bio bio bio
BIOL 106 Exam 4 Study Guide
Covers material from Chapters 29, 30, 31, 32
Chapter 29 – Respiratory System
Functions: to take in oxygen and release carbon dioxide
• Includes
o Nasal passages
o Pharynx (throat)
o Larynx (voice box, where vocal chords are located)
o Trachea (windpipe)
o Bronchi (two; bring air to inflate lungs)
o Bronchioles (branch from bronchi down to alveoli)
o Lungs
§ Major respiratory organ
§ Site of gas exchange between air and blood
• Alveoli (tiny membranous sacs that exchange gases)
o Site of interaction between cardiovascular and respiratory systems
Breathing – ventilating the lungs (required for gas exchange)
• Diaphragm – a sheet of muscle located just below the terminal end of the lungs
o When muscle contracts and relaxes, the volume of the lungs change
§ Inhalation – diaphragm increases the volume of the lungs
• Diaphragm contracts, pulling downward in chest/abdominal cavity
• Pressure in lungs decreases, draws air into lungs
• Opening plunger of syringe
§ Exhalation - diaphragm decreases the volume of the lungs
• Diaphragm relaxes, moving upward in chest/abdominal cavity
• Pressure in lungs increases, expelling air from the lungs (deflating)
• Depressing plunger of syringe
• Increased respiration/breathing rate
o Increased heart rate to deliver more oxygen through cardiovascular system
o Increase in cellular respiration in tissues (need for more oxygen)
o Decrease the pH of blood (by removing carbon dioxide)
Gas Exchange
• Linkage between respiratory and cardiovascular system
o Red blood cells (carry oxygen to tissues)
§ Hemoglobin protein is specialized to carry oxygen molecules on the surface of RBCs
• Composed of 4 heme groups with iron atom
o 1 oxygen molecule binds to the iron of a heme group
• Each hemoglobin protein can carry 4 oxygen molecules
§ RBCs can have up to 250 hemoglobin proteins per cell
• That’s a lot of oxygen that can be carried
• Erythropoietin (EPO)
o Hormone that stimulates RBC production
§ Released by the kidneys
§ RBCs produced in bone marrow
§ More RBCs may be needed when body cannot meet oxygen consumption demands
• Elevation
Chapter 30 – Central Nervous System
Function: sense and respond to stimuli in the environment, allows us to perceive and understand the world around
us, translates thought into actions
• Broken into 2 components:
o Central Nervous System (CNS)
§ Brain and spinal cord
§ Transmits signals between brain and body
• Nerves – long fibers of neurons and specialized tissue
o Transmit signals through the nervous system
§ Sensory input is received and integrated here
o Peripheral Nervous System (PNS)
§ All the nervous tissue outside the central nervous system
§ Nerves to distant body sites (fingers and toes)
§ Sensory input is received here and relayed to CNS for processing
Neurons – specialized cells that act as the building blocks of the nervous system
• Generate electrical signals
• Parts of a neuron
o Cell body – contains nucleus and most organelles
o Dendrites – extensions to sense incoming signals
o Axons – elongated section to conduct nerve signals away, to the next neuron or ector cellserent types: components of PNS
§ Myelin sheath insulates axon to conserve electrical message as it travels down axon (action
potential)
o Axon terminal – axon tips that transmit signaling chemicals to neighboring cells
§ Neurotransmitters released into the synaptic cleft from axon terminals to relay signal to
neighboring cells
• Two di
o Sensory – receive information from the external world and transmit it to the CNS
o Motor – transmit information from the CNS to muscle cells (ector cells) resulting in musclespring
contraction/relaxation
Regions of the Brain
• Cerebellum
o Processes sensory information
o Controls movement coordination and balance
• Brain stem
o Located at the base of the brain
o Coordinates involuntary functions like reflexes, heart rate, and breathing
• Diencephalon
o Located right above the brain stem
o Regulates homeostatic functions like body temperature, hunger, thirst, and sex drive
o Includes hypothalamus and anterior pituitary (endocrine system)
• Cerebrum
o Largest part of the brain
o Outer layer called cerebral cortex
o Intelligence, learning, perception, and emotional processing
Chapter 31 – Reproductive System
