Biology Exam Study Guide
Transcript of Biology Exam Study Guide
Chapter 18 Taxonomy:
o 3 Domainso Bacteriao Archaeao Eukarya
o Domain Archaea- Archeobacteriao Characteristics:
Live in extreme environments Love salt and acid Prokaryotes Unicellular Autotrophs Have a cell wall Immobile Mitosis
o Domain Bacteria- Eubacteriao Characteristics:
Most go without oxogen Prokaryotes Unicellular Autotrophs Cell wall has peptidoglycan Immobile Asexual Ex: regular bacteria
o Domain Eukarya o Has 4 kingdoms
Kingdom Protistia Not a plant, animal, or a fungus Eukaryotes Some are unicellular and others multicellular Autotrophs, or Hetertrophs Mobile, or immobile Most are sexual Ex: Amebas, and Paramecium
Kingdom Fungi They grow wildly, and need moist areas
Multicellular Eukaryotes Absorptive heterotroph They have chitin in cell walls Immobile Ex: mushrooms, and mold
Kingdom Planti Photosynthetic Eukaryotes Multicellular Autotrophs Immobile Sexual and asexual Have cell walls Ex: weeds, flowers, and catus
Kingdom Animalia Eukaryotes Multicellular Heterotrophs No cell wall Mobile Sexual Ex: sponges, worms, insects, fishes, mammals
o Binomial Nomenclature- is a two part scientific name given to a species
The first name is the genus The second name is the family
Chapter 19 Bacteria:
o Prokaryotes: Single celled organisms Smallest and the most common Has 2 domains with 2 kingdoms
Bacteria- Eubacteria Achae- Achaebacteria
Kingdom Eubacteria Has peptidoglycan in cell wall Can live anywhere
Kingdom Archaebacteria Live in oxygen free environment No peptidoglycan in cell wall
Shapes: Bacilli- Rod shaped Cocci- Spherical Spirilla- Spiral and corkscrew
o Strepto- chainso Staphlo- clusters
Movement: Flagella- whip-like structures Immobile Slime secretion
Metabolism: Autotrophs- Obtain their own energy Photoautotrophic- obtain their energy from the sun
o Cyanobacteria Chemoautotrophs- take in energy directly from
organic molecules.o They use ammoniao Hydrogen sulfideo Hitriteso Sulfuro Irono Live in the deep darkness of the ocean
Heterotrophs- organisms that obtain energy from the food it consumes
o Most prokaryotes are Heterotrophs Photo heterotrophic- use the sunlight for energy, but
they also need to take in organic material as a carbon source
o Ex: Venus flytrap Obligate Aerobes- organisms that require a constant
supply of oxygen Obligate Anaerobes- must live in the absence of
oxygen.o Food Poisoning (botchism)
Facultative Anaerobes- they can live with or without oxygen
o Can live anywhereo Benefits of Bacteria in nature:
Decomposers Nitrogen Fixers Genetically engineered bacteria clean oil spills Make medicines Preservatives Antibiotics- medicines that block the growth and
reproduction of bacteria Ex: Penicillin
Help our bodies with digestiono Harmful Bacteria
Spoil food Cause disease by breaking down tissue Pathogens- bacteria that cause disease.
o Viruses
Virus- a particle that has a core of nucleic acid and surrounded by a protein cap.
Capsid- protein coat that is around the cop of the virus Bacteriophage- they are viruses that attack bacteria The Lytic Cycle:
Viruses stick to the host by adsorption Viruses inject their DNA into the host Once inside the host the viral DNA replicates The host explodes releasing the particles
The Lysogenic Cycle- a host cell makes copies of the virus. Retrovirus- Viruses that have RNA as their genetic code
They use reverse transcriptase- RNA to DNA Prions- protein infectious particle
Cause brain disease Viroids- they infect plants, and stop growth of plants.
