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BIO242 Final Exam 170 questions
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the following are basic cell functions of all cells except generating electrical impulses in order to relay information to other cells what is the proper progression of the levels of organization of the body? chemicals, cells, tissues, organs, body systems, whole body epithelial tissue has the following functions
- it lines the lumen (cavity) of organs that interact with material from the outside environment
- it provides a protective barrier
- it lines endocrine and exocrine glands --> NOT, it contracts to allow movement a homeostatic charge that is initiated outside of a target organ is considered extrinsic
skeletal muscles act as effectors a homeostatic response
- increase production of red blood cells in response to donating blood
- makes you shiver when exposed to a sudden chill.
- makes you sweat when exercising in the hot sun. ANSWER: all of the above. the following are all elements of the cell cytoplasm
- mitochondria
- centrioles.
- peroxisomes
- NOT CHROMOSOMES in the nova video shown in class, scientists discovered interference RNA (RNAi) when the addition of an extra purple pigment gene into a petunia produced white flowers (no purple pigment) what is the function of messenger RNA (mRNA)?
the final sorting and packaging of protein products destined for secretion into the extracellular space is facilitated by what organelle the golgi complex sorting signals on protein products cause secretory proteins to aggregate at the golgi membrane. coatomer proteins bind to the surface of the membrane and it starts to bow outwards (#1) secretory vessicle formation v-snares on the outside of the secretory vesicle bind to t-snares on the plasma membrane. this step results in the fusing of vesicle and plasma membrane, which is called exocytosis (#4) docking at plasma membrane lysosomes and peroxisomes both degrade unwanted or dangerous materials: lysosomes have hydrolytic enzymes that break down materials by the addition of a water molecule. the process of the cell "drinking" extracellular fluid is called pinocytosis
the binding of target molecules to specific receptor proteins on the outer surface of the plasma membrane followed by endocytosis is defined as receptor-mediated endocytosis pseudopods connect to form a phagosome phagocytosis dynamin pinches neck of vessicle pinocytosis clathrin causes plasma membrane to bow inward and connects to form a vessicle receptor-mediated endocytosis the elements of the cytoskeleton include
- microtubules
- microfilaments
- intermediate filaments ANSWER: all of the above
observe what dynein arms are the statements below regarding microfilaments are all true EXCEPT
- microfilaments are made of actin subunits
- microfilaments are hollow (NOT TRUE)
- microfilaments form a contractile ring in order to split duplicate cells during cytokinesis
- microfilaments form the mechanical stiffeners in microvilli. the main intermediate filament protein in skin and hair is called keratin (true/false) the plasma membrane is made only of a phospholipid bilayer false, the plasma membrane is predominantly made out of phospholipids, but includes many proteins, cholesterol, and associated carbohydrates. the small amount of carbohydrate associated with the outer surface of the plasma membrane has the following function it serves as a self-identity marker that allows for cell recognition.
what protein is considered a membrane protein?
- leak channels
- dock-marker acceptor proteins 3.carrier proteins 4.voltage gated channels
- all of the above (THIS ONE) the strongest adhesion of cells formed by cytoplasmic plaques, cadherin, and keratin proteins desmosome connexon tunnels allow the passage of small molecules between connected cells. gap junction claudin proteins create "kiss" sites and prevent the passage of fluid in between cells tight junctions the plasma membrane is considered semipermeable
when oxygen gets converted to carbon dioxide during cellular respiration, the carbon dioxide molecule has undergone oxidation in the first step of the citric acid cycle, what molecules combine to form the six carbon molecule citrate? acetyl-CoA an Oxaloacetate `what does the term chemiosmosis refer to the movement of ATP synthase powered by the flow of H+ ions along their concentration gradient resulting in ATP production the electron transport system steps
- NADH and FADH2 are oxidized and the electrons and protons released pass to complex I and complex II
- electrons release energy as they fall from a high energy state to a low energy state while passing between the electron transport system proteins
- free energy from the electrons allows for the transport of hydrogen ions across the inner mitochondrial membrane and into the intermembrane space
- oxygen accepts the low energy electrons and binds with 4 hydrogen ions to form water.
