Post on 13-Dec-2015
35.1 Organization of the Body
• Nervous System– Structures:
• Brain• Spinal cord• Peripheral nerves
– Function:• Recognizes &
responds to Δs in external & internal env.
35.1 Organization of the Body
• Integumentary System– Structures:
• Skin• Hair• Nails• Sweat & oil glands
– Function :• Barrier against infection• Protect against radiation• Regulate temp.
35.1 Organization of the Body
• Respiratory System– Structures:
• Nose• Pharynx• Larynx• Trachea• Bronchi• Bronchiols• Lungs
– Function:• Oxygen for respiration• Remove CO2
35.1 Organization of the Body
• Digestive System– Structures:
• Mouth• Pharynx• Esophagus• Stomach• Small & large intestines• rectum
– Function:• Break down food• Absorb nutrients• Eliminate waste
35.1 Organization of the Body
• Excretory System– Structures:
• Skin• Lungs• Kidneys• Ureters• Urinary bladder• Urethra
– Function:• Eliminate waste
35.1 Organization of the Body
• Skeletal System– Structures:
• Bones• Cartilage• Ligaments• Tendons
– Function:• Support body• Protect organs• Allow movement• Store minerals• Site of blood cell formation
35.1 Organization of the Body
• Muscular System– Structures:
• Skeletal muscle• Smooth muscle• Cardiac muscle
– Function:• Voluntary movement• Circulate blood• Move food through digestive system
35.1 Organization of the Body
• Circulatory System– Structures:
• Heart• Blood vessels• Blood
– Function:• Bring oxygen, nutrients, & information to
cells• Remove wastes• Regulate body temp.
35.1 Organization of the Body
• Endocrine System– Structures:
• Hypothalamus• Pituitary• Thyroid• Parathyroids• Adrenals• Pancreas• Ovaries/testes
– Function:• Control growth• Development• Metabolism• Maintain homeostasis
35.1 Organization of the Body
• Reproductive System– Structures:
• Testes• Epididymis• Vas deferens• Urethra• Penis• Ovaries• Fallopian tubes• Uterus• Vagina
– Function:• Reproductive cells• Nurtures/protects embryo
35.1 Organization of the Body
• Lymphatic/Immune System– Structures:
• White blood cells• Thymus• Spleen• Lymph nodes• Lymph vessels
– Function:• Protect from disease• Return fluid to circulatory system
Organization of the Body
• Multicellular organisms– Organ system: group of organs that
perform closely related functions–Organs: group of tissues that work
together to perform a complex function
–Tissues: group of similar cells that perform a single function
–Cells: basic unit of life
Goal of all body systems
• HOMEOSTASIS!– Balance w/in the body– Maintain a stable environment– Feedback inhibition
• Negative feedback• Shuts off original signal• Thermostat/hypothalamus example
Homeostasis & feedback inhibition
Room temp. increases Room temp. decreases
Senses temp change & turns on
heating system
Senses temp change & turns off
heating system
35.3 Central Nervous System
• Brain & spinal cord– Protected by skull & vertebrae– Meninges wrapped around 3x
• Note: meningitis
– Cerebrospinal fluid• Protects (shock absorber)• Nutrients & waste exchange
Parts of the Brain
• Cerebrum– Voluntary & conscious thought– Intelligence, learning, judgment
• Cerebellum– Coordinates movement– Balance
• Brain Stem– Connects brain to spinal cord
• Thalamus & Hypothalamus– Thalamus: gets sensory info & directs it– Hypothalamus: hunger, thirst, fatigue, anger,
temp
Reflexes
• Automatic response to stimuli• Allow body to respond w/o thought
– Esp important in danger situations
• Ex: blinking & sneezing
35.2 Nerves
• Communication network– Send & receive signals throughout body– Monitors & controls internal conditions – Respond to stimuli
• 3 types– Sensory
• organ spinal cord
– Motor• Brain muscles
– Interneurons• Sensory motor
Nerves
nucleuscell body
dendrites
axon
myelin sheath
nodes
axon terminals
• At rest– Na+ ions pumped out,
K+ ions pumped in but leak out
– Outside cell has a + charge
– Inside cell has a – charge
• Moving impulse– Stimuli– Reverses charge (+
inside, - outside)