First Human Body Test Review Human Body Systems Reasons for 11 body systems in humans: 1. Allows for more complexity 2. More efficient 3. No overlap of functions 4. Less waste and energy use 5. Easy to maintain Homeostasis – the condition of a stable internal environment in an organism How the 11 systems depend on each other? Each systems provides a different, essential need for all the cells of the organism. 5 levels of organization in most living things 1- cell 2- tissue 3- organ 4- organ system 5- living organism Intro to Human Body Tissues Possible Essay -List the four basic types of tissues and state their distinct features and functions • Epithelial – sheets of tightly packed cells, always has a surface facing space, either outside or around internal space. EX: Forms many linings giving protection and containment on inside and outside of structures such as the skin, organs, and body cavities. • Connective – functions to bind and support other tissues. Cells in connective tissue are always surrounded by noncellular matrix, usually produced by those cells. Provides body structure as well as connects parts together allows people to move. EX: Found in skin, wraps fat cells, tendons, ligaments, cartilage bones • Muscle – Allow body, food, blood movement. Ex- Skeletal muscle, cardiac muscle and smooth muscle. • Nervous – Carry electrochemical messages called impulses to/from the brain which allow us to process, reflect, remember and understanding our environment. Ex. Neurons, rods, cones • Reproductive- Cells that go through meiosis and contain only one set of chromosomes and can be used to produce offspring. Ex: sperm and egg cells Integumentary System Possible Essay - List of the functions of the integumentary system (be able to describe as well) • Protection of interior parts from bacteria, chemicals, UV rays, and injuries. • Temperature regulation (sweat glands and goosebumps) • Sensory Reception (heat, pressure, pain, hot, cold) • Biochemical Synthesis (use sunlight, make vitamin D) Possible Essay - Describe the epidermis layer. Include the different types of cells and what they produce. • Made up of mostly dead epithelial cells. • Keratincytes produce keratin, which is the tough material in dead skin and also found in the basic structure of hair and nails. • Melanocytes produce melanin, which determines the color of skin and provides protection from UV rays. Describe the Dermis Layer, including its function Made up of living cells it also consists of: • Blood vessels • Nerve endings • Glands • Sense Organs • Smooth Muscle • Hair cells The function of the dermis layer is: control body temperature and sensory reception Name and describe the two glands found in the dermis • Sweat glands produces sweat when the body temperature rises. As water evaporates, it cools the air surrounding skin which makes it feel cooler. • Sebaceous glands produces an oil that keep the keratin-rich epidermis flexible and waterproof. The oil coats the shafts of hairs and surface of the skin to prevent water loss and also lubricates and soften the skin and hair. SKIN PROBLEMS Blisters rubbing causes the layers of epidermis or epid/dermis to separate and water fills in Burns 1st-degree - only epidermis, no blistering 2nd degree – blistering, deep layer epidermis damage 3rd degree – entire epidermis burned away Psoriasis – chronic, scaling of skin and inflammation of joints. Muscular/Skeletal Systems How many bones are in the human body? There are 206 bones in the human body. Possible Essay - Name and describe the four functions of bones • • • • “SSMB” Support – holds you up; protects heart, lungs, vertebrae, spinal cord Storage – help nerves and muscles function properly by storing minerals and stores fats Movement – allows human movement because muscle is attached to bones Blood cell formation – makes red and white blood cells What is the role of the osteoblast? Osteoblasts are living cells that deposit the minerals that make up the bones and the connective tissue holding the bones together. Possible Essay -Name and describe the four components of bones • Marrow – red marrow makes red and white blood cells and is found in the spongy bone of legs, arms, ribs, sternum and vertebrae. Yellow marrow stores fats. • Compact bone – located toward the ends of the long bones and provides most of the strength and support for bones such as the femur • Spongy bone – bone tissue with many open spaces, has stores minerals in it • Periosteum – tough living membrane covering a bone’s surface What is the function of cartilage and ligaments • Cartilage – provides a place for bones to continue growing, protects bone where two bones contact one another. • Ligaments – bands of tough tissue (connective tissue) that holds bones in place at and around joints. Name, describe and give an example of the five different types of joints • Ball and socket –Ball-shaped end of bone fits into a cup-shaped socket on the other bone allowing for widest range of motion including rotation, EX: shoulder and hip • Hinge joint –Allows movements in a single place, EX: elbows and knees • Pivot joint –Allows freedom of movement somewhat between ball and socket and hinge, EX: wrist, ankle, neck • Sliding joint –Bones moving into each other allowing sliding or twisting without any circular movement, EX: carpals in the wrist, tarcels in the ankle and vertebrae in the back • Fixed joints –Do not allow any movement and are extremely strong, EX: Joints of the skull BONE DISORDERS Osteoporosis – porous or weak bones that break easily Osteomyelitis – bacterial infection that can cause destruction of bones Arthritis – common joint problems cause by over 100 diseases How many muscles are in the human body? There are over 600 muscles in the human body Define the two groups of muscles. Give examples of each. • Voluntary muscles – conscious movement, facial expressions • Involuntary – blinking, moving food through digestive