Chapter 20 Protists
o Classifications of Protists Animal like Protists- Protozoans Plant like Protists- Algae Fungus like Protists- Slime Molds
o Animal Like Protists Heterotrophs Have 4 phlya based on means of movement Zoomastigina- Zooflagellates
Move by 1-2 flagella Live in water Parasites
Sarcodina- Sarcodines Move by pseudopods Amoeboid motion- cytoplasm ejects Phagocytosis- engulfing by amoeboid motion Ex: Foraminiferns- makes chalk
Ciliophora- Cilitates Move by cilia Ex: Paramecium
Sporazoa- Sporozoans Immobile Parasites Ex: plasmodium- causes malaria
o Plantlike Protists Phlya Euglenophyta- Eulgenophtes
2 flagella
No cell wall Eyespots Pellicle Ex: Euglena
Phlya Chrysophyta- Chrsophytes Bright yellow colored chloroplasts Ex: yellow and brown algae Store food as oil not starch
Phlya Bacillariophyta- Diatoms Have silicon in cell walls Ex: Diatoms
Phlya Pyrrophyta- Dinoflagellates Luminescent Ex: Red tide Photosynthetic or heterotrophic
o Algae Rhodophyta- Red Algae
Ex: Coralline Phaecophyta- Brown Algae
Ex: Sargassum Cholorophyta- Green Algae
Photosynthetic pigments in cell wallso Fungus like Protists
Acrasiomycota- cellular slime molds Work together as one organism Ex: Cellular slime molds
Myxomcota- Acellular slime molds Single structures with many nuclei Ex: acellular slime molds, fungus
Oomycota- water molds Decomposers Ex: Phtophthora infestans- attacks potatoes Responsible for the Potato Famine
Chapter 21 Fungus:
o Structures of Fungus:o Stolons- stem like hyphaeo Rhizoids- anchor the fungus to the groundo Hyphae- this filamentso Myecilium- composed of many hyphae tangled together by a
thick mass.
o 4 Phyla of fungi- they are classified by their spore-producing structures.
o Zygomycota- Common Molds Ex: cheese, bread, and meat molds
o Ascomycota- Sacfungi Ascus- a reproductive structure that contain spores. Ex: Saccharoymces- yeast Reproduce by budding
o Basidomcota- Club Fungi Mushrooms- fruiting body Gills house the spores
o Deuteromycota- Imperfect Fungi They haven’t yet had a reproduction phase of their life Ex: Penicillum notatum- grows in fruit and is the source for
penicillino All fungi are heterotrophico They are Saprobes- organisms that obtain their energy from
decaying mattero Plant parasites
Corn smut Mildew
o Human parasites Athlete’s foot Yeast infections
o Mycorrhizae- when plants and fungi use each others roots 80% of plants use this It is necessary for plant growth
o Lichens- symbiotic relationship between fungus and plants Not single celled organisms
o Beneficial uses: Decomposers Produce medicines
Ex: penicillin Food Fermentation in baking and brewing
Chapters 22- 25 Plants
o 2 major plant groups: Bryophytes Tracheophytes
o Bryohpytes- lack vascular tissue to carry water and minerals Lack true root, stem, and leaves Get water through rhizoids
Have a waxy covering called Chitin to reduce water loss Groups of Bryohpytes:
Mosses Liverworts Hornworts
Used to make peat mosso Tracheophytes- contain vascular tissue (xylem and phloem)
Have leaves, roots, and stem 2 groups of Tracheophytes:
Seedless plants Seed plants
Seedless Vascular plants Club mosses
o Grow in damp woods and produce spores called strobili
Horsetails- also produce strobili Ferns – have underground stems called rhizoids
Seed Plants Found everywhere Cones or Flowers Pollination Protect embryos by seeds 2 main groups
o Gymnosperms and Angiosperms Gymnosperms- “cone bearers”- produce seeds that
are exposedo Cycads- palm like plantso Gingkoes- oldest seed plants
Gingko biloba o Conifers
Most are evergreens Pollen is carried by wind, animals,
insects, and rain Angiosperms- are flowering plants
o Seeds are protected by fruito Reproductive organs in flowerso 2 groups of angiosperms:
Dicots Monocots
o Dicots- plants whose seeds contain 2 cotyledons
Ex: bean, and peanut plant Broad leaves with branched veins Vascular bundles arranged in a circle
o Monocot- plants who contain 1 cotyledon “seed leaf” that stores energy for the embryo
Long narrow leaves with parallel veins
Xylem and Phloem tissue are scattered throughout in vascular bundles through the stem
Ex: corn Flower Parts
Female Structures: Carpelo Stigma- sticky top parto Style- supports the stigmao Ovary- at the base of the style where eggs are
producedo Eggs (ovules) - female reproductive cells.
