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Exam Review Chapters 1, 2, & 3. Chapter 1 The Science of Psychology Behavior: Everything, we do that can be directly observed. Behavioral approach: an approach to psychology emphasizing the scientific study of observable behavioral responses and their environmental determinants. Biological approach: an approach to psychology focusing on the body, especially the brain and nervous system. Case study or case history: an in-depth look at a single individual. Cognitive approach: an approach to psychology emphasizing the mental processes involved in knowing: how we direct our attention, perceive, remember, think, and solve problems. Control group: The participants in an experiment who are as much like the experimental group as possible and who are treated in every way like the experimental group except for a manipulated factor, the independent variable. Correlational research: research that examines the relationships between variables, whose purpose is to examine whether and how two variables change together. Critical thinking: The process of thinking deeply and actively, asking questions, and evaluating the evidence. Dependent variable: The outcome; the factor that can change in an experiment in response to changes in the independent variable. Double-blind experiment: An experimental design in which neither the experimenter nor the participants are aware of which participants are in the experimental group and which are in the control group until the results are calculated. Evolutionary approach: An approach to psychology centered on evolutionary ideas such as adaptation, reproduction, and natural selection as the basis for explaining specific human behaviors. Experiment: A carefully regulated procedure in which the researcher manipulates one or more variables that are believed to influence some other variable. Experimental group: The participants in an experiment who receive the drug or other treatment under study—that is, those who are exposed to the change that the independent variable represents. Functionalism: James’s approach to mental processes, emphasizing the functions and purposes of the mind and behavior in the individual’s adaptation to the environment. Humanistic approach: An approach to psychology emphasizing a person’s positive qualities, the capacity for positive growth, and the freedom to choose any destiny. Hypothesis: A testable prediction that derives logically from a theory. Independent variable: A manipulated experimental factor; the variable that the experimenter changes to see what its effects are. Longitudinal design: A special kind of systematic observation, used by correlational researchers, that involves obtaining measures of the variables of interest in multiple waves over time. Mental processes: The thoughts, feelings, and motives that people experience privately but that cannot be observed directly. Natural selection: Darwin’s principle of an evolutionary process in which organisms that are best adapted to their environment will survive and produce offspring. Naturalistic observation: The observation of behavior in a real-world setting. Placebo: In a drug study, a harmless substance that has no physiological effect, given to participants in a control group so that they are treated identically to the experimental group except for the active agent. Placebo effect: The situation where participants’ expectations, rather than the experimental treatment, produce an experimental outcome. Population: The entire group about which the researcher wants to draw conclusions. Psychoanalysis: techniques involves an analyst unlocking a person's unconscious conflicts by talking with the individual about his or her childhood memories, dreams, thoughts, and feelings. Psychodynamic approach: an approach to psychology emphasizing unconscious thought, the conflict between biological drives (such as the drive for sex) and society’s demands, and early childhood family experiences. Psychology: The scientific study of behavior and mental processes. Sample: The subset of the population chosen by the investigator for study. Sociocultural approach: an approach to psychology that examines the ways in which social and cultural environments influence behavior. Structuralism: Wundt’s approach to discovering the basic elements, or structures, of mental processes. Theory: A broad idea or set of closely related ideas that attempts to explain observations and to make predictions about future observations. Validity: The soundness of the conclusions that a researcher draws from an experiment. In the realm of testing, the extent to which a test measures what it is intended to measure. Variable: Anything that can change. Wilhelm Wundt is most often regarded the "founding father" of modern psychology. He was also the founder of structuralism. William James was the founder of functionalism. J. B. Watson and B. F. Skinner believed that psychology should focus on an organism's visible interactions with the environment—that is, behaviors. Ethical Guidelines developed by the American Psychological Association include: • informed consent. • confidentiality. • deception. • debriefing. Chapter 2 The Brain and Behavior Action potential: The brief wave of positive electrical charge that sweeps down the axon. Adrenal glands: glands at