
- Stomach acids fluids mixed together. CHYME
-
- After the stomach, the chyme goes into the
duodenum, the 1st part of the small intestine.
Here, most of the chemical digestionoccurs. - The chyme is mixed with enzymes and secretions
from the pancreas, liver, and drodenum lining. - The chyme is still being digested .. . . . .
33Extra Info..
- Pancreas below the stomach. It is a gland that
makes hormones to control blood sugar levels. - It makes enzymes that break down carbohydrates,
proteins, lipids, and nucleic acids. (proteases,
nucleases, lipases) - Kidneys homeostatic role removes waste as urine
- Liver above the stomach.
- Makes bile fluid with lipids and salts in it to
dissolve fats, store glucose, and break down
toxic substances. The bile fluid is stored in an
organ called the gall gladder.
34Intestines
- Small Intestines
- The chyme, now, is mostly digested!
- The small intestine absorbs the nutrients from
the chyme. The surface of the intestine is
covered in villi and microvilli. Each villus is a
network of blood capillaries and vessels that
absorb and transport nutrients. The small
intestine uses its smooth muscles to contract and
move the chyme.
35Last stop large intestines!
- Large Intestines
- it is the large intestines job to remove water
from what is left of the cells. After water is
moved across the large intestine wall, what is
left is waste. The waste materials pass the
rectum and into the toilet.
36Skeletal System
- FUNCTIONS!
- It supports the body to stand up and supports
soft tissues. Its the framework of the body.
Gives muscles something to attach to, so it helps
movement. Bones are the things that move when
muscles contract. Bones can act as levers. - -to protect internal organs from damage.
- -bones store and release chemicals and helps
maintain the amount of chemicals. - Made of BONES AND CARTILAGE, TENDONS, AND
LIGAMENTS
37Bones.
- Bones are active tissues. They are made of
special cells (found only in bones) and protein
fibers. Calcium salts surround those cells. - Periosteum is a connective tissue that covers the
bone. In this cover, there are blood vessels that
transport oxygen and nutrients to bone. - Compact bone is right under of the periosteum.
But it is not SOLID. It is made of tubes of
Mineral Crystals and Protein Fibers. - Spongy bone is inside the outer layer of the
compact bone. - Spongy bone is arranged at points of stress so
that they can support a lot of force. They are
NOT really spongy. But-they are strong and not
as heavy as the dense compact bone. - Why are bones not solid? Theyd be way too heavy!
Then - It would be too hard to move.
38Bone Marrow
- In bones, there is bone marrow. Bone marrow is
soft tissue found in bone cavities and there are
2 types. These two are important in the body. - -red bone marrow produces red blood cells. white
blood cells, and platelets made in the spongy
bone. - -bones are where blood cells are made! Blood
cells made in soft marrow tissue inside the
bones. - -when bones grow old the red bone marrow turns
yellow, and the yellow marrow is important
because it stores chemical energy. Stores fat.
Yellow marrow can also change into red marrow if
there is a lot of blood loss in the body. Now it
can make blood cells. - -bones have storages of minerals, mainly calcium
salts, that are significant to processes of the
body.
39Special Bone Cells
- OSTEOCLASTS-from the bone marrow formed from 2
cells joining together. DISSOLVE BONE when bone
is broken, damaged, etc so new healthy bone can
be formed. - OSTEOBLASTS- from bone marrow create NEW bone.
These cells work with each other in teams to make
new bone. These cells release mineral deposits
that forms bone tissue. This bone tissue replaces
cartilage. The osteoblasts turn into osteocytes
when they are surrounded by bone tissue this is
how they know their job is successful and
complete. - OSTEOCYTES- inside the bone these cells are in
charge of the growth and changing the shape of
bones. They maintain the actions of the other
cells. Osteocytes know when there is damage or
cracks in the bone. Then, these cells tell the
osteoclasts where to dissolve the bone. - those cells take part in ossification- when
cartilage is replaced by bone. This happens in
all humans, when they are babies.
40Whats cartilage? Tendons? Ligaments?
- Cartilage made of collagen fibers and elastin.
