DAT Biology

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DAT Biology
2015-07-19 13:39:27

Flashcards related to the biology section of the DAT
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  1. Mechanisms of Digestion in the Mouth
    • Mechanical: mastication (chewing)
    • Chemical: salivary amylase (breaks down starches into maltose (glucose+glucose) 

    Food ultimately turns into bolus
  2. Mechanisms of Digestion in the Esophagus
    • Peristalsis: involuntary movement 
    • Made of up smooth muscle
    • At the end is the esophageal (cardiac) sphincter
  3. Mechanisms of Digestion in the Stomach
    • Mechanical: peristalsis (smooth muscle) and churning
    • Chemical: gastric glands secret HCl
    • Pepsinogen: zymogen and the conversion of pepsin occurs via the low pH
    • Pepsin: breaks down protein
  4. Mechanisms of Digestion in the Small Intestine
    • Food is now called chyme (very fluid)
    • Duodenum: pancreatic juices and bile acids are released (most digestion occurs here)
    • Contains zymogens trypsinogen and chymotrypsinogen and then enterokinase converts them into trypsin and chymotrypsin
    • Jejunum: involved in absorption of nutrients and contains microvilli to increase surface area
    • Ileum: involved in reabsorption of water and contains microvilli to increase surface area
  5. Mechanisms of Digestion in the Large Intestine
    • Absorbs water and salts out of fecal matter (that the small intestine didn't get)
    • Contains villi
    • Crypase: enzyme in LI that secrets liquid matter to make sure the fecal matter stays soft

    Contains microbiotia
  6. Mechanisms of Digestion in the Liver
    • Filter of the body: removes toxins
    • Stores glycogen 
    • Secrets bile salts: a cholesterol derivative that forms micelles which aids in breaking down fats
    • Site of fatty acid degradation via beta oxidation and gluconeogensis
  7. Gall Bladder
    Site of bile storage (bile salts) and pancreatic juices that are released in the small intestine
  8. Mechanisms of Digestion in the Pancreas
    • Produces: insulin (beta cells) and glucagon (alpha cells) (exocrine)
    • Contains: chymotrypsinogen, lipase, bicabonate (alkalis the acidic bolus and activates enterokinase), amylase and  trypsinogen
  9. Erythrocytes
    • Red blood cells: contains 4 subunits and hemoglobin each can bind 1 molecule of oxygen
    • lacks a nucleus and membrane bound organelles (anaerobic respiration)
    • formed in bone marrow 
    • erthropoietein: the hormone that is made in the kidneys and stimulates the formation of erythrocytes
  10. Leukocytes
    White blood cells
  11. Thrombocytes
    cell fragments aka platelets
  12. Plasma
    • non cellular component of blood (water, electrolytes, antibodies, albumen)
    • engages in CO2 and bicarb buffering
  13. Blood Types
    A, B, AB and O

    Rh+ (present on red blood cells) Rh- (not present on red blood cells)

    • AB+= universal recipient 
    • O- =universal donor
  14. Blood Type with antigens and antibodies
  15. Arteries
    • move blood AWAY from the heart
    • thick and muscular
    • carry oxygenated blood EXCEPT pulmonary artery
    • lack valves
  16. Veins
    • move blood TOWARD the heart
    • thinner than arteries and elastic
    • carry deoxygenated blood
    • contain valves to prevent back flow
  17. Capillaries
    • In tissues and involved in gas exchange
    • thin and unicellular
    • carry a mix of oxygenated and deoxygenated blood
    • lack valves
  18. Path of Blood in the Heart
    Deoxygenated blood comes from the lower and upper body into the inferior and superior vena cava (respectively)-->R atrium-->through tricuspid-->R ventricle-->through pulmonary semilunar valve -->pulmonary artery-->lungs-->pulmonary vein-->L atrium-->through bicuspid (mitral valve)--> L ventricle--> through aortic semilunar valve--> aorta--> to body (oxygenated)
  19. Flow of Electrical Conduction in Heart
    Starts in R atrium at SA (sinoatrial) node-->AV node in R ventricle (which delays it)--> bundle of hiss-->perkinje fibers (fast and causes contractions)
  20. Order of Air Passage

