Systems Packet
For each chapter please do the following before we discuss the chapter in class.
1) Title and label each set of images. Study any slides that you are given.
2) If you cannot explain the image, read about it and write notes next to the images.
3) Make certain you understand the main ideas for each chapter---the big picture. Read the below outlines to guide you and define all terms where indicated.
Chapter 40---Animal Form and Function
1) Understand that physical laws and the environment constrain animal size and shape. Define the following terms: anatomy, physiology, convergent evolution, and surface-to-volume ratio.
2) Understand that animal form and function are correlated at all levels of organization. Know the where you would find the following tissue and their function-epithelial, connective, nervous, and muscle.
3) Understand that animals use the chemical energy in food to sustain forma and function. Define the following terms: metabolic rate, endothermic, ectothermic, and basal metabolic rate.
4) Understand that many animals regulate their internal environment within relatively narrow limits. Understand the following terms: homeostasis, the three components of homeostatic control systems-a receptor, a control center, and an effector- negative and positive feedback.
5) Understand that thermoregulation contributes to homeostasis and involves anatomy, physiology, and behavior. Define the following terms: thermoregulation, conduction, convection, radiation, and evaporation. Know that thermoregulation takes place through adjustment of the rate of heat exchange, evaporation, behavioral responses, and alteration of the rate of metabolic heat production (in endotherms).

Chapter 41---Animal Nutrition
1) Understand that homeostatic mechanisms manage an animal’s energy budget. There are four main feeding mechanisms of animals; suspension feeders, substrate feeders, fluid feeders, and bulk feeders. Know the terms herbivore, carnivore, and omnivore. Know how animals store excess calories as glycogen in the liver and muscles and as fat in fat tissues. The energy stores are tapped when ATP is low. Blood glucose level is maintained within a relatively narrow range by negative feedback.
2) Understand that an animals diet must supply carbon skeletons and essential nutrients.
3) The main stages of food processing are ingestion, digestion, absorption, and elimination. Define intracellular digestion and extracellular digestion. Define a gastrovascular cavity and a complete digestive tract or alimentary canal.
4) Each organ of the mammalian digestion system has specialized food-processing functions. Know the entire route food travels as it is ingested, digested, and excreted. Know what each organ does along the path. Know how and where carbohydrates, proteins, nucleic acids, and fats are broken down.
5) Evolutionary adaptations of vertebrate digestive systems are often associated with diet. A mammal’s dentition is generally correlated with its diet.

Chapter 42---Circulation and Gas Exchange
1) Know that circulatory systems reflect phylogeny. Know what a gastrovascular cavity does and what open and closed circulatory systems are. Know that hemolymph is the blood and lymph fluid that bathes the organs directly in open circulatory systems. Know that a heart has an atria and ventricles and that the main types of blood vessels in humans are the arteries, veins, and capillaries.
2) Know the steps of double circulation in mammals. Know that the complete cycle of contraction and relaxation of the heart is called the cardiac cycle with the contraction phase being called the systole and the relaxation phase is called the diastole. Heart rate is the rate of contractions per minute, and stroke volume is the amount of blood pumped by the left ventricle during each contraction. Know that the sinoatrial (SA) node is the pacemaker of the heart and the AV node delays the impulses from the SA node to allow the atria to completely empty before the ventricles contract.
3) Know that blood pressure-the hydrostatic pressure that blood exerts against the wall of a vessel-and the lymphatic system- that returns lost fluid and proteins to the blood in the form of lymph-govern blood circulation.
4) Know that blood is connective tissue with cells suspended in plasma. Know what plasma is and what red blood cells (erythrocytes), white blood cells (leukocytes) and platelets are. Know that blood contains fibrinogen which forms clots when it is converted to its active form, fibrin.
5) Know that gas exchange occurs across specialized respiratory surfaces. Define countercurrent exchange in gills. Know that insects have tracheal systems that are air tubes that branch through the body and open to the outside. Know that the larynx is the voice box, the tracheas is the windpipe that divides into two bronchi that branch into bronchioles and end in clusters of airsacs called alveoli, the sites of gas exchange.
6) Know that breathing ventilates the lungs, i.e. the inhalation and exhalation of air and in mammals this involves movement of the diaphragm. The diffusion of gas depends on partial pressure (high to low).
