Physiology exam 1

Cells are

The basic structural and functional units of life that make up all living organisms.

Whats an example of of an organism classifed as a prokaryote

bacteria or archaea

Whats an example of an organism classifeid as a eukaryote

Animals, plants, fungi, or protists.

Heirachy of the multicellular organization

cells-tissues-organs-organ systems- organisms

What are the functions of cells

Protein Synthesis
Maintain Homeostasis, keeping us at steady state from external changes
Metabolic Activities, such as production and utilization of ATP

What’s an example of cell specialization?

Muscle cells are specialized to contract

Pancreatic Beta Cells are specialized to produce and secrete insulin

What is differentiation as it pertains to cells

Sequential developmental process that leads to specialization

What are two alternative terms for cell membrane

Plasma Membrane

Plasmalemma

What are functions of cell membranes

Forms boundaries between cells, cellular organelles, and their enviroments

Regulates movement of materials coming in and out of cells and cellular organelles

Is semi-permeable

Define semi-permeable

certain substances can pass through but not others

What are the 3 major components of cell membranes

Lipids, Carbs, Proteins

What the four main types of membrane lipids

Phospholipids, sphingolipids, glycolipids, and sterols

What is the main difference between glycerophospholipids and sphingolipids

Glycerophospholipids contain glycerol, Sphingolipids contain sphingosine instead of glycerol

What are two glycerophospholipids, and which leaflet would they most likely occur in?

Phosphatidylcholine: Outer Leaflet
Phosphatidylserine: Inner Leaflet
Phosphatidylethanolamine: Inner Leaflet

What are two sphingolipids?

Sphingomyelin
Ceramide
Gangliosides

what’s the difference between saturated and unsaturated fatty acids

Saturated fatty acids have singe bonds in their hydrocarbon chain, whereas unsaturated fatty acids have double bonds

What factors besides the degree of saturation affect melting temperatures of fatty acids

Length of hydrocarbon chain (longer), number of carbon atoms, tighter packing
Shorter chain=looser packing=lower melting point
Double bonds

What are two lipid alterations that a plant could perform to maintain normal membrane fluidity in a very hot enviroment?

increase the number of fatty acids and cholesterol, and decrease the number of unsaturated fatty acids

what is peripheral protein

A protein attached to the surface of a membrane, but still associates with the membrane

What is an integral protein

A membrane that’s imbedded into the membrane

what is a transmembrane protein

a membrane that extends all the way through the phospholipid bilayer and forms and ion channel

what are the roles of membrane protein

structural support, communication, adhesion, transport, cell-cell recognition, enzymes

What are two types of membrane carbohydrates?

glycolipids and glycoproteins, and are associated in the outer leafle

What is the glycocalyx?

The glycocalyx is all the carbohydrates associated with glycolipids and glycoproteins on the surface of the cell. They arimoortant for cell-cell communication as well as cell-extracellular matrix interactions. In some tissues, like the brush border of the small intestine, you can find enzymes associated with the glycocalyx

What are the major differences between prokaryotic and eukaryotic cells?

Eukaryotic cells have a distinct membrane bound nucleus and organelles and prokaryotic cells do not

What's the role of the nucleoid?

Where genetic information is located

What's the roll of ribosomes?

Sites of protein synthesis

What's the role of the flagella?

Locomotion

30. What's the role of the plasma membrane?

Forms boundary and regulates movement of in and out of the cells

31. What's the role of the cell wall?

Added layer of protection to cell

32. What's the role of the pili?

Movement(locomotion) and/or attachment

33. What is cytosol?

Fluid portion of the cell. Contains water, ions and macromolecules

34. What is cytoplasm?

The cytosine plus the suspended organelles (not counting the nucleus). Basically, everything between the nucleus and cell membrane

35. What's the role of the Golgi apparatus?

Receives and modifies proteins from the ER. Concentrates, sorts, and packages protein for export

36. What's the role of mitochondrion?

Major site of cellular metabolism. Converts carbs and fats to energy

37. What's the role of the ER?

Puts finishing touches on proteins that will be shipped out of the cell. Also lipid and steroid hormone synthesis, calcium ion storage and detoxification

38. What's the difference between the nucleus, nucleolus, and nucleoid?

Nucleus- eukaryotic cells, surrounded by a membrane where DNA is found

Nucleolus- eukaryotic cells, no membrane, area inside of nucleus where ribosomes are produced

Nucleoid- prokaryotic cells, NO membrane, region where DNA is found

39. What's the structure of the Nucleus?

It's surrounded by a double membrane that forms the nuclear envelope. The perinuclear cistern a is the space between the membranes.