the top of each kidney that are responsible for regulating moods, energy level, and the ability to cope with stress. Amygdala: An almond-shaped structure within the base of the temporal lobe that is involved in the discrimination of objects that are necessary for the organism’s survival, such as appropriate food, mates, and social rivals. Association cortex: Sometimes called association areas, the region of the cerebral cortex that is the site of the highest intellectual functions, such as thinking and problem solving. Autonomic nervous system: The body system that takes messages to and from the body’s internal organs, monitoring such processes as breathing, heart rate, and digestion. Axon The part of the neuron that carries information away from the cell body toward other cells. Basal ganglia Large neuron clusters located above the thalamus and under the cerebral cortex that work with the cerebellum and the cerebral cortex to control and coordinate voluntary movements. Brain stem The stem like brain area that includes much of the hindbrain (excluding the cerebellum) and the midbrain; connects with the spinal cord at its lower end and then extends upward to encase the reticular formation in the midbrain. Cell body The part of the neuron that contains the nucleus, which directs the manufacture of substances that the neuron needs for growth and maintenance. Central nervous system (CNS): The brain and spinal cord. Cerebral cortex: Part of the forebrain, the outer layer of the brain, responsible for the most complex mental functions, such as thinking and planning. Chromosomes: In the human cell, threadlike structures that come in 23 pairs, one member of each pair originating from each parent, and that contain DNA. Corpus callosum: The large bundle of axons that connects the brain’s two hemispheres, responsible for relaying information between the two sides. Dendrites: Treelike fibers projecting from a neuron, which receive information and orient it toward the neuron’s cell body. Deoxyribonucleic acid (DNA): A complex molecule in the cell’s chromosomes that carries genetic information. Dominant-recessive genes principle: The principle that if one gene of a pair is dominant and one is recessive, the dominant gene overrides the recessive gene. A recessive gene exerts its influence only if both genes of a pair are recessive. Endocrine system: The body system consisting of a set of glands that regulate the activities of certain organs by releasing their chemical products into the bloodstream. Forebrain: The brain’s largest division and its most forward part. Frontal lobes: The portion of the cerebral cortex behind the forehead, involved in personality, intelligence, and the control of voluntary muscles. Genes: The units of hereditary information, consisting of short segments of chromosomes composed of DNA. Genotype: An individual’s genetic heritage; his or her actual genetic material. Glands: Organs or tissues in the body that create chemicals that control many bodily functions. Glial cells: The second of two types of cells in the nervous system; glial cells (also called glia) provide support, nutritional benefits, and other functions and keep neurons running smoothly. Hindbrain: Located at the skull’s rear, the lowest portion of the brain, consisting of the medulla, cerebellum, and pons. Hippocampus: The structure in the limbic system that has a special role in the storage of memories. Hormones: Chemical messengers that are produced by the endocrine glands and carried by the bloodstream to all parts of the body. Hypothalamus: A small forebrain structure, located just below the thalamus, that monitors three pleasurable activities—eating, drinking, and sex—as well as emotion, stress, and reward. Limbic system: A set of subcortical brain structures central to emotion, memory, and reward processing. Midbrain: Located between the hindbrain and forebrain, an area in which many nerve-fiber systems ascend and descend to connect the higher and lower portions of the brain; in particular, the midbrain relays information between the brain and the eyes and ears. Motor cortex: A region in the cerebral cortex, located just behind the frontal lobes, that processes information about voluntary movement. Myelin sheath: A layer of fat cells that encases and insulates most axons. Neocortex: The outermost part of the cerebral cortex, making up 80 percent of the human brain’s cortex. Nervous system: The body’s electrochemical communication circuitry. Neural networks: Networks of nerve cells that integrate sensory input and motor output. Neurons: One of two types of cells in the nervous system; neurons are the nerve cells that handle the information-processing function. Neurotransmitters: Chemical substances that are stored in very tiny sacs within the neuron’s terminal buttons and involved in transmitting information across a synaptic gap to the next neuron. Occipital lobes: Structures located at the back of the head that respond to visual stimuli. Ovaries: Sex-related endocrine glands that produce hormones involved in women’s sexual development and reproduction. Pancreas: A dual-purpose gland under the stomach that performs both digestive and endocrine functions. Parasympathetic nervous system: The part of the autonomic nervous system that calms the body. Parietal lobes: Structures at the top