7) Know that respiratory pigments bind and transport gases. Hemoglobin is the respiratory pigment found in almost all vertebrates. A lowering of the pH in blood lowers the affinity of hemoglobin for oxygen, and oxygen dissociates—this the Bohr shift. CO2 is carried in the blood in the form of bicarbonate ions.

Chapter 43---The Immune System
1) Know that innate immunity provides broad defenses against infection. Skin and mucous membranes cover the surface and line the opening of the animal body providing a barrier against infectious agents. Microbes that get through the skin encounter specific white blood cells called neutrophils that ingest and destroy them in a process called phagocytosis. Monocytes (a phagocytotic leukocyte) migrate into tissues and develop into macrophages, which are giant phagocytotic cells. Eosinophils are leukocytes that defend against parasitic invaders such as worms by positioning themselves near the parasite’s wall and discharging hydrolytic enzymes. Damage to tissue by physical injury or entry of pathogens leads to release of numerous chemical signals that trigger the inflammatory response. For example, histamines trigger the dilations and permability of nearby capillaries aiding in the delivery of clotting agents to the injured area.
2) Know that in acquired immunity, lymphocytes provide specific defense against infection. Vertebrates have two types of lymphocytes: B lymphocytes (B cells) , which proliferate in the bone marrow, and T lymphocytes (T cells), where lymphocytes mature in the thymus. They circulate through the blood and lymph, and both recognize particular microbes and are said to show specificity. Antigens are foreign molecules that elicit a response by lymphocytes. Antibodies are proteins secreted by B cells during an immune response. Antigen receptors are located on the antigen and allow B and T cells to recognize them. Antigen receptors on T cells are called T cell receptors, and they recognize antibodies specifically. When an antigen binds to a B or T cell, the lymphocyte becomes activated and forms two clones of cells. One is made up of effector cells, which combat the antigen, and the other consists of memory cells, which are long-lived and bear receptors for the same antigen. This process is called clonal selection. When the body is first exposed to an antigen and a lymphocyte is activated, this is referred to as the primary immune response. Upon second exposure to the antigen, the secondary immune response is faster and of greater magnitude. Lymphocytes and all other blood cells arise from stem cells in the bone marrow.
3) Know that the humoral and cell-mediated immunity defend against different types of threats. Active immunity develops naturally in response to an infection; it also develops artificially by immunization (vaccination). In immunization, a nonpathogenic form of a microbe or part of a microbe elicits an immune response to an immunological memory for that microbe.
4) Know that the immune system’s ability to distinguish self from nonself limits tissue transplantation. Antigens on the surface of red blood cells determine whether a person has type A, B, AB, or O blood. Because antibodies to nonself blood antigens already exist in the body, transfusion with incompatible blood leads to destruction of the transfused cells and a life-threatening situation for the patient. MHC molecules are responsible for stimulating the rejection of tissue grafts and organ transplants. The chances of successful transplantation are increased if the donor’s tissue bearing MHC molecules closely matches the recipient’s. The recipient also must take immunosuppressant drugs.
5) Know that exaggerated, self-directed, or diminished immune responses can cause disease. In localized allergies such as hay fever, IgE antibodies produced after first exposure to an allergen attach to receptors on mast cells. The next time the same allergen enters the body, it bonds to mast cell-associated IgE molecules, inducing the cell to release histamine and other mediators that cause vascular changes and typical symptoms.

Chapter 44---Osmoregulation and Excretion
1) Know that osmoregulation balances the uptake and loss of water and solutes. Define osmoregulation.
2) Know that an animal’s nitrogenous wastes reflect its phylongeny and habitat. Most metabolic wastes must be excreted from the body. One of the most important types of waste products is nitrogen-containing products of the breakdown of proteins and nucleic acids. Enzymes remove nitrogen from these compounds to create ammonia. Some animals excrete ammonia directly into water, where it becomes diluted. Others convert it first to urea in the liver, where ammonia is combined with carbon dioxide in an endergonic reaction, or to uric acid. Uric acid is more energetically expensive to produce, but it is insoluble in water and can be excreted as a paste or crystals.