    (Please Leave The Breathing Alone)
    Pharynx, Larynx, Trachea, Bronchi, Bronchioles, Aveoli
  21. Tidal Volume
    Volume inhaled and exhaled during normal breathing
  22. Total Lung Capcity
    maximum volume of air the lungs can hold
  23. Vital capcity
    volume of air moved during a maximum inhalation followed by a maximum exhalation
  24. Expiratory reserve volume
    the volume left in the lungs at the end of a normal, resting exhalation
  25. Residual volume
    the air left after maximum exhalation (always air left in the lungs)
  26. Inspiratory reserve volume
    the volume that could be additionally inhaled at the end of a normal, resting inhalation
  27. Bone
    connective tissue made of concentric circles
  28. Osteoblasts
    build bone
  29. Osteoclasts
    break down bone

    when calcium is in need
  30. Cartilage
    flexible bone

    nose, ears, bronchi, kneecaps, ribs
  31. Tendon
    Connective tissues that hold muscle to bone
  32. Ligament
    connective tissue that holds bone to bone
  33. Skeletal Muscle
    Striated, contains many nuclei, and involved in voluntary contractions
  34. Smooth Muscle
    not striated, mono nucleated and is involved in involuntary contractions
  35. Cardiac Muscle
    striated, can be nucleated or not (depends on cell) and is involved in involuntary contractions
  36. Sarcomere (label)

  37. Which part of the sarcomere remains the the same?
    The A band!!!!
  38. Which part(s) of the sarcomere shrink during contraction?
    the H and I bands
  39. Dendrites
    Receive the signal via electrical stimulation and neurotransmitters
  40. Cell body (soma)
    transmits the signal
  41. Axon
    transfers the signal down the neuron
  42. Synaptic Terminals
    release the neurotransmitters into the synaptic gap to be received by other neurons
  43. Myelin
    From schwann cells and insulated the axon to promote "jumping" of electrical signal
  44. Relative refractory period
    a period of time after an action potential during which new action potentials are very difficult or impossible to initiate immediately
  45. Chrondrocytes
    Cells responsible for synthesizing cartilage
  46. Two subdivisions of the nervous system
    Central and Peripheral
  47. Central nervous system
    brain and spinal chord
  48. Two subdivisions of the peripheral nervous system
    somatic and autonomic
  49. Somatic
    skeletal muscle, the muscle that CAN be controlled
  50. Autonomic
    muscle that cannot be controlled (organs and reflexes)

    Sympathetic: "fight or flight" response (epinephrine and neorepinephrine)

    Parasympathetic: "rest and digest" response controlled by VAGUS nerve
  51. Endocrine glands
    synthesize and secrete chemical substances called hormones directly into the circulatory system
  52. Exocrine glands
    secrete substances transported by ducts 

    ex. Gall bladder
  53. Structures from Mesoderm
    muscles, kidneys, skeletal system, connective tissue, bone, cartilage, adipose tissue, circulatory system, lymphatic system, dermis, genitourinary system, serous membranes, and notochord.
  54. Structures from Ectoderm
    epidermis, hair, nails, lens of the eye, sebaceous glands, cornea, tooth enamel, the epithelium of the mouth and nose, intelligence, nervous system
  55. Structures from Endoderm
    the stomach, the colon, the liver, the pancreas, the urinary bladder, the epithelial parts of trachea, the lungs, the pharynx, the thyroid, the parathyroid, and the intestines (most internal organs), most endocrine function
  56. Morula
    solid ball of undifferentiated cells
  57. Blastula
    Hollow ball of cells 