Cartilage absorbs shock, helps places of the body
become flexible (EX NOSE EARS), Cartilage is
found on the ends of jointed bones, creates an
elastic surface for joints so they can move
smoothly. - CARTILAGE IS ALSO IN BABIES. When theyre
just born. When they grow, bone replaces the
cartilage. HOWEVER------cartilage has no blood
vessels, so it needs diffusion to transport
Nutrients from (CAPILLARIES) into it. - Tendons attach muscle to bone. Tendons also send
energy and force from them muscles to the bone. - Ligaments connect bone to bone so they stay
together.
41Joints
- JOINTS are places where one bone attaches to
another. Joints help MOVEMENT happen without
hurting the bone. Joints keep bones apart so they
dont hit, and they also hold bones in place. - Three types of joints
- Slightly moveable-lets movement happen, but has
limits. Bones are separated. - Immovable joints-bones are fused together or
connected by connective tissue. - EX SKULL! The bones must be joined together to
provide full protecting for the - brain
- Freely movable-these joints let movement go in 1
directions. Ex ball socket, - pivot, saddle, hinge.
42Excretory System
- Function maintains homeostasis. Gets rid of
wastes (salts, CO2, urea) - Made of skin, lungs, kidney, bladder, urethra.
- Standards
- a. Students know how the complementary activity
of major body systems provides cells with oxygen
and nutrients and removes toxic waste products
such as carbon dioxide. - g.Students know the homeostatic role of the
kidneys in the removal of nitrogenous wastes and
the role of the liver in blood detoxification and
glucose balance.
43Kidney
- Kidneys are the main organs of this system. It
filters blood with wastes in it the kidney takes
out the wastes, excess water, and urea as it
passes through the kidneys artery. Then the
clean blood returns to the bloodstream to
circulate the body. - A nephron is a unit in a kidney that does work.
Each is independent and has its own blood supply.
Blood enters through an arteriole. When it goes
through the capillaries, the blood is filtered.
Waste products are collected in a collecting
duct. The waste is then led to the ureter. The
cleaned blood leaves the nephron through the
venule.
44Blood filtration in the kidneys
- Filtration Occurs in glomerulus (network of
capillaries by a structure called Bowmans
capsule). Pressure in the blood makes water,
salt, glucose, amino acids, and urea to go to the
Bowmans capsule however, since proteins,
plasma, and platelets are too large to pass the
permeable membrane, they stay in the blood. The
materials that are filtered into the capsule are
called FILTRATES - Reabsorption Most of the filtrate goes back into
the blood by reabsorption. Not all of it is
excreted. Nutrients and water are removed from
the filtrate and are reabsorbed by capillaries,
back into the blood. What is left behind is
urine. - Secretion as water and nutrients are reabsorbed
into the bloodstream, secreted materials are
being put into the filtrate from the capillaries.
Hydrogen ions are transferred from the blood into
the filtrate.
45After reabsorption
- After reabsorption, urine, which is made of
excess salts and water, is emptied into the
collecting duct (then later out the body). - Result filtered blood reenters the bloodstream.
Urine is released through urethra.
46Kidneys are important in homeostasis
- Kidneys are important in controlling homeostasis.
- Kidneys can monitor things in the blood.
- Activity is controlled mostly by what is in the
blood. The kidney can realize if there is an
increase in water in the blood. It can make water
reabsorption decrease. The kidney then makes less
water go back into the blood (because there is
already and increase) more excess water is
disposed of.
47Reproductive
- Function to make children
- To make sex cells gametes
- In females function to nurture the baby and
protect it when it is developing. - Organs testes, epididymis, vas deferens,
urethra, penis - male - Ovaries, Fallopian tubes, uterus, vagina - female
48Creation of Children
- This system is essential to create children.
- It is NOT essential for a human to survive, but
it IS essential for the species to live on. - This system creates gametes -gt sex cells. Gametes
are special from other cells of the body because
it has half the of chromosomes. - When an ovum and a sperm combine, it fertilizes
and eventually becomes a new human being!! - This system can only create active reproductive
cells gametes - once the person reaches
pubertyand that is when their reproductive
organs are fully developed and functioning.