Male Structures: Stameno Anther- top part where pollen is producedo Filament- supports the anthero Petals- colored parts which attract pollinators
or insectso Sepals- tiny, green leaves at the base of the
flower that surrounds and protects the bud.o Epiphytes- not parasites, they live on other plants but have there
own source of energy Ex: Spanish moss
o Roots- absorption of nutrients Anchor plants into the soil Storage of food 2 root systems:
Taproot- one main root Fibrous- frayed roots
o Stems- produce leaves and flowers, support the plant, transport nutrients and water, and the storage of food.
Types of Stems: Herbaceous- soft green and juicy
o Supported by water pressure Woody
o Bark protects the stem from water loss.o Made by xylem cells
Buds- protect the meristem the makes new stems Nodes- places on the stem that leaves are attached
o Leaves- the structure of photosynthesiso Pg 595o Transpiration- loss of water through the leaves
Chapter 26-29 Invertebrates
o Phylum Porifera- sponges (pore bearer)o Aquatic and Marine
o Ex: spongeso Filter feederso Simplest animalso No bilateral symmetryo Sessile- no movemento Ocsulum
o Phylum Cnidaria- Cnidarians( stinging cells)o Aquatic and some marineo Ex: jellyfish, coral, sea anonomies, Hydriao Nerve neto One moutho Tentacles
o Phylum Platyhelminthes- Flatworms ( flatworms)o Terrestrial and Aquatico Ex: Tapeworms, flukeso Hermaphroditico 2 eyespots
o Phylum Nematoda- Round worms (threadlike)o Parasitico Ex: Heartworms, parasites, pin wormso Bilateral symmetryo Intestinal openingso Hermaphrodites
o Phylum Anneldia- segmented worms (ring segments)o Terrestrial and aquatico Ex: leaches, earthwormso Parasitico 2 openings mouth and anuso Circulatory systemo Cuticle skino Setae
o Phylum Mollusca- Molluscs (Mollusks)o Terrestrial and aquatico Ex: slugso Soft bodieso Mantle- folded tissue
o Phylum Arthropoda- Arthropods (jointed appendages)o All habitats water and lando Ex: insects, spiderso 3 pairs of legs
o Phylum Echinodermata- Echinoderms (spinney skin)o Marineo Ex: starfish, sand dollars, sea cucumberso Radial symmetry
o Spinned skino Water vascular systemo Regenerates limbs
o Body Symmetry:o Anterior- front regiono Posterior- hind endo Dorsal- top or back sideo Ventral- Stomacho Lateral- next too, or side
Chapters 30-34Fish
A. Characteristics1 Use gills for respiration or gas exchange2 Integumentary System consists of scales and mucus3 Appendages are paired fins for movement4 Ectothermic- animals that rely on the environment to warm their blood in their
bodies5 Lateral line- sense that allows fish to detect changes in the environment, water
temperature, and vibrations of food and other fish.6 Closed Circulatory System with a heart pumping blood through vessels7 Swim bladder- internal organ that adjust buoyancy.8 Most exhibit external fertilization- eggs fertilized outside of the mother
a. Breeding is called spawningb. Females lay spawns in the waterc. Males deposit sperm on them
B. Classes of fish1. Jawless Fish (Agnatha)- oldest and most primitive
a. Don’t have a well defined headb. Lack vertebrae and keep notochord as adultsc. Ex: Lamprey