3) Know that diverse excretory systems are variations on a tubular theme. Most excretory systems produce urine in a two-step process. First, the body fluid (blood or hemolymph) is collected; then the composition of the fluid is adjusted by selective reabsorption of solutes. Insects and terrestrial arthropods such as the grasshopper have Malpighian tubules that remove nitrogenous wastes. They open into the digestive tract and dead-end at points in the hemolymph. The tubules secrete nitrogenous wastes and salts into the lumen, and water follows by osmosis.
4) Know that nephrons and associated blood vessels are the functional units of the mammalian kidney. Mammals have two kidnesy, and each is supplied with a renal artery and renal vein. Urine leaves the kidneys through the ureters, which drain into the urinary bladder. Urine is expelled from the body through the urethra. The kidney has two regions, the outer renal cortex and the inner renal medulla. Each region is packed with nephrons. Nephrons are made up of a single long tubule and the glomerulus, a ball of capillaries. At one end of the tubule is the Bowman’s capsule, a C-shaped structure that surrounds the glomerulus. The filtrate flows through the proximal tubule, the descending loop of Henle, the loop of Henle, the ascending loop of Henle, and the distal tubule. The distal tubule empties into a collecting duct, which receives wastes from many nephrons. The filtrate empties into the renal pelvis. The five main steps in the transformation of blood filtrate to urine are: 1. In the proximal tubule, secretion and reabsorption changes the volume and compositions of the filtrate. The pH of body fluids is controlled, and bicarbonate is absorbed, as are NaCl and water. 2. In the descending loop of Henle, reabsorption of water continues. 3. In the ascending loop of Henle, the filtrate loses salt without giving up water and becomes more dilute. 4. In the distal tubule, K+ and NaCl levels are regulated, as is filtrate pH. 5. The collecting duct carries the filtrate through the medulla to the renal pelvis, and the filtrate becomes more concentrated by the movement of salt.
5) Know that the mammalian kidney’s ability to conserve water is a key terrestrial adaptation. Antidiuretic hormone helps regulate water balance. It is produced in the hypothalamus and stored in and released from the pituitary gland. Angiotensin and aldosterone are also involved in water regulation-define how.

Chapter 45---Hormones and the Endocrine System
1) The endocrine system and the nervous system act individually and together in regulating an animal’s physiology. Hormones are chemical signals released into body fluids that communicate messages around the body. Target cells are those cells equipped to respond to hormones. The endocrine system of an animal is the sum of all its hormone-secreting cells and tissues. Hormone-secreting organs are called endocrine glands. Many endocrine glands contain neurosecretory cells, which secrete hormones. Many chemicals act as both hormones and nervous system signals (neurotransmitters). Feedback is one important way by which the endocrine and nervous system are regulated.
2) Know that hormones and other chemical signals bind to target cell receptors, initiating pathways that culminate in specific cell responses. Chemical signals may bind to receptors on the plasma membranes of certain cells, triggering a signal transduction pathway. A signal transduction pathway consists of a series of molecular events that initiates a response to the signal. Alternately, the signal enters the target cell and binds to a receptor in the cell. The receptor then acts as a transcription factor, causing a change in gene expression,. Hormones in the body can affect one tissue, a few tissues, or most of the tissues in the body as with sex hormones, or they may affect other endocrine glands (these last are referred to as tropic hormones). Define tropic hormones.
3) Know that the hypothalamus and pituitary integrate many functions of the vertebrate endocrine system. The hypothalamus receives information from nerves throughout the body and from other parts of the brain then initiates endocrine signals in response. The posterior pituitary is an extension of the hypothalamus that stores and secretes two hormones (oxytocin and ADH) that are made by certain neurosecretory cells located in the hypothalamus. The anterior pituitary consists of endocrine cells that synthesize and secrete at least six hormones into the blood. Tropic hormones released from the hypothalamus regulate the anterior pituitary.
4) Know that nonpituitary hormones help regulate metabolism, homeostasis, development, and behavior. Learn the calcium and insulin feedback loops. Know the glands, hormones they secrete, and the representative action of each hormone.

Chapter 46---Animal Reproduction
1) Define sexual and asexual reproduction. Define budding, fragmentation, parthenogenesis, and hermaphroditism.