and toward the rear of the head that are involved in registering spatial location, attention, and motor control. Peripheral nervous system (PNS): The network of nerves that connects the brain and spinal cord to other parts of the body. Phenotype: An individual’s observable characteristics. Pituitary gland: A pea-sized gland just beneath the hypothalamus that controls growth and regulates other glands. Plasticity: The brain’s special capacity for change. Prefrontal cortex: an important part of the frontal lobes that is involved in higher cognitive functions such as planning, reasoning, and self-control. Resting potential, The stable, negative charge of an inactive neuron. Reticular formation: A system in the midbrain comprising a diffuse collection of neurons involved in stereotyped patterns of behavior such as walking, sleeping, and turning to attend to a sudden noise. Somatic nervous system: The body system consisting of the sensory nerves, whose function is to convey information from the skin and muscles to the central nervous system about conditions such as pain and temperature, and the motor nerves, whose function is to tell muscles what to do. Somatosensory cortex: A region in the cerebral cortex that processes information about body sensations, located at the front of the parietal lobes. Stem cells: Unique primitive cells that have the capacity to develop into most types of human cells. Stress: The responses of individuals to environmental stressors. Stressors: Circumstances and events that threaten individuals and tax their coping abilities and that cause physiological changes to ready the body to handle the assault of stress. Sympathetic nervous system: The part of the autonomic nervous system that arouses the body to mobilize it for action and thus is involved in the experience of stress. Synapses: Tiny spaces between neurons; the gaps between neurons are referred to as synaptic gaps. Temporal lobes: Structures in the cerebral cortex that are located just above the ears and are involved in hearing, language processing, and memory. Testes: Sex-related endocrine glands in the scrotum that produce hormones involved in men’s sexual development and reproduction. Thalamus: The forebrain structure that sits at the top of the brain stem in the brain’s central core and serves as an important relay station. Left Hemisphere • verbal processing, speech, grammar Right Hemisphere • spatial perception • visual recognition • emotion Chapter 3 Sensation and Perception Absolute threshold: The minimum amount of stimulus energy that a person can detect. Apparent movement: The perception that a stationary object is moving. Auditory nerve: The nerve structure that receives information about sound from the hair cells of the inner ear and carries these neural impulses to the brain’s auditory areas. Binding: In the sense of vision, the bringing together and integration of what is processed by different neural pathways or cells. Binocular cues: Depth cues that depend on the combination of the images in the left and right eyes and on the way the two eyes work together. Bottom-up processing: The operation in sensation and perception in which sensory receptors register information about the external environment and send it up to the brain for interpretation. Cones: The receptor cells in the retina that allow for color perception. Convergence: A binocular cue to depth and distance in which the muscle movements in an individual’s two eyes provide information about how deep and/or far away something is. Depth perception: The ability to perceive objects three-dimensionally. Difference threshold: The degree of difference that must exist between two stimuli before the difference is detected. Feature detectors: Neurons in the brain’s visual system that respond to particular features of a stimulus. Figure-ground relationship: The principle by which we organize the perceptual field into stimuli that stand out (figure) and those that are left over (ground). Frequency theory: Theory on how the inner ear registers the frequency of sound, stating that the perception of a sound’s frequency depends on how often the auditory nerve fires. Gestalt psychology A school of thought interested in how people naturally organize their perceptions according to certain patterns. Inner ear: The part of the ear that includes the oval window, cochlea, and basilar membrane and whose function is to convert sound waves into neural impulses and send them to the brain. Kinesthetic senses: Senses that provide information about movement, posture, and orientation. Middle ear: The part of the ear that channels and amplifies sound through the eardrum, hammer, anvil, and stirrup to the inner ear. Monocular cues: Powerful depth cues available from the image in one eye, either the right or the left. Noise: Irrelevant and competing stimuli—not only sounds but also any distracting stimuli for the senses. Olfactory epithelium: The lining of the roof of the nasal cavity, containing a sheet of receptor cells for smell. Opponent-process theory: Theory stating that cells in the visual system respond to complementary pairs of red-green and blue-yellow colors; a given cell might be excited by red and inhibited by green, whereas another cell might be excited by yellow and inhibited by blue. Optic nerve: The structure at the back of