Function: to produce reproductive gamete cells (egg and sperm) needed for sexual reproduction of o
• Female Reproductive Anatomy
o Ovaries
§ Produce eggs
§ Produce hormones estrogen and progesterone
§ Ovulation – release of egg from ovaries
o Oviduct (Fallopian Tubes)
§ Tube that connects ovaries and uterus
§ Traditionally the site of fertilization (fusion of egg and sperm)
o Uterus
§ Elastic muscular compartment that supports developing fetus
§ Lined with tissue called endometrium
• Site where embryo attaches to uterus and begins development
o Vagina
§ Opening of female reproduction where intercourse takes place
§ Extends to cervix, opening of uterus
• Male Reproductive Anatomy
o Testes (testicles)
§ Paired glands that produce the hormone testosterone
§ Contained in a sac of skin called scrotum
o Seminiferous tubules
§ Tightly coiled tubes located in testes
§ Site of sperm development
o Epididymis
§ Sperm mature here
o Vas deferens
§ Sperm travel through this series of tubes before ejaculation
o Urethra
§ Where semen and urine is released
o Prostate
§ Gland that adds fluid to sperm
§ Creates semen, sperm and fluid that can be released for fertilization
o Penis
§ Organ that delivers sperm to female vagina
Fertilization – fusion of 1 sperm cell with the egg
• Typically occurs in the oviducts (Fallopian tubes)
• Can occur if intercourse happens before ovulation, sperm can survive until fusion
Menstruation – shedding of the endometrial lining
• Driven by hormones released during di`erent times of a 28 day cycle
o FSH & LH produced in brain
o Estrogen & progesterone produced in ovaries
Chapter 32 – Immune System
Function: defend the body against pathogens
Pathogens - foreign particles that cause a response in the immune system
• Viruses – influenza (know Spanish Influenza = most deaths), COVID, HIV, chicken pox
• Bacteria – food poisoning, STIs, strep throat
• Parasites (fungi/protists) – athlete’s foot, malaria, giardia
Virus – infectious particle
• Considered nonliving – does not contain cells; but does have
o Nucleic acid (DNA or RNA)
o Protein cell (capsid)
o Envelope of lipids (not all viruses have this)
• Route of infection
o Attachment
o Penetration
o Synthesis
o Assembly
o Release
Immune System (composed of 2 parts)
• Innate immunity
o Non-specific defenses (first line of defense)
o Present from birth and are always active
§ Physical barriers
• Layers of tightly packed cells to prevent pathogens from entering the body
o Skin (outside of body)
§ Prevents invaders from entering
o Mucous membranes (lining of inside of body)
§ Sticky substance traps invaders
§ Chemical barriers
• Stomach acid, tears, saliva, complement proteins in blood
o Can destroy invading pathogens
§ Specialized white blood cells called phagocytes
• Adaptive immunity
o Mediated by specialized white blood cells called lymphocytes
§ Lymphocytes recognize antigens (specific molecules found on the surface of pathogens
that triggers an adaptive immune response)
§ Derent kinds of lymphocytes found in the body and only recognize particular antigensective secondary response
• B cells - bone marrow
• T cells - thymus
o Composed of 2 components:
§ Humoral immunity – targets free-floating pathogens in bodily fluid
• Helper T cells & B cells recognize bacterial and viral pathogens
• Antibodies – produced by B cells
o Circulate in bodily fluids and help to fight infections
§ Can bind to antigens and block from doing harm
§ Signal phagocytes to ingest pathogens
§ Trigger complement proteins to destroy pathogen
§ Cell-mediated immunity – targets infected or altered body cells
• Cytotoxic T cells
o Become activated by foreign antigen on phagocyte cell surface
o Targets foreign cells
o Long-lasting immunity against specific pathogens
o Has memory component
§ Primary Immune response
• First time exposed to a specific pathogen
• T & B cells are activated
• Levels of antibodies increase
• Memory B cells are produced
• Takes 7-10 days to develop (sick first go round)
§ Secondary immune response
• Occurs on second exposure to specific pathogen
• Memory B cells hop into action
o Stronger and longer immune response
o Prevents getting sick second go roud
Vaccines – provoke primary response to a pathogen without exposure
• Body is able to establish memory B cells in primary response
• Prepares body for e
• Let to a great reduction in pandemics since 1900s