2. Cartilaginous Fish (Chondrichthyes)a. Have skeletons of Cartilageb. Ex: Sharksc. Most Sharks are predators- hunters
a. Exception- Whale Sharksd. Rays that flat bodies and poisonous spines
3. Bony Fish (Osteichthyes)a. Have 3 body sections:
a. Headb. Bodyc. Trunk
b. Sensitive to smellc. Most bony fish are ray-finned
a. Ex: lungfishes, coelacanth
d. Bony fish have a 3 or 4 chambered heart
Chapters 30-34
AmphibiansA. Characteristics
1. Vertebrates2. live in water as larvae and on land as adults3. Breathes with lungs as adults and gills as larvae4. Moist skin with mucus glands5. Lacks scales and claws
B. No “typical type of species” so we will look at structures found in frogs1. Feeding and digestion
a. As larval tadpoles, they are herbivores/ filter feedersb. As adult frogs they are meat eatersc. As the frog develops into an adult the digestive track gets bigger
2. Respirationa. Gills and skin of larvab. Lungs- in adult
3. Circulationa. Heart is 3 chamberedb. Circulation is 2 loops
4. Excretiona. The urines routeb. Goes through the Blood- then to the Kidney- then to the uretur- the
urinary bladder- cloaca- then out of the body5. Reproduction
a. External reproduction1. the sperm fertilize the eggs outside of the female.
b. Male’s thumb stimulates the eggs to be resealed from thefemale.
6. Nervous system is well developeda. Nictitating membrane keeps eyes moist and protectedb. Tympanic membranes are eardrums
7. Integument- skin is smooth and moist8. Ectothermic- can not generate their own body heat
C. Undergo metamorphosis1. Aquatic larval stage to terrestrial adults
a. Ex: tadpole to a frog 2. Examples: Salamanders, Frogs and Toads, and Caecilians
Chapter 30-34 Reptiles
o Reptiles were the 1st vertebrates to live their entire life on land.o Characteristics:
o Vertebrates
o Dry, Scaly skin that protects from water loss.o Have lungs for gas exchangeo Terrestrial eggs- laid on land
Covered eggs- with shellso Ectothermic- can not generate there own body heato Carnivores and herbivoreso 3 chambered heart and 2 loop circulationo Presence of a cloaca
Excretory, digestive, reproduction functionso Developed organs of sense an vibration (snakes)o Reproduction is by internal fertilization
Oviparous- lay eggs that develop outside of the female.o Ex: Turtleo Ovoviviparous- young are born alive after they hatch from an
egg inside the female.o Ex: snake, lizard
Viviparous- bear their young aliveo Ex: mammals
Chapter 30-34Mammals
o Mammals are the most advanced and complex group of animalso Characteristics:
o Have hair or fur on their bodieso Endothermic- they generate there own body heat
Hair, high metabolism, sweat glands, and fat control the body temperature
o Most are viviparous- bear young alive and care for themo Young are fed milk from the mother’s mammary glandso Use lungs to breatheo Highly developed brainso Young are cared for by their parents until they are capable of
living on their owno Communicate by:
Sound, touch, visual displays, and odorso Orders of mammals:
Monotremes- lay eggs Oviparous- lay eggs that develop inside the mother. Ex: platypus, anteaters
Marsupials- young are born before development is complete and crawl into the mother’s pouch where they feed on milk until fully grown.