the eye, made up of axons of the ganglion cells, that carries visual information to the brain for further processing. Outer ear: The outermost part of the ear, consisting of the pinna and the external auditory canal. Pain: The sensation that warns an individual of damage to the body. Papillae: Rounded bumps above the tongue’s surface that contain the taste buds, the receptors for taste. parallel processing: The simultaneous distribution of information across different neural pathways. Perception: The process of organizing and interpreting sensory information so that it makes sense. perceptual constancy: The recognition that objects are constant and unchanging even though sensory input about them is changing. perceptual set A predisposition or readiness to perceive something in a particular way. place theory: Theory on how the inner ear registers the frequency of sound, stating that each frequency produces vibrations at a particular spot on the basilar membrane. retina The multilayered light-sensitive surface in the eye that records electromagnetic energy and converts it to neural impulses for processing in the brain. Rods: The receptor cells in the retina that are sensitive to light but not very useful for color vision. selective attention: The act of focusing on a specific aspect of experience while ignoring others. semicircular canals: Three fluid-filled circular tubes in the inner ear containing the sensory receptors that detect head motion caused when an individual tilts or moves the head and/or the body. Sensation: The process of receiving stimulus energies from the external environment and transforming those energies into neural energy. sensory adaptation: A change in the responsiveness of the sensory system based on the average level of surrounding stimulation. sensory receptors: Specialized cells that detect stimulus information and transmit it to sensory (afferent) nerves and the brain. signal detection theory: An approach to perception that focuses on decision making about stimuli in the presence of uncertainty. subliminal perception The detection of information below the level of conscious awareness. Thermoreceptors: Sensory nerve endings under the skin that respond to changes in temperature at or near the skin and provide input to keep the body’s temperature at 98.6 degrees Fahrenheit. top-down processing The operation in sensation and perception, launched by cognitive processing at the brain’s higher levels, that allows the organism to sense what is happening and to apply that framework to information from the world. trichromatic theory: Theory stating that color perception is produced by three types of cone receptors in the retina that are particularly sensitive to different, but overlapping, ranges of wavelengths. vestibular sense: Sense that provides information about balance and movement. visual cortex: Located in the occipital lobe, the part of the cerebral cortex involved in vision. volley principle: Principle addressing limitations of the frequency theory of hearing, stating that a cluster of nerve cells can fire neural impulses in rapid succession, producing a volley of impulses. Weber’s law: The principle that two stimuli must differ by a constant minimum percentage (rather than a constant amount) to be perceived as different.

bio Genetics is the study of heredity and how traits are passed from parents to offspring. Gregor Mendel is known as the “Father of Genetics.” Why did Mendel use pea plants? * Easy to grow * Short generation time * Many visible traits * Can self-pollinate or cross-pollinate * Produce many offspring Examples of traits studied: * Flower colour * Seed shape * Plant height ⸻ VOCABULARY Gene * A segment of DNA that controls a trait. Allele * Different forms of the same gene. Example: P = purple flowers p = white flowers Dominant Allele * Expressed whenever it is present. * Represented by a capital letter. Example: P = purple Recessive Allele * Only expressed when two copies are present. * Represented by a lowercase letter. Example: p = white Genotype * Genetic makeup of an organism. Examples: PP Pp pp Phenotype * Physical appearance of an organism. Examples: Purple flower White flower Homozygous * Two identical alleles. Examples: PP pp Heterozygous * Two different alleles. Example: Pp Pure Breeding * Homozygous for a trait. Gamete * Sex cell (sperm or egg). ⸻ MENDEL’S LAWS Law of Dominance * A dominant allele masks a recessive allele. Example: Pp = Purple flower Law of Segregation * Alleles separate during gamete formation. * Each gamete receives only one allele. Example: Parent = Pp Gametes: P p Law of Independent Assortment * Different genes assort independently during meiosis. ⸻ MONOHYBRID CROSSES A monohybrid cross studies one trait. Example: P = Purple p = White Cross: Pp × Pp Punnett Square INCOMPLETE DOMINANCE Neither allele completely dominates. Example: Snapdragons RR = Red WW = White RW = Pink Cross: RW × RW Genotype Ratio: 1 RR : 2 RW : 1 WW Phenotype Ratio: 1 Red : 2 Pink : 1 White CODOMINANCE Both alleles are expressed equally. Example: AB Blood Type Genotype: IAIB Phenotype: AB MULTIPLE ALLELES More than two alleles exist in a population. Example: ABO Blood Group Alleles: IA IB i BLOOD TYPES Type A Genotypes: IAIA or IAi Type B Genotypes: IBIB or IBi Type AB Genotype: IAIB Type O Genotype: ii Can Type A and