49Puberty
- FOR BOTH THE MALE FEMALE!
- Puberty starts when pituary glands are signaled
to create higher amounts of hormones. The
hormones FSH and LH change the persons
appearance, and also change their reproductive
organs to be more mature and developed. - Follicle-stimulating hormone (FSH) and
luteinizing hormone (LH)
50Male
- LH makes cells in the seminiferous tubules to
release testosterone. FSH helps sperm mature - When hormones from puberty are released, the
males body creates testosterone -gt male sex
hormone. Testosterone makes males grow more body
hair, grow in size, and have a deeper voice. - TESTES male gonads. Gonads are sex organs.
- The new hormones, including testosterone, also
make the body create sperm. Sperm is the male
reproductive gamete (sex cell) and are created in
seminiferous tubules, which are small tubules in
the testes. The testes are in a scrotum. The
scrotum is a sac, part of the reproductive
organs, which contains the testes. The scrotum
moves up towards the body for heat when it is
cold, or when it is hot, the sac moves down. The
scrotum is in charge of keeping a proper
temperature for the sperm to be created. Sperm is
produced in the process of meiosis.
51Journey of the Sperm
- The sperm then travels to the epididymis, where
the sperm is stored and matures. Then, the sperm
moves through the vas deferens (tube) that later
joins together with another tube called the
urethra. As the sperm travels to the end of the
penis, seminal vesicles, the prostate gland, and
the bulbourethral gland release seminal fluid.
The seminal fluid combines with the sperm
creating semen. Through the urethra, the semen
then is ejaculated out of the body through the
penis. - Semen is released by the automatic nervous system
of the mans body when he is sexually excited. It
happens automatically, usually not voluntarily,
when a male and female are in the act of
reproducing.
52Female
- Female the released FSH makes cells in the
ovaries of the woman to make estrogen.female sex
hormone. The female develops physical
characteristics wider hips, growth in breasts. - Only one egg ovum (female gamete) is made each
month. - Female gonad OVARY
- There are two ovaries, and in each ovary, there
are around 400,000 primary follicles (premature
eggs) unlike men, women do not make new eggs.
They are born with what they have. A follicle is
a developing egg surrounded by follicle cells.
Follicle cells help an egg mature. Eggs mature in
their follicles.
53Female pt 2
- Caused by the hormone FSH, about every month, a
follicle grows bigger and the egg goes through
meiosis. - Then, a large egg (containing ½ the number of
regular chromosomes HAPLOID) and 3 smaller
cells polar bodies- will be created however,
the polar bodies are not important and will
become cell waste. - Now, the follicle has matured and breaks open,
letting the egg travel from the ovaries one of
the 2 Fallopian tubes. This is ovulation. Tiny
hairs in the tube help move the egg into the
uterus. - The uterus thick and muscular lining is prepared
to receive and nurture a fertilized egg until it
grows into a baby but if fertilization did not
occur, the egg and the lining are disposed of
through the vagina. - This menstrual cycle (when an egg develops, is
released, goes to the uterus, and goes out of the
vagina), is also called a period.
54Endocrine System
- Made of the following glands pituitary gland,
parathyroid gland, pineal gland, the
hypothalamus, thyroid, adrenal, pancreas and the
ovaries/testes. - Function controls growth, metabolism, and
reproduction. This system watches over the
processes and growth of the human over time. - Standards?
- a. Students know how the complementary activity
of major body systems provides cells with oxygen
and nutrients and removes toxic waste products
such as carbon dioxide. - c. Students know how feedback loops in the
nervous and endocrine systems regulate conditions
in the body. - i.Students know how hormones (including
digestive, reproductive, osmoregulatory) provide
internal feedback mechanisms for homeostasis at
the cellular level and in whole organisms.
55Glands
- 2 types of glands.
- EXOCRINE release products through tubes, ex
sweat and tears. - ENDOCRINE release products into bloodstream.
(endocrine glands secrete hormones).