Ex: Kangaroos, Koalas, and the one in North America is the possum
Placental- young develop fully in the mother’s body and young are born alive.
o Have a 4 chambered heart
The Human SystemsChapter 35
The 11 Systems of the Body
o The Muscular System Structures
Skeletal muscle Smooth muscle Cardiac muscle
Function Produce voluntary movement Circulates blood through the digestive system
o The Nervous System Structures
Brain Spinal Cord Peripheral nerves
Function Recognizes and coordinates the body’s response to changes in
its internal and external environment.o The Respiratory System
Structures Nose Pharynx Larynx Trachea Brochi Broncholes Lungs
Function Gas Exchange
o The Integumentary System Structures
Skin Hair Swat Glands Oil Glands
Functions Serves as a barrier against infection and injury Helps regulate body temperature Protects the body from radiation
o The Digestive System Structures
Mouth Pharynx Esophogus Stomach Small and large intestines
Functions Converts food into simpler molecules
o The Excretory System Structures
Skin Lungs Kidneys Urethra Urinary Bladder Urethra
Function Eliminates waste products from the body
o The Skeletal System Structures
Bones Cartilage Ligaments Tendons
Functions Supports the body and protects the organs Allows movement Stores mineral reserves Provides a site for blood cell formation
o The Circulatory System Structures
Heart Blood Vessels Blood
Functions Bring Oxygen, nutrients, and hormones to cells Fights infection Removes cell waste Helps Regulate body temperature
o The Endocrine System Structures
Hypothalamus Pituitary Thyroid Parathyroid Adrenals Pancreas Ovaries (female) Testes (male)
Functions Controls growth, development, and metabolism Maintains homeostasis
o The Reproductive System Structures
Male Testes Epididymis Vas deferens Urethra Penis
Female Ovaries Fallopian Tube Uterus Vagina
Functions Produces reproductive cells In females it nurtures the developing embryo
o The Lymphatic System Structures
White blood cells Thymus Spleen Lymph Nodes Lymph Vessels
Functions Helps protect the body from disease Collects fluid loss from blood vessels and turns the fluid into the
circulatory system
Chapter 36 the Muscle and Integumentary System
The Skeletal System:
Endoskeleton-internal skeleton
o Contains 206 bones Five Functions:
o Supports the bodyo Protects internal organso Provides for movemento Stores mineral reserveso Provides a site for blood cell formation
Bone Formationo Osteocytes- mature bone cellso In a young embryo, most of the skeleton is
cartilageo Cartilage hardens into bone by the addition of
Osteocytes and mineralso This process is called Ossificationo Some Cartilage does not change to boneo The bone growth occurs in the ends of the
long bones, and in the mandible Bone Structure
o Bones Contain Osteocytes, minerals, blood vessels, and nerves
o Periosteum- tough layer of connective tissue on the outside of the bone
o Compact Bone- the outer layer of connective tissue on the outside of the bone.
o Harversian Canals- Contain blood vessels and nerves channels in the bony layer that contain blood vessels that feed Osteocytes
o Spongy Bone- strong area of the boneo Marrow- filling inside of the bone; tissue in
the center where blood vessels are made in red marrow and in yellow marrow stores fat
Some Bones like the ankle, phalanges, and wrist do not contain marrow.