Type B Parents Have a Type O Child? Yes. If: Father = IAi Mother = IBi Possible Blood Types: AB A B O CELL CYCLE Purpose: * Growth * Repair * Replacement of cells Stages: G1 S G2 Mitosis Cytokinesis INTERPHASE G1 Phase Cell grows and carries out normal functions. S Phase DNA replication occurs. G2 Phase Cell prepares for division. MITOSIS Purpose: Growth and repair. Produces: 2 genetically identical diploid cells. PROPHASE Events: * Chromosomes condense * Nuclear membrane disappears * Nucleolus disappears * Spindle fibres form METAPHASE Events: * Chromosomes line up at the equator ANAPHASE Events: * Sister chromatids separate TELOPHASE Events: * Nuclear membranes reform * Chromosomes uncoil CYTOKINESIS Division of the cytoplasm. Animal Cells: Cleavage furrow forms. Plant Cells: Cell plate forms. CHROMOSOME STRUCTURE Chromosome consists of: * Two sister chromatids * One centromere DIPLOID VS HAPLOID Diploid (2n) * Two sets of chromosomes * Human body cells * 46 chromosomes Haploid (n) * One set of chromosomes * Human gametes * 23 chromosomes HOMOLOGOUS CHROMOSOMES Chromosome pairs that: * Carry the same genes * One comes from the mother * One comes from the father Humans have 23 homologous pairs. MEIOSIS Purpose: Produce gametes. Produces: 4 genetically unique haploid cells. MEIOSIS I Separates homologous chromosomes. CROSSING OVER Occurs during Prophase I. Definition: Exchange of DNA between homologous chromosomes. Importance: Creates genetic variation. RANDOM ASSORTMENT Occurs during Metaphase I. Definition: Homologous pairs line up randomly. Importance: Creates unique chromosome combinations. MEIOSIS II Separates sister chromatids. MITOSIS VS MEIOSIS Mitosis * 2 cells produced * Diploid * Genetically identical * Growth and repair Meiosis * 4 cells produced * Haploid * Genetically different * Produces gametes NONDISJUNCTION Failure of chromosomes to separate properly during meiosis. Can result in extra or missing chromosomes. DOWN SYNDROME Cause: Extra chromosome 21. Chromosome Number: 47 Usually caused by nondisjunction during meiosis. DNA DNA = Deoxyribonucleic Acid Shape: Double Helix Function: Stores genetic information. NUCLEOTIDE Three Components: * Phosphate Group * Deoxyribose Sugar * Nitrogenous Base NITROGENOUS BASES Adenine (A) Thymine (T) Cytosine (C) Guanine (G) COMPLEMENTARY BASE PAIRING A pairs with T C pairs with G DNA REPLICATION Purpose: Make identical copies of DNA. Location: Nucleus Result: Two identical DNA molecules. TRANSCRIPTION Purpose: Create mRNA from DNA. Location: Nucleus DNA → mRNA Remember: RNA uses Uracil (U) instead of Thymine (T). TRANSLATION Purpose: Make proteins. Location: Ribosome mRNA is read and amino acids are joined together to form a protein. MUTATIONS A mutation is a change in DNA sequence. Types: * Deletion * Duplication * Inversion * Translocation DELETION DNA segment removed. DUPLICATION DNA segment repeated. INVERSION DNA segment reversed. TRANSLOCATION DNA segment moves to another chromosome. SEX-LINKED TRAITS Traits located on sex chromosomes. Most are located on the X chromosome. RED-GREEN COLOUR BLINDNESS Inheritance: X-linked recessive. XC = Normal Vision Xc = Colour Blind Male: XcY Colour blind boys inherit the allele from their mother because fathers pass a Y chromosome to their sons. TAY-SACHS DISEASE Cause: Missing enzyme that breaks down lipids in nerve cells. Inheritance: Autosomal recessive. Treatment: No cure currently available. SICKLE CELL ANEMIA Cause: Mutation in hemoglobin gene. Effects: * Sickle-shaped red blood cells * Reduced oxygen transport * Blocked blood vessels Inheritance: Autosomal recessive. HUNTINGTON’S DISEASE Cause: Dominant mutation. Effects: * Nervous system degeneration * Loss of motor control * Cognitive decline Inheritance: Autosomal dominant. KARYOTYPE A photograph of chromosomes arranged in pairs. Used to: * Determine sex * Detect chromosome abnormalities * Diagnose genetic disorders PEDIGREE A family tree used to track inheritance patterns. Symbols: Square = Male Circle = Female Shaded = Has trait CLONING Producing genetically identical organisms. Uses: * Research * Agriculture * Medicine * Conservation GENETIC COUNSELLING Provides information about: * Inherited disorders * Family risk * Testing options AMNIOCENTESIS Prenatal test in which amniotic fluid is sampled and fetal cells are analyzed. Can detect: * Genetic disorders * Chromosomal disorders GMOs Genetically Modified Organisms. Definition: Organisms whose DNA has been altered through biotechnology. Advantages: * Increased crop yield * Disease resistance * Pest resistance Disadvantages: * Ethical concerns * Environmental concerns DNA REPLICATION → TRANSCRIPTION → TRANSLATION DNA (Nucleus) ↓ Replication DNA Copy DNA ↓ Transcription mRNA mRNA ↓ Translation Protein Final Product: Protein RESPIRATORY SYSTEM Function: * Brings oxygen into the body * Removes carbon dioxide * Works with the circulatory system to supply cells with oxygen Why do organisms require oxygen and produce carbon dioxide? Oxygen is required for cellular respiration. Cellular Respiration: Glucose + Oxygen → Energy (ATP) + Carbon Dioxide + Water Cells use oxygen to release energy from food. Carbon dioxide is produced as a waste product and must be removed. ⸻ PATHWAY OF AIR Nasal Cavity ↓ Pharynx ↓ Larynx ↓ Trachea ↓ Bronchi ↓ Bronchioles ↓ Alveoli ⸻ NASAL CAVITY Functions: * Warms air * Moistens air * Filters air Nasal Hairs: * Trap large particles Mucus: * Traps dust and microorganisms Blood Capillaries: * Warm incoming air ⸻ PHARYNX Common passageway for: * Air * Food Also called the throat. ⸻ UVULA Functions: * Prevents food from entering nasal cavity * Helps with speech ⸻ EPIGLOTTIS Functions: * Covers trachea during swallowing * Prevents choking ⸻ LARYNX Also called the voice box. Contains vocal cords. ⸻ TRACHEA Also called the windpipe. Contains cartilage rings that prevent collapse. Lined with: * Cilia * Mucus ⸻ CILIA Tiny hair-like structures. Function: * Sweep mucus upward toward throat ⸻ BRONCHI Two branches of the trachea leading to lungs. Right Bronchus → Right Lung Left Bronchus → Left Lung ⸻ BRONCHIOLES Smaller branches inside lungs. Lead to alveoli. ⸻ ALVEOLI Tiny air sacs. Site of gas exchange. Adaptations: * Thin walls * Moist surface * Large surface area * Rich blood supply Gas Exchange: Oxygen moves: Alveoli → Blood Carbon Dioxide moves: Blood → Alveoli By diffusion. ⸻ BREATHING MECHANICS Two main muscles: 1. Diaphragm 2. Intercostal Muscles ⸻ INHALATION (INSPIRATION) Diaphragm: * Contracts * Moves downward Intercostal Muscles: * Contract * Lift ribs upward Result: * Chest cavity volume increases * Pressure decreases * Air enters lungs ⸻ EXHALATION (EXPIRATION) Diaphragm: * Relaxes * Moves upward Intercostal Muscles: * Relax Result: * Chest cavity volume decreases * Pressure increases * Air leaves lungs ⸻ MEDULLA OBLONGATA Located in the brainstem. Function: * Controls breathing rate Responds to: * Carbon dioxide levels More CO₂: * Faster breathing Less CO₂: * Slower breathing ⸻ LUNG VOLUMES Tidal Volume * Normal amount of air breathed in and out Inspiratory Reserve Volume * Extra air inhaled after normal breath Expiratory Reserve Volume * Extra air exhaled after normal breath Residual Volume * Air remaining in lungs after maximum exhalation Vital Capacity * Maximum amount of air exhaled after deepest breath Total Lung Capacity * Total amount of air lungs can hold ⸻ CIRCULATORY SYSTEM Functions: * Transport oxygen * Transport nutrients * Remove wastes * Maintain homeostasis * Transport hormones Humans have a CLOSED circulatory system. Blood remains inside vessels. ⸻ BLOOD VESSELS ARTERIES Function: * Carry blood away from heart Characteristics: * Thick walls * High pressure * Small lumen * No valves Usually oxygen-rich Exception: Pulmonary artery ⸻ VEINS Function: * Carry blood toward heart Characteristics: * Thin walls * Low pressure * Large lumen * Valves present Usually oxygen-poor Exception: Pulmonary vein ⸻ CAPILLARIES Smallest blood vessels. Functions: * Gas exchange * Nutrient exchange * Waste exchange Walls are one cell thick. ⸻ HEART STRUCTURE Blood Flow: Body ↓ Vena Cava ↓ Right Atrium ↓ Right Ventricle ↓ Pulmonary Artery ↓ Lungs ↓ Pulmonary Vein ↓ Left Atrium ↓ Left Ventricle ↓ Aorta ↓ Body ⸻ HEART CHAMBERS Right Atrium * Receives deoxygenated blood Right Ventricle * Pumps blood to lungs Left Atrium * Receives oxygenated blood Left Ventricle * Pumps blood to body ⸻ SEPTUM Wall separating left and right sides of heart. Prevents mixing of blood. ⸻ HEART VALVES Function: * Prevent backflow of blood Types: Atrioventricular (AV) Valves Pulmonary Semilunar Valve Aortic Semilunar Valve ⸻ SA NODE Sinoatrial Node Known as: * Natural pacemaker Initiates heartbeat. ⸻ AV NODE Atrioventricular Node Receives signal from SA node. Delays impulse slightly. Allows ventricles to fill before contraction. ⸻ BLOOD Components: 1. Plasma 2. Red Blood Cells 3. White Blood Cells 4. Platelets ⸻ PLASMA Liquid component of blood. Functions: * Transport nutrients * Transport hormones * Transport wastes ⸻ RED BLOOD CELLS (ERYTHROCYTES) Function: * Carry oxygen Contain: * Hemoglobin ⸻ HEMOGLOBIN Protein in red blood cells. Function: * Binds oxygen Allows oxygen transport. ⸻ WHITE BLOOD CELLS (LEUKOCYTES) Function: * Fight infection * Defend body Part of immune system. ⸻ PLATELETS Function: * Blood clotting Prevent blood loss. ⸻ BLOOD PRESSURE Force of blood against artery walls. Measured using: Sphygmomanometer Example: 120/80 120 = Systolic Pressure 80 = Diastolic Pressure ⸻ SYSTOLIC PRESSURE Pressure when heart contracts. ⸻ DIASTOLIC PRESSURE Pressure when heart relaxes. ⸻ HYPERTENSION High blood pressure. Can increase risk of: * Stroke * Heart attack * Kidney disease ⸻ STROKE VOLUME Amount of blood pumped per heartbeat. ⸻ CARDIAC OUTPUT Amount of blood pumped per minute. Formula: Cardiac Output = Heart Rate × Stroke Volume ⸻ ECG Electrocardiogram Measures electrical activity of heart. Used to detect: * Irregular heartbeat * Heart damage ⸻ PULMONARY CIRCULATION Heart → Lungs → Heart Purpose: * Oxygenate blood ⸻ SYSTEMIC CIRCULATION Heart → Body → Heart Purpose: * Deliver oxygen to tissues ⸻ HOMEOSTASIS DURING EXERCISE Body responds by: * Increasing heart rate * Increasing breathing rate * Increasing cardiac output * Redirecting blood to muscles * Sweating to cool body Purpose: Maintain stable internal conditions. ⸻ DIGESTIVE SYSTEM Functions: * Break down food * Absorb nutrients * Eliminate waste ⸻ DIGESTIVE TRACT Mouth ↓ Pharynx ↓ Esophagus ↓ Stomach ↓ Small Intestine ↓ Large Intestine ↓ Rectum ↓ Anus ⸻ MECHANICAL DIGESTION Physical breakdown of food. Examples: * Chewing * Churning ⸻ CHEMICAL DIGESTION