    Blastocoel: fluid filled cavity
  58. Amnion
    Thin, tough membrane containing a watery fluid called amniotic fluid which serves as a shock absorber of external pressure
  59. Chorion
    membrane that completely surround the amnion and assists with transfer of nutrients from the mother to the fetus
  60. Allantois
    develops as an out pocketed of the gut

    the blood vessels of the allantoic wall enlarge and become the umbilical vessels which connect the fetus to the developing placenta
  61. Yolk sac
    site of early development of blood vessels, becomes associated with the umbilical vessels
  62. plasmid
    circular rings of DNA which contain accessory genes
  63. episomes
    plasmids capable of integration into the bacterial genome
  64. Mode of replication of bacteria
    binary fission (asexual)
  65. Transformation
    process to increase genetic variability in bacteria in which a foreign chromosome fragment (plasmid) is incorporated into the bacterial chromosome via recombination, creating new inheritable genetic combinations
  66. Conjugation
    process to increase genetic variability in bacteria by the transfer of genetic material between two bacteria that are temporarily joined 

    only bacteria contains plasmids called sex factors (F factor) can do this

    transferred from F+ male to F- female
  67. Transduction
    process to increase genetic variability in bacteria and occurs when fragments of bacterial chromosome become packaged into the viral progeny produced during such a viral infection

    the closer two genes on a chromosome the more likely they will be transduced together
  68. Recombination
    process to increase genetic variability in bacteria and occurs when linked genes are separated 

    occurs by the breakage and rearrangement of adjacent regions of DNA when organism carrying different genes or alleles for the same traits are crossed
  69. Inducible systems
    repressor binds to the operator, forming a barrier that prevents RNA polymerase from transcribing the structural genes and there for an inducer must bind to the repressor to inhibit it from stoping transcription
  70. Repressible system
    The repressor is inactive until it combines with a corepressor and once the repressor-corepressor complex has been formed the repressor can bind to the operator and prevent transcription
  71. Constitutive genes
    always on, incapable of being turned off

    (regulatory enzymes not coded for properly)
  72. Cell Theory
    • all living things are made up of cells
    • cells come only from pre-existing cells
    • cells are the basic functional unit of life
    • chemical reactions of life take place within the cell
    • cells carry genetic information in the form of DNA and this info is passed from parent to daughter cells
  73. Components of the cytoskeleton
    • microtubules (hollow rods polymerized by tubulin-->cilia and flagella)
    • intermediate filaments
    • microfilaments (actin-->muscle contraction)
  74. Symporters
    carrier molecules involved in active transport that transport two or more ions or molecules in the same direction across a membrane
  75. Antiporters
    carrier molecules involved in active transport that transport two or more ions or molecules in the opposite direction across a membrane 

    ex.) Na+/K+ ATPase
  76. Pinocytosis
    "cellular drinking"

    brings fluids or small particles from the extracellular material inside the cell
  77. Phagocytosis
    "cellular eating" 

    engulfing of large particles from the extracellular material
  78. Brownian movement
    kinetic energy spreads small suspended particles throughout the cytoplasm of the cell
  79. Cyclosis or streaming
    the circular motion of cytoplasm around the cell transports molecules
  80. endoplasmic reticulum (intracellular circulation)
    the ER forms a network of channels through the cytoplasm and provides a direct and continuous passageway from the plasma membrane to the nuclear membrane
  81. G1 of interphase
    • This phase initiates interphase
    • Active growth phase that can very in length
    • Cell increases in size and synthesizes proteins 