2) Know that fertilization depends on mechanisms that help sperm meet eggs of the same species. Define external and internal fertilization. Gonads are the organs that produce gametes in most animals.
3) Know that reproductive organs produce and transport gametes: focus on humans. The males external reproductive organs are the scrotum and penis, and the internal organs are gonads (which produce gametes and hormones), accessory glands (which secrete necessary fluids), and ducts (which carry sperm and glandular secretions). The testes are made up of many highly coiled tubules, called seminiferous tubules, the site of sperm production. In between the tubules are Leydig cells, which produce testosterone and other androgens. The testes are held in the scrotum. The sperm passes from the seminiferous tubules into the epididymis. During ejaculation, the sperm is propelled through the vas deferens, which ultimately meets up with a duct from the seminal vesicle and forms an ejaculatory duct which opens into the urethra. The seminal vesicles, the prostate gland, and the bulbourethral gland all contribute secretions that make up semen. These secretions supply necessary nutrients and medium for the sperm cells. The female gonads are the two ovaries. Each ovary contains many microscopic follicles. Follicles consist of one egg surrounded by one or more layers of follicle cells, which help to develop, nourish, and protect the egg cell. One follicle matures and releases its egg cell during each menstrual cycle. The follicle cells also produce estrogens, the female hormones. The egg cell is released from the follicle during ovulation. The remaining follicle tissue heals and row in the ovary to form a body called a corpus luteum, which secretes estrogen and progesterone. Progesterone helps to maintain the uterine wall during pregnancy. If the egg cell is not fertilized, the corpus luteum disintegrates. The egg cell is released into the oviduct, and cilia lining the oviduct convey the egg cell down to the uterus. The inner lining of the uterus is called the endometrium. At the base of the uterus is the cervix, which leads to the vagina, the canal through which a baby is born.
4) Know that in humans and other mammals, a complex interplay of hormones regulates gametogenesis. Spermatogenesis is the production of mature sperm cells, and it occurs in the seminiferous tubules. The cells that give rise to sperm are called spermatogonia. They undergo meiosis and differentiation eventually to form mature, motile sperm. Oogenesis is the development of mature ova. Oogonia are the cells that develop into ova: they multiply and begin meiosis, but they stop at prophase I of meiosis I. These egg cells are called primary oocytes, which are quiescent until puberty. From puberty onward, FSH periodically stimulates a follicle to grow and its egg cell to complete meiosis I and begin meiosis II. This forms the secondary oocyte. Humans and other primates have menstrul cycles. Menstruation occurs when the endometrium is shed from the uterus through the cervix and vagina. Other mammals have estrous cycles. The menstrual flow phase of the female cycle is the phase during which menstrual bleeding occurs. The proliferative phase of the menstrual cycle is that during which the endometrium begins to regenerate and thicken. In the secretory phase, the endometrium continues to thicken, and if an embryo has not implanted in the lining by the end of this phase, menstrual flow occurs. The ovarian cycle parallels the menstrual flow cycle and begins with the follicular phase, in which several follicles begin to grow. At the end of the follicular phase, ovulation occurs, during which the secondary oocyte is release from the ovary. During the luteal phase of the ovarian cycle, endocrine walls in the corpus luteum secrete hormones.
5) Know that in humans and other placental mammals, an embryo grow into a newborn in the mother’s uterus, and pregnancy, or gestation, is the condition of carrying one or more embryos in the uterus. Human gestation culminates in birth, or parturition, which is brought about by a series of strong rhythmic uterine contractions.

Chapter 47---Animal Development
1) After fertilization, embryonic development proceeds through cleavage, gastrulation, and organogenesis. Cleavage, which is a period of rapid mitotic cell division, partitions the cytoplasm of the zygote into smaller cells called blastomeres, each of which has its own nucleus. Continued cleavage leads to a ball of cells called a morula, and then a fluid-filled central cavity called the blastocoel forms within the morula to produce a blastula. Gastrulation is a drastic rearrangement of the cells in the blastula. In gastrulation, three (germ) cell layers are produced-the ectoderm, endoderm, and mesoderm. Organogenesis is the development of the three germ layers into the rudiments of organs.

