Anatomy Exam 1 Study Guide PDF
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This document provides a study guide for an anatomy exam, covering various biological topics. Topics include different types of chemical bonds, the structure and function of water, enzymatic reactions, organic molecules, ATP, and the dynamics of cell membranes. It details the concepts and mechanisms involved in these biological processes, aiming to aid in exam preparation.
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LECTURE 1 1. Describe ionic, covalent, and hydrogen bonds Ionic bonds: transfer of electrons, metal + nonmetal, NaCI, opposite charges attract, cations and anions Covalent bonds: sharing of electrons, nonpolar (equal sharing of e’s, H-H), polar (unequal sharing of e’s H2O) Hydrogen bonds: very wea...
LECTURE 1 1. Describe ionic, covalent, and hydrogen bonds Ionic bonds: transfer of electrons, metal + nonmetal, NaCI, opposite charges attract, cations and anions Covalent bonds: sharing of electrons, nonpolar (equal sharing of e’s, H-H), polar (unequal sharing of e’s H2O) Hydrogen bonds: very weak forces, multiple water molecules, partial positive H mixes with negative molecule (F,O,N) 2. Explain the structure of water and how it works as a solvent Water is a polar covalent molecule consisting of 2 hydrogen molecules and 1 oxygen. Oxygen will get an overall negative charge because it is more electronegative while hydrogen will get a positive charge. Due to its polarity (and H-bonds) it can dissolve many substances and is known as the universal solvent. 3. Explain the relationship between pH and the concentration of hydrogen ions in a solution, and relate this to the pH values of key body fluids The greater the concentration of H+ ions in a solution, the more acidic. The less the concentration of H+ ions in a solution, the more basic it is. Spinal fluid, blood, saliva and water have a general pH around 7 (meaning they are neutral). 4. Describe the process by which enzymes catalyze reactions Enzymes speed up the rate of chemical reactions without being consumed. They do this by lowering the activation energy required to start the reaction. Enzymes can be recycled and they bind to amino acids. LECTURE 2 1. Explain why carbon is the core of organic molecules Carbon has 6 protons, 6 neutrons and 6 electrons making it a very stable molecule. It can form long C-C bonds, which are the basis of organic molecules. Carbon can have single, double or triple bonds due to the structure of its outer shell. 2. Describe the basic structure of each of the four classes of organic molecules, and know where they are used in the body Lipids: fatty acids/triglycerides/phospholipids, they have a hydrophilic head and hydrophobic tail (forming the cell membrane), fats also play a role in sex hormones and signaling molecules Carbs: provide glucose and energy to the body, they are polar and hydrophilic, CH2O as basis Nucleic Acid: contain genetic instructions, DNA (double stranded) or RNA (single stranded), express and code for genes Proteins: amino acid building blocks, tissue repair, function as enzymes, receptors for communication and as antibodies for defense 3. Describe the structure of ATP and relate it to its ability to power chemical reactions in the body ATP is made of high energy bonds that can be broken (phosphorylation) to release energy. Adenine, a ribose sugar and three phosphate groups. Pumps molecules across cell membrane and provides energy for cellular activity. LECTURE 3 1. Describe the structure of the plasma membrane, including its lipid, protein, and carbohydrate components The plasma membrane is a phospholipid bilayer that regulates the entrance/exit of substances. It contains phospholipids, arranged so that the hydrophilic heads are pointing outwards and the hydrophobic heads and facing inward. To facilitate the entry of some molecules (glucose, charged ions), there are transmembrane proteins that are embedded. Cholesterol (a lipid) with help with membrane rigidity. Carbs (Glycocalyx) will help with cell recognition and interacting with extracellular material. 2. List the 6 major classes of membrane proteins and explain the role of each Transport proteins: serve as a channel/pump to move substances across membrane Anchor proteins: hold cell in place, attach membrane to cytoskeleton Receptor proteins: bind signals from other cells (triggers a response), hormones/neurotransmitters Cell-Cell Junction Proteins: allows nearby cells to bind with each other Membrane Enzymes: catalyze reactions at the cell membrane surface Recognition Proteins: identification, helps immune cell determine what agents are foreign and which are not 3. Explain how membrane is able to regulate transport of materials across the plasma membrane and to segregate compartments within the cell The cell membrane is selectively permeable, which regulates the transport and entrance of different materials into the cell. The membrane is flexible and able to move freely, giving proteins the ability to move as well. There is cytoplasm and cytoskeleton which helps with compartmentalization within the cell. 4. Define the terms isotonic, hypotonic, and hypertonic, and understand the consequences of placing cells into fluids of different tonicity Isotonic: equal concentration of solute and water in and out of the cell, balance/equilibrium (cell will not change shape) Hypotonic: low solute concentration outside the cell, water moves into the cell and cause bursting/lysis Hypertonic: more solutes outside the cell, water moves out of the cell, cell will shrink LECTURE 4 1. Describe the structure of the nucleus and the arrangements of DNA Membrane bound organelle in eukaryotes that contains genetic material. There is a nucleoplasm (which is fluid that surround the nucleus), nucleoli which are dark spots involved in ribosome synthesis. DNA is arranged in a double stranded helix, with 46 chromosomes at the time of cell division. Histone proteins help organize DNA 2. Describe the stages of synthesis of a protein and explain the role of each organelle Transcription: DNA to mRNA (messenger), takes place in nucleus, nucleus uses DNA as a template to produce RNA Translation: mRNA to protein, occurs at the ribosome, mRNA is used as a template to make a protein. 