system, heart beating Name, describe and give an example of the three types of muscles • Cardiac – heart muscle • Smooth – in the digestive track wall, maintains movement of food • Skeletal – allow your bones/body to move What is the function of tendons? Attach muscles to bones by thick bands of connective tissue Possible Essay -Describe how muscles move joints, which in turn, moves the human. Muscle work in pairs. Tendons connect muscles to bones. One end of the muscle is attached to an origin bone, then the other end is attached by a tendon to the moving bone at the insertion point. When one muscle contracts, it shortens and pulls on the tendon which in turn pulls on the bone. This moves the bone. The opposing muscle relaxes/returns to normal length. Muscles work around joints, which are held together by ligaments. Cartilage cushions bones in joints. MUSCLE DISORDERS MUSCULAR DYSTROPHY – progressive weakness and degeneration of muscles controlling movement SPINAL MUSCULAR ATROPHY – genetic disease the affects voluntary muscles needed for crawling, walking, head and neck control, and swallowing Human Brain and Nervous System List the seven parts of the brain and briefly state their main function • Cerebrum – thinking part • Motor Area- part of the cerebrum that control vol. muscles • Cerebellum – controls balance, movement and coordination • Brain stem – controls all functions for body to stay alive (breathing, circulations, digestion) • Hippocampus – deals with memory • Pituitary gland – releases hormones in your body • Hypothalamus – brain’s inner thermometer List the different sensory organs and nerves in the human body (from labs) • • • • • • Eyes Ears Smell Taste Touch Heat Human Nervous System is divided into two regions: Central N.S. – the brain and spinal column Peripheral N.S. – made up of the neurons outside of the Central N.S Human have more that 1000 kinds of neurons, that fall into 3 general categories: Sensory neurons – recieve messages Interneurons – coordinate incoming and out going messages. Motor neurons – send messages to muscles Possible Essay -Describe how the parts of the nervous system work together when you touch something hot. Touch receptors send an electrical message to the brain alerting the brain that you are touching something hot. Before the brain receives the message, an interneuron intercepts the message as one of pain and responds by activating your motor neurons. The motor neurons stimulate your muscles to contract and pull away from the hot thing. Explain why tasks are easier to do if you practice them When you learn things, the message travels from one neuron to another. The brain eventually starts to create connections/pathways between the neurons. Well established pathways allow for messages to be sent more rapidly and thus carried out more quickly and easily. Define and state the function of the parts of the eye • Cornea – light rays are bent, reflected and focused, protects • Pupil – opening created by the iris • Iris – controls amount of light entering eye by regulating the size of the pupil • Lens – sharply focuses lights on to the retina • Vitreous fluid- focuses the image • Retina – captures light to pick up the image, has cone (color) and rods receptors • Choroid- shiny reflective back of eye • Optic Nerve- sends image to the brain • Sclera- outside membrane of eye • Blind Spot- point at which the optic nerve passes out of the retina since photo receptor cells are absent there Human Eye Describe why organisms have 2 eyes. • Three dimensional vision depend on viewing the same visual field with both eyes simultaneously. • This gives us depth perception Define and give the function of rods and cones • Rods –more light sensitive . Dim light vision depends entirely on rods • Cones – responsible for color vision Possible Essay - Describe how an eye functions when it sees an image Light rays are reflected from object to cornea. Iris controls the size of the pupil, which determines the amount of light entering the eye. Here the light rays are bent, refracted and focused by the cornea, lens and vitreous fluid. The lens sharply focuses and inverts the light rays on the light-sensitive retina on the back of the eyeball. The rods allow use to see in dim light and cones give better resolution and let us see color. The image is received upside down at the retina, and the light rays are converted to electrical impulses which are then transmitted through the optic nerve to the brain, which then flips the image over. Human Ear Explain how the ear plays a major role in maintaining one’s balance. The inner ear contains special hairs that act as gravity receptors. These hairs are found in the semi-circular canals. In humans, the inner ear is filled with fluid. As the head is rotated or the angle of the body changed, the fluid of the inner ear sloshes around, stimulating the gravity receptor hairs in the ear. When the hairs are stimulated, they send a message to the brain that relays information about balance. Possible Essay -Explain how the ear hears • Sound passes through the external auditory canal in the form of sound waves. • Sound vibrates the tympanic membrane (eardrum). • The vibrations are transmitted across the middle ear by three tiny bones, called hammer, anvil and stirrup. • Vibrations are passed from the stirrup to the inner ear through the oval window and then to the fluid in the cochlea. • Vibrations travel through the fluid, creating pressure which stimulates the mechanoreceptors located on the Corti. • Message is sent in the form of a nerve impulse through the cochlear nerve to the brain. Describe what causes hearing loss • Injury or irregularity in the structure of the ear • Ear wax build up • Bones in the middle ear may become fused after an infection • Prolonged high fever can lead to injury of the auditory nerves • Prolonged exposure to loud noise can cause the hairs in the cochlea to break