56Hormones
- Hormones affect our whole body. They are
chemicals that transmit information to only
certain cells that are meant to receive the
message. Hormones cause changes in peoples
bodies when they are growing in age. They travel
to a specific placecalled target cells. The
shape of the hormone must match the shape of the
target cell so they can fit together. - Once the receptor protein/target cell is
activated by the protein, its activities change
(because its shape changed!) Its like an on/off
switch activated by the hormone.
Picture of hormones going to their target cells-gt
57Hormones
- 2 types of hormones steroid these hormones can
cross cell membranes of target cells easily. They
attach to a DNA control sequence and can directly
turn on or turn off certain genes of the cell. - Nonsteroid hormones usually cannot pass through
cell membranes, so it is harder for them to reach
their target cells. The hormone attaches to
receptors on the cell membrane, activating an
enzyme that then activates more messengers that
carry the message to the inside of the cell.
58Glands functions
- Some functions for the glands of the system
- Hypothalamus makes hormones that control
pituitary gland. - Pituitary gland makes hormones that regulate
other endocrine glands. - Parathyroid glands secrete a parathyroid hormone
controls amount of calcium in blood. - Thymus releases thymosin during a persons
childhood to activate the creation of more T
cells. - Adrenal glands release hormones that help the
body handle stress. - Thyroid makes thyroxine monitors metabolism
- Pancreas makes insulin and glucagon monitors
amount of glucose in blood. - Reproductive gonads (sex organs)
- -Female ovaries make progesterone and
estrogen. - Estrogen gives the woman more female
characteristics - (wider hips and development of breasts) and also
help the eggs - develop. Progesterone helps make the uterus
ready for a fertilized - egg.
- - Male Testis make testosterone, which make
the male gain - more size, hair, and have a deeper voice.
59Homeostasis
- The Endocrine System is important in keeping
homeostasis stable because it affects the affects
cells, tissues and organs activities
everywhere in the body. Hormones give feedback to
the endocrine system to keep the body at a
well-monitored state. - There is negative and positive feedback.
- Most hormone systems use negative feedback to
control the amount of hormone released. In
negative feedback, substances are released to
stop the release of a certain hormone. - In positive feedback, substances are release to
activate the release of a certain hormone. - This is how the body knows when to release
hormones and when to stop. Thus, the body also
maintains homeostasis. - EX puberty. The endocrine system gets a signal
for when to start releasing hormones. Another
example release of sweat when the body is hot.
maintaining homeostasis.
60Muscular System
- Purpose to let the body be able to move, to help
move food through the digestive system, and to
regulate blood pressure. - Made of 3 types of muscles skeletal, smooth,
cardiac - Standards
- h.Students know the cellular and molecular basis
of muscle contraction, including the roles of
actin, myosin, Ca2, and ATP.
61What the different types of muscles do.
- Smooth muscles
- are usually not voluntarily controlled. Smooth
muscles are in the stomach, blood vessels, and
intestines and they move food through the
digestive system. They are connected to one
another by gap junctions this lets electric
impulses be transferred from one muscle to
another one.
62Cardiac muscles
- Cardiac muscles are only in the heart. They are
not under complete voluntary control of the
central nervous system. We do not have to think
about using these muscles. Cardiac muscles are
connected to each other also by gap junctions
63Skeletal Muscles
- Skeletal muscles are made from alternating
thicknesses of filaments. - Thick contains myosin (a protein).
- Thin made of mainly actin
- THESE TWO PROTEINS MAKE MUSCLES CONTRACT! The
muscles contract when thin filaments slide over
thick ones.
64How muscles contract
- In muscle contraction, myosin filaments attach to
a binding site on an actin. This is called a
cross bridge. - With the help of ATP, the myosin crossbridge
changes shape. It then pulls the actin toward the
center, and the crossbridge is broken. - Then myosin bonds to another actin, and the cycle
starts again. - Skeletal muscle contractions are controlled by
impulses from motor neurons. The impulses tell
the muscles what to do. - Muscle contraction needs ATP energy!
- Calcium ions control regulatory proteins those
regulatory proteins allow actin and myosin to
interact with one another.