    The length of G1 determines the length of the entire cell cycle
  82. S in interphase
    period of DNA synthesis
  83. G2 of interphase
    the cell prepares to divide and it continues to grow and synthesize proteins
  84. M in interphase
    Last phase in the cell cycle and during this phase mitosis or meiosis occurs
  85. Mitosis
    Occurs in somatic cells and results in two identical daughter cells that contain a complete copy of the original genome (diploid cells)
  86. Prophase (mitosis)
    • chromosomes condense
    • centrioles migrate to opposite poles
    • spindle apparatus forms
    • nuclear membrane dissolves
  87. Metaphase (mitosis)
    • spindle apparatus attaches to each chromatid at its kinectocore
    • spindle fibers align the chromosomes at the center of the cell forming metaphase plate
  88. Anaphase (mitosis)
    • centromeres split giving each chromatid its own distinct centromere
    • the sister chromatids are pulled apart and toward opposite poles by the cell

    the START of cytokinesis!!!
  89. Telophase (mitosis)
    • spindle apparatus disappears
    • nuclear membrane forms around new chromosomes
    • chromosomes uncoil
  90. Cytokinesis
    • cytoplasm divides into two daughter cells with a complete nucleus and set of organelles 
    • in animals: cleavage furrow forms and cell membrane indents along the equator of the cell eventually separating the two nuclei
    • in plants: a cell plate forms between two nuclei, effectively splitting the plant cell in half and allowing the cell to divide
  91. chromatid
    one strand of the sister chromatid pair
  92. chromosome
    the condensed sister chromatid pair
  93. Meiosis
    • The process by which sex cells are produced 
    • involved duplicating its chromosome before undergoing the process 
    • produces haploid cells  (4 of them)
    • involved two divisions of primary sex cells,resulting in 4 haploid cells called GAMETES
  94. Interphase (meiosis)
    • similar to mitosis 
    • parent cell's chromosomes are replicated during interphase resulting in 2N sister chromatids
  95. Prophase 1 (meiosis)
    • chromatin condenses into chromosomes
    • spindle apparatus forms
    • nucleoli and nuclear membrane disappear
  96. Synapsis
    homologous chromosomes come together and intertwine
  97. homologous chromosome
    chromosomes that code for the same traits, one inherited from each parent
  98. Tetrad
    the term referring to a synaptic pair of homologous chromosomes

    (because at this stage chromosomes consist of two sister chromatids, each synaptic pair of HCs contains four chromatids)
  99. Crossing over
    • when the chromatids of HCs break at corresponding points and exchange equivalent pieces of DNA 
    • increases genetic variation

    Note: the two pairs of sister chromatids are no longer identical after recombination has occurred
  100. Chiasmata
    the points of contact between HCs where crossing over can occur
  101. Metaphase 1 (meiosis)
    Homologous pairs (tetrads) align in middle and each attaches to a separate spindle fiber at the kinectochore
  102. Anaphase 1 (meiosis)
    homologous pairs separate and are pulled to opposite sides of the cell
  103. Disjunction
    • each chromosome of paternal origin separates from its homologue of maternal origin and either chromosome can end up in the daughter cell
    • accounts for a fundamental Mendelian Law
    • distribution of homologous chromosomes to the two intermediate daughter cells is random with respect to parental origin 
    • each daughter cell has a unique pool of genes from a random mixture of mother and father origin
  104. Telophase 1 (meiosis)
    • nuclear membrane forms around each new nucleus 
    • each chromosome still consists of sister chromatids joined at the centromere
  105. Second meiotic division
    • very similar to mitosis except NOT preceded by chromosomal replication
    • chromosomes align at equator, separate and move to opposite poles and are surrounded by a reformed nuclear membrane
    • new cells are haploid 

    NOTE: in women only ONE of these four daughter cells becomes a function gamete; the other two or three cells are destroyed by the body
  106. Nondisjunction (kinda important)
    • Either the failure of HC to separate properly during meiosis 1 or the failure of sister chromatids to separate properly during meiosis 2
    • resulting zygote can have 3 copies of that chromosome (trisomy--somatic cells have 2N+1 chromosomes) 
    • resulting zygote can have 1 copy of that chromosome (monosomy--somatic cells will have 2N-1 chromosomes)

    Trisomy example: Down syndrome which is caused by trisomy of chromosome 21

    Most trisomies and monosomies are lethal and cause the embryo to spontaneously abort 