Chemical breakdown of food using enzymes. Examples: * Amylase * Pepsin ⸻ SALIVA Functions: 1. Moistens food 2. Contains amylase Amylase begins carbohydrate digestion. ⸻ TONGUE Functions: 1. Forms bolus 2. Pushes food for swallowing ⸻ ESOPHAGUS Moves food to stomach. Uses: Peristalsis ⸻ PERISTALSIS Wave-like muscular contractions. Move food through digestive tract. ⸻ STOMACH Functions: * Stores food * Mixes food * Begins protein digestion Produces: * HCl * Pepsin * Mucus ⸻ HCl Hydrochloric Acid Functions: * Kills bacteria * Activates pepsin ⸻ PEPSIN Function: * Digests proteins ⸻ MUCUS Function: * Protects stomach lining ⸻ CHYME Semi-liquid food mixture leaving stomach. ⸻ HEARTBURN Cause: Stomach acid enters esophagus. Usually caused by weakened cardiac sphincter. ⸻ SMALL INTESTINE Main site of: * Digestion * Absorption Adaptations: * Long length * Folds * Villi * Microvilli Large surface area increases absorption. ⸻ DUODENUM First section. Functions: * Receives bile * Receives pancreatic enzymes * Most chemical digestion ⸻ JEJUNUM Main nutrient absorption. ⸻ ILEUM Final nutrient absorption. ⸻ VILLI Finger-like projections. Function: Increase surface area. ⸻ LIVER Functions: * Produces bile * Processes nutrients * Detoxifies blood ⸻ GALL BLADDER Functions: * Stores bile * Releases bile into small intestine ⸻ PANCREAS Functions: * Produces digestive enzymes * Produces bicarbonate ⸻ BILE Function: Emulsifies fats. Breaks large fat droplets into smaller droplets. Makes fat digestion easier. ⸻ DIGESTION OF CARBOHYDRATES Mouth: * Amylase begins digestion Small Intestine: * Pancreatic amylase continues digestion End Product: Glucose ⸻ DIGESTION OF PROTEINS Stomach: * Pepsin begins digestion Small Intestine: * Trypsin continues digestion End Product: Amino Acids ⸻ DIGESTION OF LIPIDS Small Intestine: * Bile emulsifies fats * Lipase digests fats End Product: Fatty Acids + Glycerol ⸻ EVOLUTION Evolution: Change in populations over time. Individuals do NOT evolve. Populations evolve. ⸻ DARWIN Proposed: Natural Selection Book: On the Origin of Species ⸻ WALLACE Independently developed theory of natural selection. ⸻ LAMARCK Proposed: Inheritance of acquired characteristics Example: Giraffes stretch necks and pass longer necks to offspring. This theory is incorrect. ⸻ NATURAL SELECTION Requirements: 1. Variation 2. Overproduction 3. Competition 4. Differential Survival 5. Reproduction Result: Adaptation ⸻ ADAPTATION Inherited characteristic that increases survival and reproduction. ⸻ SELECTIVE ADVANTAGE A characteristic that improves survival or reproduction. Example: Antibiotic resistance ⸻ SELECTIVE PRESSURE Environmental factor that influences survival. Examples: * Predators * Disease * Climate * Competition ⸻ VARIATION Differences among individuals in a population. Sources: * Mutation * Crossing Over * Random Assortment ⸻ MUTATION Ultimate source of new alleles. Creates genetic variation. ⸻ FOSSIL Preserved remains or traces of organisms. ⸻ FOSSIL RECORD Collection of fossils showing evolutionary history. Provides evidence for evolution. ⸻ RADIOACTIVE DATING Uses radioactive isotopes to determine fossil age. ⸻ UNIFORMITARIANISM Proposed by Lyell. Earth changes gradually over long periods of time. ⸻ CATASTROPHISM Proposed by Cuvier. Earth shaped by sudden catastrophic events. ⸻ BIOGEOGRAPHY Study of species distribution around Earth. Provides evidence for evolution. ⸻ EMBRYOLOGY Study of embryos. Similar embryos suggest common ancestry. ⸻ HOMOLOGOUS STRUCTURES Same evolutionary origin. Different functions. Example: Human arm Whale flipper Bat wing Evidence of common ancestry. ⸻ ANALOGOUS STRUCTURES Different origins. Same function. Example: Bird wing Insect wing Not evidence of close ancestry. ⸻ VESTIGIAL STRUCTURES Structures with little or no function. Examples: * Human appendix * Whale pelvis Evidence of evolution. ⸻ MIMICRY One species resembles another. Example: Syrphid fly resembles wasp. Provides protection. ⸻ ARTIFICIAL SELECTION Humans select traits. Examples: * Dog breeding * Crop breeding ⸻ DIRECTIONAL SELECTION One extreme phenotype favored. Graph shifts in one direction. ⸻ STABILIZING SELECTION Average phenotype favored. Extremes selected against. ⸻ DISRUPTIVE SELECTION Both extremes favored. Middle selected against. ⸻ GENETIC DRIFT Random change in allele frequencies. Most significant in small populations. ⸻ FOUNDER EFFECT Small group starts new population. Different allele frequencies from original population. ⸻ BOTTLENECK EFFECT Population drastically reduced. Loss of genetic variation. ⸻ GENE FLOW Movement of alleles between populations. Occurs through migration. ⸻ NON-RANDOM MATING Individuals choose specific mates. Can reduce variation. ⸻ SPECIES A group of organisms that can interbreed in nature and produce fertile offspring. ⸻ SPECIATION Formation of new species. ⸻ ALLOPATRIC SPECIATION Requires: Geographic isolation Example: Mountain separates populations. ⸻ SYMPATRIC SPECIATION Occurs without geographic isolation. ⸻ PRE-ZYGOTIC ISOLATION Prevents fertilization. Examples: * Different mating seasons * Different mating songs * Different habitats ⸻ POST-ZYGOTIC ISOLATION Occurs after fertilization. Example: Sterile hybrids Example: Mule DIVERSITY Prokaryotes vs Eukaryotes PROKARYOTES * No nucleus * No membrane-bound organelles * Circular DNA * Smaller * Examples: Eubacteria, Archaebacteria EUKARYOTES * Nucleus present * Membrane-bound organelles * Linear chromosomes * Larger * Examples: Protists, Fungi, Plants, Animals Three Differences: 1. Nucleus vs no nucleus 2. Organelles vs no organelles 3. Larger vs smaller ⸻ Taxonomy Kingdom Phylum Class Order Family Genus Species Mnemonic: King Philip Came Over For Good Soup ⸻ Binomial Nomenclature Genus + Species Example: Homo sapiens Rules: * Genus capitalized * Species lowercase * Italicized Purpose: * Universal naming system * Avoids confusion * Shows relationships ⸻ Dichotomous Key Used to identify organisms using paired choices. Example: 1a Has wings → Step 2 1b No wings → Step 3 ⸻ Six Kingdoms 1. Archaebacteria 2. Eubacteria 3. Protista 4. Fungi 5. Plantae 6. Animalia ⸻ VIRUSES Virus Structure: * DNA or RNA * Capsid * Attachment proteins * Sometimes envelope Why Viruses Are Not Living: * Not made of cells * Cannot reproduce independently * No metabolism * Need host cell ⸻ DNA Virus vs RNA Virus DNA Virus: * Contains DNA * More stable RNA Virus: * Contains RNA * Mutates faster ⸻ Lytic Cycle Attachment ↓ Penetration ↓ Replication ↓ Assembly ↓ Lysis Host cell bursts. ⸻ Lysogenic Cycle Attachment ↓ Penetration ↓ Integration into host DNA ↓ Host reproduces ↓ Virus DNA copied Cell survives initially. ⸻ ARCHAEBACTERIA Characteristics: * Prokaryotic * Unicellular * Extreme environments Three Groups: Methanogens * Produce methane Halophiles * Salt-loving Thermoacidophiles * Hot acidic environments ⸻ EUBACTERIA Characteristics: * Prokaryotic * Peptidoglycan cell wall * Binary fission Examples: * E. coli * Streptococcus ⸻ Binary Fission DNA Replication ↓ Cell Growth ↓ Cell Division ↓ Two Identical Cells ⸻ Conjugation DNA transfer through pilus. Importance: * Genetic variation * Antibiotic resistance ⸻ Antibiotic Resistance Mutation ↓ Antibiotic kills susceptible bacteria ↓ Resistant bacteria survive ↓ Resistant bacteria reproduce Natural Selection ⸻ PROTISTS Characteristics: * Eukaryotic * Mostly unicellular * Aquatic Three Groups: Animal-like * Amoeba * Paramecium Plant-like * Algae * Euglena Fungus-like * Slime molds ⸻ Amoeba * Uses pseudopods * Phagocytosis ⸻ Algae * Photosynthetic * Oxygen producer ⸻ Euglena * Chloroplasts * Flagellum * Photosynthesis * Can also feed heterotrophically ⸻ Malaria Cause: Plasmodium Kingdom: Protista ⸻ FUNGI Characteristics: * Eukaryotic * Heterotrophic * Chitin cell walls * Reproduce with spores Examples: * Mushrooms * Mold * Yeast ⸻ External Digestion Release enzymes ↓ Digest food outside body ↓ Absorb nutrients ⸻ Fungi vs Plants FUNGI * Heterotrophic * Chitin * No chloroplasts PLANTS * Autotrophic * Cellulose * Chloroplasts ⸻ PLANTS Biodiversity vs Monoculture BIODIVERSITY * Many species * Stable ecosystem * Disease resistance MONOCULTURE * One crop species * Low diversity * Disease risk ⸻ Bryophytes Definition: Nonvascular plants Examples: * Mosses * Liverworts Characteristics: * No xylem * No phloem * Need water for reproduction ⸻ Vascular Plants Contain: * Xylem * Phloem ⸻ Xylem Function: Water and minerals Direction: Roots → Leaves ⸻ Phloem Function: Sugars Direction: Throughout plant ⸻ Alternation of Generations Sporophyte (2n) ↓ meiosis Spores (n) ↓ Gametophyte (n) ↓ Gametes ↓ fertilization Zygote (2n) ↓ Sporophyte ⸻ Moss Life Cycle Spores ↓ Gametophyte ↓ Egg + Sperm ↓ Zygote ↓ Sporophyte ↓ Capsule ↓ Spores Know: * Capsule * Sporophyte * Gametophyte * Spores ⸻ Fern Life Cycle Fern ↓ Sori ↓ Spores ↓ Prothallus ↓ Gametes ↓ Fertilization ↓ Young Fern Know: * Frond * Sori * Sporangia * Prothallus ⸻ Gymnosperms Characteristics: * Naked seeds * Cones * Wind pollination * Evergreen Examples: * Pine * Spruce * Fir ⸻ Angiosperms Characteristics: * Flowers * Fruit * Seeds enclosed Examples: * Apple tree * Rose * Maple ⸻ Flower Structure Anther * Produces pollen Pollen Grain * Male gamete Stigma * Receives pollen Style * Connects stigma and ovary Ovary * Contains ovules Ovule * Female gamete Petals * Attract pollinators ⸻ Plant Tissues Meristematic * Growth Dermal * Protection Ground * Photosynthesis * Storage Vascular * Transport ⸻ Leaf Structure Blade * Main leaf surface Petiole * Connects leaf to stem Cuticle * Reduces water loss Palisade Mesophyll * Photosynthesis Spongy Mesophyll * Gas exchange Veins * Xylem + Phloem ⸻ Stomata Openings in leaves. Functions: * Gas exchange * Water loss ⸻ Guard Cells Control opening and closing of stomata. ⸻ Transpiration Water loss from leaves. Functions: * Pulls water upward * Cools plant * Moves minerals ⸻ Simple vs Compound Leaves Simple: * One blade Compound: * Multiple leaflets ⸻ Monocots vs Dicots MONOCOTS * 1 cotyledon * Parallel veins * Fibrous roots * Flower parts in 3s Examples: Corn Grass DICOTS * 2 cotyledons * Net veins * Taproot * Flower parts in 4s or 5s Examples: Bean Maple ⸻ Seeds Contain: * Embryo * Stored food * Seed coat Functions: * Protection * Survival * Dispersal ⸻ Seed Dispersal Wind * Dandelion Water * Coconut Animals * Burrs Explosive * Touch-me-not ⸻ Fruit vs Vegetable Fruit: * Comes from ovary * Contains seeds Examples: Tomato Apple Pepper Vegetable: * Root, stem, leaf, or flower Examples: Carrot Celery Broccoli ⸻ Factors Affecting Plant Growth 1. Light 2. Water 3. Carbon dioxide 4. Temperature 5. Soil nutrients 6. Oxygen 7. Soil pH 8. Space 9. Pollinators 10. Disease and pests