3. Describe the three types of protein modified and packaged into granules by the Golgi Apparatus Lysosomal - enzymes in the vesicle Proteins released by exocytosis from secretory vesicles Integral and peripheral proteins attached to the membrane 4. Name and describe the function of membranous and nonmembranous organelles Membranous organelles: mitochondria (powerhouse), nucleus (DNA storage), er, golgi (package proteins) Non Membrane: ribosomes (protein synthesis), centrioles, cytoskeleton (shape/structural support) LECTURE 5 1. Describe the role of stem cells in human tissues Stem cells are pluripotent meaning they have the ability to differentiate into many cell types. Found in early embryos. Cells can also be replaced via the division of stem cells which can help with wound healing and even spinal cord injuries. 2. Name the stages of the cell cycle and describe the events in each stage Interphase consists of 3 phases (g1,s and g2) G1= cell is growing, synthesizing proteins + RNA and replicating organelles (not the nucleus) S = DNA replication, each of the 46 chromosomes are duplication to form sister (twin chromatids), centrioles also duplicate G2= protein synthesis in preparation for mitosis Next is the mitotic phase (consisting of prophase, metaphase, anaphase and telophase) Prophase: chromatin forms into chromosomes (loose to tight DNA packing), sister chromatids join at centromere, mitotic spindle is assembled Metaphase: sister chromatids line up at the center of the mitotic spindle, chromosomes are aligned Anaphase: sister chromatids are pulled apart to opposite ends of the cell by microtubules Telophase: nuclear membrane forms around sister chromatids 3. Explain how the cell cycle is regulated and how this process is altered in cancer For regulation, the cell cycle has various checkpoints to make sure the cell is progressing in the right direction. Proto Oncogenes are genes that stimulate the cycle cycle if the environment is correct, however if these genes mutate they turn into oncogenes and cause abnormal and uncontrollable cell growth. 4. Describe metastasis This is the process by which cancer cells leave the original tumor and affect other areas of the body via the blood or lymphatic system. Essentially it is the spread of cancer beyond its original location. LECTURE 6 Define the term tissue and list the 4 tissue types in the body Tissue refers to a group of specialized cells that work together to perform a particular job. The 4 tissues types in the body include epithelial, connective, muscular and nervous tissue Define the term histology Histology is the microscopic study of tissue Explain the different kinds of cell-cell junctions and what advantages each provides to a group of cells Tight Junctions: super tight packing of cells, cells are fused together, molecules cannot pass through, act as a barrier and protect from external environment Gap Junctions: Cells are connected via membrane proteins and channels, allows cells to synchronize their activity Desmosomes: sort of like velcro, proteins hold together the cells together, not a complete barrier, provide strong adhesion Explain the transport processes of simple diffusion, facilitated diffusion, osmosis, primary active transport, secondary active transport, exocytosis and Endocytosis Passive transport (no ATP, high to low concentration) - Simple diffusion: lipid molecules moving directly through the bilayer, bilayer is hydrophobic so lipids can pass right through - Facilitated diffusion: movement of molecules via channel proteins - Osmosis: movement of water via aquaporins Primary Active Transport - Sodium/Potassium Pump: needs ATP, high to low concentration, sodium out and potassium in Secondary Active transport: no ATP involved, driven by concentration gradient, drives glucose against its gradient into the cell Exocytosis: the export of materials out of the cell Endocytosis: the import of materials into the cell (Both require ATP) Describe the 4 primary modes of cell-cell communication Direct: signaling via gap junctions, cell is releasing molecule directly into nearby cell Paracrine: chemical signal has to travel a short distance to get to neighboring cells, diffuse through the extracellular matrix Endocrine: slow acting, used for hormones, molecules released into the bloodstream and can travel long distances Synaptic: faster acting, neuron releases a neurotransmitter to the membrane of a target cell, impulse (quick) LECTURE 7 Describe the characteristics of epithelial sheets Tightly held together, little space between cells, avascular (no blood vessels), can be for absorption/protection, steady rate of cell division Name epithelial sheets by thickness and cell shape, and explain the advantages and disadvantages of the different arrangements Simple: one layer of cells (absorption) Stratified: more than one layer of cells (protection, more dense packing) Simple squamous: rapid diffusion due to 1 layer, not much protection Simple cuboidal: secretion and absorption, again not that much protection Simple columnar: absorption, digestive track, little more protection Stratified squamous: (always look at apical layer to identity), protection Wear and tear, outer skin, cell turnover, not great at absorption Explain the difference between endocrine and exocrine glands Endocrine glands release hormones into the bloodstream Exocrine glands release products into ducts, ducts, duct will carry product to a specific location Explain the main mechanisms by which gland cells release their secretions This can be either one of two