Chapter 48---Nervous System
1) Know that the nervous system consist of circuits of neurons and supporting cells. Sensory receptors collect information about the world outside the body as well as processes inside the body. The central nervous system (CNS) consists of the brain and spinal cord, and the peripheral nervous system (PNS) consists of the nerves that communicate motor and sensory signals throughout the rest of the body. Motor output is the conduction of signals from the CNS to effector cells which are muscle or gland cells that carry out responses. The neuron is the functional unit of the nervous system. It is composed of a cell body which contains the nucleus and organelles; dendrites, which are cell extensions that receive incoming messages from other cells; and axons, which convey messages to other cells. Many axons are covered by and insulating fatty myelin sheath. Synaptic terminals, at the end of axons, relay signals from one neuron to another neuron or other cell through chemical messengers called neurotransmitters. A simple nerve circuit is the reflex arc, in which a sensory nerve receives information and passes it on to the spinal cord and then to a motor neuron, which signals an effector cell. Ganglia are cluster of nerve cells. Glia are supporting nerve cells, and they outnumber nerve cells in the body. Three important kinds of glia are astrocytes, which provide support for neurons; oligodendrocytes, which form myelin sheaths in the SND; and Schwann cells, which form myelin sheaths in the PNS.
2) Know that ion pumps and ion channels maintain the resting potential of a neuron. Membrane potential describes the difference in electrical charge across a cell membrane. The membrane potential of a nerve cell at rest is called the resting potential. It exists because of differences in the ionic composition of the extracellular and intracellular fluids across the plasma membrane. Changes in the membrane potential of a neuron are what give rise to a nerve impulse.
3) Action potentials are the signals conducted by axons. An action potential (nerve impulse) in and all-or-none depolarization of the membrane of the nerve cell. It opens voltage-gated sodium channels, and Na+ ions enter the cell, bringing the membrane potential to a positive value. The membrane potential is restored to its normal resting value by the inactivation of Na+ channels and by opening voltage gated K+ channels, which increase K+ leaving the cell. A refractory period follows the action potential, corresponding to the interval when the Na+ channels are inactivated. Action potentials are propagated along the axon; salutatory conduction, which is the jumping of the nerve impulse between nodes of Ranvier (areas on the axon not covered by the myelin sheath), speed up the conduction of the nerve impulse.
4) Neurons communicate with other cells at synapses. The signal is conducted from the axon of a presynaptic cell to the dendrite of a postsynaptic cell via an electrical or chemical synapse. Electrical synapses occur via gap junctions. In chemical synapses, neurotransmitters are released by the presynaptic membrane into the synaptic cleft. They bind to receptors on the postsynaptic membrane and are then broken down by enzymes or taken back up into surrounding cells. Excitatory postsynaptic potential (EPSP) is the electrical charge caused by the binding of the neurotransmitter to its receptor on the postsynaptic membrane. Inhibitory postsynaptic potential (IPSP) is the voltage charge associated with chemical signaling at the inhibitory synapse. Acetylcholine is a very common neurotransmitter, it can be inhibitory or excitatory.
5) The vertebrate nervous system is regionally specialized. The peripheral nervous system (PNS) consists of paired cranial and spinal nerves and associated ganglia. The PNS is divided into the somatic nervous system, which carries signals to skeletal muscles, and the autonomic nervous system, which regulates the primarily automatic, visceral functions of smooth and cardiac muscles, including those in the gastrointestinal, cardiovascular, excretory, and endocrine systems. The autonomic nervous system is composed of the sympathetic division-which, when activated, causes the heart to beat faster and adrenaline to be secreted—and the parasympathetic division, which has the opposite effect when activated. The vertebrate brain develops from three embryonic regions; the forebrain, the midbrain, and the hindbrain. In humans, the most expansive growth occurs in the part of the forebrain that gives rise to the cerebellum. The brainstem is made up of the medulla oblongata, pons, and the midbrain. The brainstem controls homeostatic functions such as breathing rate, conducts sensory and motor signals between the spinal cord and higher brain center, and regulates arousal and sleep. The cerebellum helps coordinate motor, perceptual, and cognitive functions. The thalamus is the main center through which sensory and motor information passes to and from the cerebrum. The hypothalamus regulates homeostasis; basic survival behaviors such as feeding, fighting, fleeing and reproducing; and circadian rhythms. The cerebrum has two hemispheres, each of which consists of a cerebral cortex overlying white matter and basal nuclei, which are important in planning and learning movements. In mammals, the cerebral cortex has a convoluted surface called the neocortex. A thick band of axons, the corpus callosum, provides communication between the right and left cortices.