    Nondisjunction of sex chromosomes can occur and result in the individuals with extra or missing copies of X and Y chromosomes
  107. Chromosomal breakage

    breakage of the chromosome and this chromosome is said to have a deficiency 

    may occur spontaneously or be induced by environmental factors (mutagens and X-rays)
  108. Compact bone
    • dense bone with no cavities when observed with the naked eye
    • deposited in structural units called Haversian systems or osteons
  109. Spongey bone
    • less dense and consists of an interconnecting lattice of bony spicules
    • Yellow or red bone marrow

    • Yellow: inactive and infiltrated by adipose tissue
    • Red: involved in blood cell formation
  110. Endochondral ossification
    existing cartilage is replaced by bone

    Long bones arise primarily from this
  111. Intramembranous ossification
    embryonic or undifferentiated connective tissue is transformed into and replaced by bone
  112. Axial skeleton
    skill, vertebral column, rib cage
  113. Appendicular skeleton
    bones of limbs, pectoral and pelvic girdles
  114. Transverse tubules (T-system)
    • in skeletal muscle
    • provides a channel for ions to flow into the sarcomere and initiate an action potential
  115. Neuromuscular junction
    the link between the nerve terminal and the scarolemma of the muscle fiber
  116. Tropomyosin and Troponin C
    bind to actin in low calcium states and inhibit myosin from binding 

    when calcium is high the are alloesterically changed and myosin can bind to actin
  117. Role of ATP in muscle contractions
    required for myosin heads to release from actin filaments
  118. Role of Pi in muscle contractions
    released and causes the power stroke
  119. Cori Cycle
  120. Creatine Phosphate
    a high energy compound that serves a temporary energy store in vertebrates
  121. Myoglobin
    • Hb like protein found in muscle cells
    • has a high oxygen affinity and maintains the oxygen supply in muscles by tightly binding to oxygen
  122. The cause of the "lub dub" sound in the heart
    the successive closing of the atrioventricular and semilunar valves
  123. Systole
    period in which ventricles contract,forcing blood out of the heart
  124. Diastole
    period of cardiac muscle relaxation during which blood drains into all four chambers
  125. Cardiac output
    total volume of blood the left ventricle pumps out per minute 

    heart rate x stroke volume
  126. Hormone secreted by adrenal medulla that affects heart rate
    epinephrine (adrenaline)
  127. Function od the smallest lymphatic vessels (lacteals)
    collect fats in the form of chylomicrons from the villi in the small intestine and deliver them into the blood stream bypassing the liver
  128. Lymph nodes
    swellings along the lymph vessels containing phagocytic cells (lymphocytes) that filter the lymph and remove and destroy foreign particles and pathogens
  129. Plasma
    the liquid portion of the blood

    mixture of nutrients, salts, respiratory gases, wastes, hormones, and blood proteins (antibodies, albumin, fibrinogen)
  130. Thromboplastin
    converts the inactive plasma protein prothrombin (from the liver) into its active form thrombin

    with the help of vitamin K and calcium cofactors
  131. Thrombin
    converts fibrinogen into fibrin
  132. Fibrin
    clotting factor that coats the damaged area and traps blood cells to form a clot
  133. Collagen of damaged vessel (clotting)
    releases a chemical that causes neighboring platelets to adhere to one another and form a platelet plug
  134. The respiratory system (uncommon functions)
    continually moves oxygenated air over this area protecting respiratory surface from infection, dehydration, pH and temperature change
  135. Surfactant
    protein complex secreted by the cells in the lungs that prevents the cells from collapsing by decreasing surface tension of alveoli
  136. What happens when the CO2 and H ion levels are increased?
    The breathing rate increases
  137. What happens when the O2 blood levels change?
    Nothing significant on the respiratory center
  138. Path of O2 and CO2 in gas exchange

    • Oxygen diffuses from alveolar air into blood
    • Carbon dioxide diffuses from blood into the lungs