ways, merocrine secretion or holocrine secretion. In merocrine secretion, the vesicle contents are released from the cell into a duct by wall of exocytosis. With holocrine secretion, the cell bursts and all cellular contents are released into a duct, causing the cell to die. Sebaceous glands and oil glands are holocrine (whole cell is replaced), while salivary and sweat glands are merocrine (product released into duct). LECTURE 8 1. Describe the common characteristics of all Connective Tissues and their roles in the body 2. Describe the types of cells, fibers, and ground substance comprising Connective Tissue Proper, and recognize the most common arrangements of CT Proper in the body All connective tissues have cells (primary type is the fibroblast), fibers and ground substance. Fibroblasts produce proteins that form fibers, help with wound/scar healing. There are three types of fiber in connective tissue including collagen fibers (strength), elastic fibers (stretch/recoil) and reticular fibers (very delicate, help organize space). Ground substance is a wet gel-like consistency that fills the gap between fibers and cells. Most common arrangements of CT proper include dense (tight packing) and loose (space for cell movement). Dense regular: fibers run in parallel, very strong collagen fibers, used for attachments like tendons (muscle to bone) and ligaments (bone to bone). Dense irregular: fibers run in all directions, joint capsules Dense elastic: elastic fibers, helps with recoil after stretching (lungs/heart) Loose areolar: storage of fat and fluid Loose adipose: source of padding and insulation 3. Describe the types of cells, fibers, and ground substance comprising Cartilage and recognize the most common forms of Cartilage in the body Cartilage is composed of chondrocytes and surrounded by perichondrium. Fibers include elastic (which aids in flexibility and recoil) hyaline (most common, loose packing) and fibrocartilage (dense fibers, pubic symphysis). Ground substance is a firm gel containing chondroitin sulfate. 4. Explain why some kinds of connective tissues can repair throughout life while others have limited ability to repair. Some kinds of connective tissue have easy access to blood and therefore nutrients (vascular), others (cartilage) is avascular and will thus will take a lot longer to heal. Bone being vascular will also have a much easier time repairing damaged/hurt tissue. LECTURE 9 Describe the roles of bone in the body Bones help with protection/support, movement, storage of minerals (especially calcium) and blood cell production. The surface of bones are covered by the periosteum. 2. Describe the types of cells, fibers, and ground substance comprising bone There are three main types of bone cells: osteocytes (inactive mature bone cells), osteoblasts (building new bone/bone deposition), and osteoclasts (tear down bone/bone resorption). Bones mainly have a collagen (strong) fiber framework and they need to be able to support a lot of weight. Ground substance is solid hydroxyapatite (calcium phosphate) crystals). 3. Describe the structure of a long bone, and compact and spongy bone arrangements within the bone A long bone consists of a diaphysis (long shaft) and two ends (epiphysis). The entire bone is surrounded by periosteum with the exception of the epiphyses which are covered by articular cartilage. A long bone is well vascularized (can heal well) and contains a marrow cavity with blood vessels and nerves. The outside of a long bone will be a compact bone (very dense structure, basic unit is the osteon). The inside of the bone will be spongy (porous, holes, made of trabeculae. 4. Describe the processes by which bone is formed through endochondral ossification, intramembranous ossification, and appositional growth, and how it repairs after injury Long bones grow in length through a process known as endochondral ossification, where cartilage is replaced by bone. Bones will form and take the place of the original hyaline cartilage. Intramembranous ossification refers to the process that forms flat bones (such as the skull), as the bones develop directly from mesenchymal (stem) cells. Appositional growth refers to the thickening/widening of bones in which a new bone matrix is formed. This is the process used for the development of most adult bones. Bone repairs itself following an injury by first forming a cartilaginous soft callus, which will later ossify and harden into bone. LECTURE 10 Define the term joint and explain the relationship between joint structure and degree of mobility A joint refers to the place where two bones meet (they articulate). There are three types of joint tissues including fibrous (like the skull), which are very stable but immobile. Cartilaginous joints are held together by cartilage (ribs) and synovial joints are connective tissue held around the joint (knee/shoulder). Synovial joints are highly mobile, but very unstable and are most prone to injury. Explain features that determine the shape and size of a bone Bones have different features and characteristics that aid in their overall function. If a bone is really thick in size, one can infer that is is primarily used to hold a lot of weight/weight bearing. Some bones can have depressions or openings depending on their function. Describe the organization of the axial skeleton and the body cavities it protects The axial skeleton serves to protect internal organs, provide attachment sites for limbs and provide support. This includes the skull, ribcage, vertebral column and hyoid bone (in neck). Describe the organization of the appendicular skeleton and explain the similarity in the pattern between the upper and lower limbs The appendicular skeleton connects the limbs to the axial skeleton and allows for range of movement. It includes the upper/lower limbs, and as well the pectoral and pelvic girdles. Both hands and wrist have small bones and phalanges.