Two Parts on the Endoskeleton
o Axel Skeleton- Supports the central axis of the body
Ribs and Sternumo Appendicular Skeleton- the bones of the
arms and legs, a long with the bones of the pelvis and shoulder areas
Joints- A place where one bone attaches to anothero Tendons- are connective tissue that attaches
to the muscles to the boneo Ligaments- hold the bones together in a joint
and attach bone to bone.o Types of Joints:
Fixed Joints- allow no movement. They are inter locked and held together with connective tissue
Ex: Places where bones and the skull meet. (Sutures)
Semi-movable joints- allow small amounts of movement
Ex: Joints between adjacent vertebrae
Freely Movable Joints- permit movement in one or more directions
Hinge joint- back and forth motion as in the elbow
Ball and socket joint- allows circular motion as in the shoulder and in the knee cap
Pivot Joint- one bone rotates around another as in the cranium on the atlas vertebra
Saddle Joint- bones slide against each other like wrist and ankle
Synovial Fluid- forms a thin film on the cartilage that covers the bony surfaces that form the joint
Bursa- reduces friction between the bones of a joint and also acts as a tiny shock absorber
Arthritis- the inflammation of the joints Sprain- injury to the ligaments by over
extending
The Muscular System:
Skeletal muscle (also called Voluntary Muscle)- has stripes called striationso These muscles are attached to bone to
move the bodyo Work in pairs
Flexor- bends the joint Extensor- strengthens the joint
o Smooth Muscle also called involuntary muscle
These are muscles you have no control over
Internal movement or contractions such as the digestive system
o Cardiac Muscle- only found in the heart combination of skeletal and smooth muscle
o Muscle Structure Each skeletal muscle is called a muscle
fiber (muscle fiber) Muscle fibers are made of the proteins
actin and myosino How muscles work:
Insertion- point where the muscle is attached to the moving bone by tendons
Origin- point where a muscle attaches to a stationary bone
During movement, the insertion moves toward the origin of a muscle
The Integumentary System:
Consists of hair, nails, and skin Has four functions:
o Protects against diseaseo Retain body fluido Regulates body temperature
Skin- is the largest organ in the bodyo Epidermis- the outer layer
Several Layers Outer layer is dead skin cells Cells contain a protein called keratin
that gives a rough texture and makes it water proof
o Dermis- inner layer of skin Composed of:
Collagen fibers Blood vessels Nerve endings Glands Sensory receptors Smooth muscles Hair follicles
The nerves present give the sensation of touch
Blood releases heat and helps maintain body temperature
Lymph helps fight disease A layer of fat below the dermis stores
food for energy and serves as insulation and protection for the body.
o Hairs are produced by cells at the base of the hair follicle- deep pockets in the skin
o Hair Shaft- extends beyond the skin and is made of keratin
o Oil glands- are in the skin and prevent the shaft from drying out
Nails- protect the ends of the fingers and toeso Form from- cells deep in the epidermiso Nails are made mostly of Keratin
Exocrine glands in the skin release secretions through tubes called ductso Sweat glands release- water, salts, urea,
and keratino Oil Glands secrete- sebum which softens
skin Melanin- controls the color of your skin and is a
pigmento Protects from UV radiation.
Biology Notes The Body Systems
Organizations of the Body
o Cell- Basic unit of lifeo Tissues- groups of cells that perform a single function
o Epithelial Tissue- cover the body surface (externally and internally)o Connective Tissue- connects body parts and provides support to the bodyo Nervous Tissue- transmits impulses throught the bodyo Muscle Tissue- provides movement by contracting and relaxing
o Organs- groups of different tissues that perform a single functiono Organ systems- groups of organs that perform a single closely related functiono The 11 organ systems work together to maintain homeostasis- stable internal conditions
The Nervous System
o The Nervous System- controls and coordinates functions throughout the body and responds to the internal and external environment
o Two parts of the Nervous System: Brain and Spinal Cordo Central Nervous System- relays messages, processes information, and analyzes
information Consists of the brain Brain and spinal cord are surrounded by: Bones
Bones- cranium and the vertebrae Cerebrospinal Fluid- acts as a shock absorber that protects the
Central Nervous System Three Meninges:
o Dura mater is the outer layero Cerebral Spinal Fluido Arachnoid layer is the middle elastic layero The inner third layer is the piameter
Brain- contains approximately 100 billion neurons Cerebrum- largest part of the brain: brain stem and the
cerebellumo On the top of the head- Anterioro Has two cerebral hemispheres (right and left side)o The outer layer is called the cerebral cortex and is folded
to maximize surface areao The Cortex is gray matter (no mycelin sheath)
The gray matter doesn’t regenerateo Beneath the cortex are the large masses of white matter
(has mycelin sheath) that connect the cortex to the rest of the body.