65Immune System
- Made of white blood cells, t cells, b cells.
- Function to protect the body from and to get rid
of harmful bacteria and viruses. - Standards
- a. Students know the role of the skin in
providing nonspecific defenses against infection.
b. Students know the role of antibodies in the
body's response to infection.c. Students know
how vaccination protects an individual from
infectious diseases.d. Students know there are
important differences between bacteria and
viruses with respect to their requirements for
growth and replication, the body's primary
defenses against bacterial and viral infections,
and effective treatments of these infections. - e. Students know why an individual with a
compromised immune system (for example, a person
with AIDS) may be unable to fight off and survive
infections by microorganisms that are usually
benign. - f.Students know the roles of phagocytes,
B-lymphocytes, and T-lymphocytes in the immune
system.
66Defense.
- Non specific defenses block everything out
- First line of defense keeps pathogens out
- Skin prevents things from entering the body
- Mucus, sweat, saliva, and tears can keep them
from entering - Hairs can keep dust from entering the body
- Skin-gt
672nd line of defense
- 2nd line of defense inflammatory response a
reaction to pathogens entering the body and a
response to tissue damage. In this response,
phagocytes (cells that engulf other cells to
destroy them) track and try to kill the
pathogens. - White blood cells fight invaders.
- The immune system can also make the temperature
of the body rise to kill pathogens and slow them
down from spreading .. This is a fever.
68Specific Defenses
- When a pathogen makes it across the nonspecific
defenses, it now faces specific ones. (this is
called an immune response). - ANTIGENS trigger the response.
- lymphocytes (type of white blood cell) make
ANTIBODIES to fight the pathogens. Antibodies
track certain antigens down. - The antibodies attach to the pathogen with a
certain, specific antigen. There are antigen
bonding sites on the antibody, where they attach.
- Antibodies help destroy antigens by clumping the
antigens into a big group. This big clump will
draw in phagocytes and the phagocytes will
eat and get rid of the whole clump of
antibodies and antigens.
69How are SPECIFIC antibodies made?
There are millions of B cells (AKA B lymphocytes
type of white blood cell) in our body. When
they develop, each cells genes slightly change.
Therefore, each cell can make a different
antibody .. But the differences are small. When
a pathogen gets into the body, the antigens on
the pathogen are detected by SOME of the B cells
only some, because all of them are slightly not
the same. When this certain group of B cells
senses a specific antigen, it produces very
quickly and releases plasma cells. Plasma cells
are specialized B cells. Plasma cells release
antibodies to clump the pathogens and get rid of
them. T cells (T lymphocytes another white
blood cell) help activate plasma cells.
70Why do people stay immune to a pathogen if they
have already had it?
- People stay immune to previously experienced
pathogens because their T cells and B cells
remember how to fight against it. Because of
this, the T cells and B cells can quickly get rid
of the pathogens when it is detected.
71Vaccines
- Active Immunity is when the body receives a
WEAKER form of a pathogen and becomes immune to
it. B cells can detect certain antigens, and when
it does, it creates many plasma cells that
release antibodies to destroy the pathogen. When
a weaker form of a pathogen is entered into the
body (a vaccine) the B cells can make antibodies
against it to protect the body without having the
body being harmed!
72HIV/AIDS
- When a persons immune system is compromised, the
body can no longer fight the disease as well.
Therefore, the person may die from a disease that
their white blood cells cannot fight off.
73Whats the Difference?
- Whats the difference between bacteria and
viruses? - BACTERIA living things. They can be killed by
antibiotics and medicines. - VIRUSES are not living. To get rid of them, rest
and help your immune system do the job for you.
74Sources
- Sources used
- http//www.sirinet.net
- http//www.besthealth.com/
- http//www.drstandley.com/
- http//www.ivy-rose.co.uk/
- http//depts.washington.edu/
- http//www.emc.maricopa.edu/
- http//www.kidshealth.org
- http//faculty.washington.edu
- http//www.estrellamountain.edu/
- http//www.thinkmuscle.com
- Prentice Hall Biology Book
- Mr. Thiel (on the previous slide)