BSC 181 1nd EditionExam # 1 Study Guide Lectures: 1 - 10Lecture 1 (January 14)Name The level of organization in order: Chemical level, Cellular level, A single Organ level, Organ system level (multiple organs working together), A complete OrganismWhat is Homeostasis? means maintain stable internal conditions even when changes occur in the environment. You can also think of it as a dynamic state of equilibrium. How is Homeostasis maintained? It is maintained when all of the organ systems work together. There is a continuous monitoring of the systems, and when there is a change in the body these systems are able to communicate that. The Nervous and Endocrine systems communicate changes through nerve impulses. These nerve impulses go to the control center of the body which the brain and spinal cord. When the brain and spinal cord receives these messages, the brain and spinal cord will then send signals back telling the body what it needs to do in order to regain homeostasis.How do nerve impulses function? There are receptors (sensors) in the body that monitor the environment and respond to stimuli. An example of a stimuli would be an increase in temperature. Once the receptors sense a stimuli, they send the signal to the control center which we know is the brain and spinal cord. The control center receives the input from the receptors and decides what effectors to put in place. An Effector is a group of muscles or glands that actually carry out the work that makes the body go back to normal. An example of an effector would be the sweat glands that make you sweat to bring your temperature back down.What is Negative Feedback? This is a controlled response/regulation. It reduces or shuts off the original stimulus, and then makes changes in the body so that it works in the opposite direction the stimulus was pushing it. It’s like when your room is too hot. You take the thermostat (stimulus) and stop it from making the room any hotter. You then turn it to the cooler side to counteract the heat.What is Positive Feedback? This is when the body enhances the original stimulus so that the body’s response speeds up. Nothing about this response is controlled, it just turns into a chain reaction of responses. This occurs during childbirth, or during blood clotting. Think of it as an avalanche or waterfall, something small quickly turns into a big chain reaction.What is the Anatomical Position? The body is erect and the feet are slightly apart with the palmsof your hands facing forward thumbs pointing away from the body.What are the Orientation and Direction Terms?Superior: Toward the head or upper end to the bodyInferior: Toward the lower part of the bodyVentral (anterior): Toward the front side of the bodyDorsal (posterior): Toward the back side of the bodyMedial: Toward or at the midline of the bodyLateral: Away from the midline of the bodyIntermediate: Between a medial structure and a lateral structureProximal: Nearest a point of attachment (example of a point of attachment: where your arm connects to the trunk of your body) Distal: Away from a point of attachmentSuperficial (external): Toward or at the body’s surface (think toward the skin)Deep (internal): Away from the body’s surface Axial: Head, neck, trunkAppendicular: Everything that has been added on (example: arms and legs which are referred toas limbs)Lecture 2 (January 16) Name and describe the three body planes:Sagittal Plane: divides the body vertically into left and right sections. If the “cut” is directly down the middle and the body is equally divided it is called midsagittal. If it is not directly down the middle of the body, if the “cut” is more to the left or right, it is called parasagittal.Frontal Plane: divides the body into front (anterior) and back (posterior), vertically. Transverse Plane: divides the body horizontally into superior (upper) and inferior (lower) parts Name and describe the two types of Serosa:Parietal Serosa: is the membrane that surrounds the inner walls of the central body cavitiesVisceral Serosa: this membrane covers the organs in the cavity, and this is in contact withthe organs unlike the parietal serosaWhich body cavity are the parietal and visceral membranes apart of: the ventral body cavity Name and describe the two subdivisions of the Dorsal Body Cavity: The Cranial Cavity: is in the skull and it protects the brainThe Vertebral/Spinal Cavity: which is located in the vertebral column, keeps the spinal cord safe. Because the spinal cord and the brain are very closely linked, the cranial and spinal cavities are continuous with one another.Name and describe the subdivisions of the Ventral body cavity: The Thoracic Cavity: is surrounded by the ribs and the muscles of the chestThe Pleural Cavities: Each one envelopes a lung, and they also envelop the medial mediastinum. The mediastinum holds the thymus gland, thoracic organs and also the Pericardial Cavity which is the other subdivision of the thoracic cavity.The Pericardial Cavity: this cavity envelops the heartThe Abdominopelvic Cavity: contains the Abdominal Cavity and the Pelvic Cavity. The abdominal and pelvic cavity is separated by the diaphragmThe Abdominal Cavity: is superior (above) to the pelvic cavity, and contains the digestive organsThe Pelvic Cavity: is the inferior (below) to the abdominal cavity, and contains theurinary bladder, some reproductive organs, and the rectumLecture 3 (January 19)Name and describe the two different models of the atom: There are a few different models that depict the atom. There is the Planetary Model, and the Orbital Model. We still look at and use the planetary model, but only for illustrations. It is an outdated model in terms of showing where the electrons are. You can never really tell where the electrons are in the atom only that they surround the nucleus. So the fact that the planetary model shows the electrons in perfect circular trajectories is incorrect. Which leads to the orbital model which is a more modern model which depicts an electron cloud instead.What is a molecule? A Molecule: is two atoms that are bonded together, the two atoms can be of the same element or they can be two atoms from different elements. For example, H2 (sameelement), or C2H4O2 (different elements)What is a compound? A Compound: is two or more of the different types of atoms bonded together. For example, C2H4O2What are the three different types of Mixtures? Solutions: These are homogeneous mixtures,