6) The cerebral cortex controls voluntary movement and cognitive functions. Each side of the cerebral cortex has four lobes, frontal, temporal, occipital, and parietal—which contain primary sensory areas and association areas. Portions of the frontal and temporal lobes, including Broca’s area and Wernicke’s area, are essential for generation and understanding language.

Chapter 49---Sensory and Motor Mechanisms
1) Sensory receptors transduce stimulus energy and transmit signals to the central nervous system. Define mechanoreceptors, thermoreceptors, chemoreceptors, electromagnetic receptors, and pain receptors.
2) The mechanoreceptors involved with hearing and equilibrium detect settling particles or moving fluid. There are three regions in the mammalian ear. The outer ear is the external pinna and auditory canal. These collect sounds and direct them to the tympanic membrane (eardrum), which separates the outer ear from the middle ear. In the middle ear, vibrations are conducted through three small bones (the malleus, incus, and stapes) and through the oval window. Then the vibrations are conducted to the inner ear, which consists of a labyrinth of channels lined by membrane and containing fluid, all situated in bone. The inner ear contains the cochlea, a two-chambered organ, which is involved in hearing. The organ of Corti, which is in the cochlea, contains the receptors of the ear, which are hair cells with “hairs’ that project into the cochlear duct. The cochlea transduces the energy of the vibrating fluid into action potentials, in a wave that dissipates at the round window. Some organs in the inner ear are responsible for detecting body position and balance. These are the semicircular canals.
3) The senses of taste and smell are closely related in most animals. Taste buds are modified epithelial cells situated on different parts of the tongue and mouth.
4) Similar mechanisms underlie vision throughout the animal kingdom. Compound eyes (insects and crustaceans) consist of up to several thoughsand light detectors called ommatidia, each of which has its own lens. Single-lens eyes are found in vertebrates and some invertebrates. The eyeball in single-lens eyes is made up of two outer layers, the scleara and the choroids. At the front of the eye, the sclera becomes the cornea, which allows light into the eye and acts as a fixed lens. The eyeball also contains the pupil, which is the hole in the center of the iris, and the retina, which contains the photoreceptor cells. Aqueous humor fills and anterior cavity of the eye, and the vitreous humor fills the posterios cavity of the eye. The retina contains rods, which are very sensitive to light, and cones, which distinguish colors. Rhodopsin is the light-absorbing pigment that triggers a signal transduction pathway that ultimately leads to sight.
5) Animal skeletons function in support, protection, and movement. Define hydrostatic skeletons, exoskeletons, and endoskeletons. Skeletal muscle is attached to bones and responsible for the movement of bones. It consists of long fibers, each of which is a single muscle cell. Each muscle fiber is a bundle of myofibrils, which in turn are composed of two kinds of myofilaments; thin filaments and thick filaments. Skeletal muscle is striated, and the basic contractile unit of the muscle is the sarcomere. The Z lines make up the border of sarcomeres, the I band is the area near the end of the sarcomere where only thin filament exists, and the A band is the entire length of the thin filaments. During muscle contraction, the length of the sarcomere is reduced. The sliding-filament model states that the thick and thin filaments slide past each other so that their degree of overlap increases. This is dependent on the interaction between the actin and myosin molecules that make up the thick and thin filaments. Muscle cells contract when simulated by a motor neuron. To stimulate muscle contraction, an action potential in a motor neuron that makes a synaptic connection with the muscle cell releases acetylcholine at the neuromuscular junction. This depolarizes the muscle cell and triggers an action potential. The action potential spreads along T tubules (transverse tubules). This changes the permeability of the sarcoplasmic reticulum to calcium ions, and the newly release calcium ions bind to troponin and cause it to move, exposing the myosin sites on actin: the muscle contracts. Fast-twitch muscle fibers are used for fast, powerful contractions. Slow-twitch muscle fibers are used for slow, long-lasting contractions.