o This area controls: sight, hearing, and memoryo The Right side of the brain controls the left side and the left
side of the brain controls the right side because the nerve tracts leading from the cerebellum cross in the medulla, then lead into the spinal cord
o The medulla is interior to the cortex Cerebellum- is located at the back of the head dorsal under the
cerebrumo Controls balanceo Affected by alcohol
Brain Stem- connects the cerebrum to the spinal cordo Midbrain controls reflexeso Pons- relays messages between the Cerebrum and
Cerebellum and between the midbrain and the medulla.o Medulla oblongata- controls heart rate, breathing rates
Between the brain stem and the cerebrum is the Thalamus o Thalamus- directs sensory impulses to the craniumo Hypothalamus- works with pituitary gland to maintain
chemical balance in the body. Controls: hunger, thirst, sleep, anger, body temperature
Spinal Cord- nerve tissue extending from the medulla down into the spinal column
o Contains an outer sheath of white matter and an inner core of gray matter
Remember that white matter regenerates and gray matter doesn’t
o Spinal nerves ( 31 pairs)o PNS- Peripheral Nervous System
Consists of nerves that connect the CNS with the rest of the body Divided into two systems: Somatic, and Autonomic
Somatic NS controls voluntary movement Autonomic NS controls skeletal action like heartbeat, breathing,
ect The Autonomic NS is divided into two parts:
Sympathetic NS that controls organs during stress or high activity Parasympathetic NS which controls organs during routine
conditions These two systems are opposite each other. One is always a little
more in control that the other Reflex actions are involuntary and self protective movements Reflex arc is the action of the impulse going into the spinal cord and the
response coming from there. There is NO brain involved
NEURONS
o Neurons- cells that transmit impulses as electrical signalso Impulses- electrical signalso Parts of neuron:
Cell body- main part of the neuron containing the nucleus and the cytoplasm and fibers extending from it
Axon- carries impulses away from the cell body Dendrites- short fibers that carry impulses to the cell body
o An impulse travels from the dendrite to cell body to axon only. DCBAo In some neurons, the axon is surrounded by a membrane called the myelin sheatho Myelin Sheath- white stuff
o Some neurons lack a myelin and form gray that can’t regenerate.o Nerve Impulse- flow of electricity
o An impulse begins when a neuron is stimulated by another neuron or by the environment.
o The impulse travels from one neuron to the othero The impulse is carried by a chemical called a neurotransmitter across a space
called a synapse between the neurons
o Movement of the impulse: electrical- chemical- electrical Receptors- they are neurons that is carried by sensory neurons from the
receptors to the spinal cord and brain The Brain interprets the impulse and sends out a response The Response is carried by motor neurons to effectors
SENSE ORGANS
o Sense Organs- have receptors to pick up stimulio 5 different kinds of categories of sensory receptors
Pain Receptors- The chemicals released by damaged cells Thermo Receptors- Stimulated by temperature changes Mechano Receptors- detect touch/ pressure Chemo Receptors- smell; external Photo Receptors- sight, light, in our eyes
o Eye- for vision Iris- the colored part of your eye. It is a sphincter muscle Pupil- opening where the light goes in Lens- Bends the light to focus on the back of the eye called the retina Photoreceptors- light receptors
Rods- vision in dim light Cones- color light
Optic Nerve- carries impulses from retina to the cerebrum to be interpreted as vision.
The image on the retina is invertedo Ear- deals with hearing and balance
Vibrations enter the outer ear through the auditory canal From there, the hit the tympanic (eardrum) As the eardrum vibrates to a membrane it causes small bones: hammer,
anvil, stirrup to vibrate The Stirrup transfers vibrations to a membrane called the anvil window
that separates the middle ear and inner ear. Cochlea- small snail shaped tube that consists of fluid and lined with hair As fluid vibrates, impulses form and travel along the auditory nerve to the
brain Semicircular canals (3)
o Taste buds- found between bumps called papillae on the tongue and contain receptors for salty, sweet, bitter and sour.
o Olfactory glands- in the nasal passages and send an impulse to the brain from smell
o Skin- receptors for touch and deeper there are pain sensors.