what mitochondrial process is involved in both the electron transport system and apoptosis cytochrome C cardiac muscle cells have the following characteristics. they are striated, branched, and have a single nucleus select a true statement regarding myofibrils
- a single muscle fiber contains many myofibrils
- each myofibril consists of many thick and thin filaments organized into sarcomeres
- sarcomeres contained within myofibrils are important for muscle contraction
- all of the above (CORRECT ANSWER) pay attention to where sarcomere is, the h zone (where the thick filament is) and the a band (the length of the green thing) what cytoskeletal element makes up thick filaments myosin
the spread of an action potential leading to Ca2+ release into the muscle fiber and finally resulting in the formation of cross-bridges and shortening of the sarcomere is called Excitation-contraction coupling if ATP is unavailable when muscles are in the process of contracting (as is true when a person dies), what is the result myosin heads detach quickly from actin, resulting in rigid muscles (rigor mortis) motor proteins provide only excitation to muscle cells-resulting in contraction. Muscle relaxation is achieved by what mechanism? the SERCA pump retrieves calcium ions and the tropomyosin-troponin complex changes conformation rapid stimulation of a muscle fiber before the fiber is fully relaxed leading to a sustained maximal contraction is called tetanus all the following statements are true refarding motor units except one. select the incorrect answer below
- a single motor neuron stimulates multiple muscle fibers
- muscles with smaller motor units overall create less powerful, but finely controlled movements
- recruitment of multiple motor units results in a stronger contraction
- motor units can work in shifts to prevent fatigue during maximal contractions (THIS ANSWER IS FALSE) what is the source that quickly provides ATP in the first few seconds of a muscle contraction creatine phosphate fast glycolytic muscle fibershave the following characteristics fibers hold an abundance of glycogen skeletal muscle fibers have the following characteristics. they are striated, unbranched, multinucleate what structures connect individual myocardial cells to prevent sharing stress and conduct action potentials intercalated discs
diastole Most ventricular filling occurs during what period of the heart cycle? atrial and ventricular diastole the T wave if the ECG represents what portion of the cardiac cycle? ventricular repolarization a cardiac arrythmia that results in a heart rate that is too slow is called bradycardia (too fast is called tachycardia) the scarring of heart valves by a toxin produced by bacteria causes what type of childhood illness strep throat (scarlet fever) how does the sympathetic division of the ANS effect cardiac heart rate? decreases permeability of K+, resulting in a faster heart rate.
what is the mechanism of extrinsic control of cardiac stroke volume? the sympathetic division increases ventricular contraction coronary arterial disease involves what change(s) to the cardiovascular system? creation of "plaque" within arterial walls large elastic arteries act as a _____ reservoir in the cardiovascular system pressure the increased metabolic state of cells (like in exercising muscle) causes__________ within the adjacent arterioles to increase blood flow vasodilation what changes to baroreceptors within the aorta and carotid arteries detect? mean arterial pressure (MAP) under normal conditions of bulk flow within capillary beds, more fluid plasma is filtered than is reabsorbed. to prevent edema, where does the remaining fluid go? it is absorbed by initial lymphatic vessels
the following are functions of the respiratory system
- gas exchange
- regulation of blood pH
- allows for speech what is not a function of the respiratory system? excretion of sodium. which of the following cells are present in alveoli?
- macrophages
- type I cells
- type II cells
- All of the above (CORRECT ANSWER) what is the term for the collapse of a lung due to disease or trauma? pneumothorax what muscles are contracting during active respiration? abdominal muscles
why is the chronic obstructive pulmonary disease (COPD) emphysema different from other COPDs such as asthma? emphysema symptoms include collapse of alveolar walls and asthma does not gas exchange between the atmosphere, blood, and tissue cells is facilitated by what kind of gradient? partial pressure gradients within the medullary center, what respiratory actions do the ventral respiratory group (VRG) cells influence?
- Inspiration
- Expiration what factors influence the increase of ventilation within the medullary respiratory center? increase in hydrogen ion (H+) in the brain ECF the following are functions of the urinary system
- maintains fluid balance