40. What's the function of Nuclear Pores?

Connects the interior of the nucleus with the rest of the cytoplasm. They act to control the movement of molecules in and out of the nucleus

41. Where are ribosomes found in cells?

In eukaryotic cells they can be floating in the cytosine free or bound to the ER as the rough ER

42. What and where are ribosomes made?

Made of protein and ribosomal RNA, Are made in the nucleolus

43. What are two components of the endomembrane system?

Endoplasmic Reticulum, Golgi Apparatus/complex

44. What are the two types of Endoplasmic Reticulum?

smooth and rough

45. What's the function of smooth ER?

Chemical modification of other molecules, Site of lipid and steroid hormone synthesis, Storage of calcium ions

46. What's the function of rough ER?

Has ribosomes

Proteins are synthesized directly into the cisternae (lumen) of the RER

Fate of the proteins

Finishing touches off proteins

47. What are the three compartments of the Golgi Apparatus?

cis, medial, and trans region

48. What's the function of the cis region?

closest to ER and nucleus, receives proteins from ER

49. What's the function of the medial region?

middle, modification of proteins

50. What's the function of the trans region?

closest to the plasma membrane and outside of the cell, prepares protein for transport, responsible for lysosome synthesis

51. Which organelles play a role in the production, modification, and transport (trafficking) of proteins?

Nucleus, ribosomes, ER, Golgi apparatus

52. Which organelle contains digestive enzymes?

lysosomes

53. What can happen if the enzymes are faulty?

Lysosomal storage diseases-substances can build up in cell and lead to diseases

54. Describe the endosymbiotic theory

Eukaryotes evolved from prokaryotic cells that entered a mutually beneficial relationship. Mitochondria were once stand alone prokaryotic cells

55. What are functions of the cytoskeleton

Supports cell and maintains shape, Cell movement, Positions organelles within cell, Acts as tracks for "motor proteins", Anchors cell in place

56. What are the 3 types of cytoskeletal fibers?

Microfilaments (smallest)

Intermediate Filaments

Microtubules (largest)

57. Microfilaments are made up of what protein?

Actin

58. What is the monomer unit called?

G-Actin (Globular)

59. What is the polymer called?

F-Actin (Filamentous)

60. How many strands is the microfilament made from?

2 intertwined strands

61. What are roles of Actin in the cell?

Cell contraction

Adds structure to plasma membrane and shape of cells

Regulation of cytosine

Cell movement

increases surface area

Plays role in cell division (cytokinesis), formation of chromatin, gene transcription

62. What are the 3 phases of Polymerization?:

Lag Phase, Polymerization Phase, Steady State Phase

63. Which end requires energy and in what form (ATP or GTP)?:

Plus End, AT

64. Which end does the strand grow?:

Plus end

65. How does F-actin microfilament length affect the consistency of the cytosol of a cell?:

Smaller= more liquid, Longer= firmer, less liquid

66. List the actin binding protein that make the cytosol firmer:

Spectrin

67. How does it make it firmer?:

Provides cross linking between actin filaments

68. What's a cell that relies on Spectrin for its structure?:

Intestinal epithelial cells

69. What actin binding proteins makes cytosol less firm?:

Cofilin and Gelsolin

70. How does cofilin and gelsolin make the cytosol less firmer?:

Cofilin shortens filaments by twisting them until they break

Gelsolin shortens filaments by fragmentation (cutting) and needs calcium ions to do it

71. What is dystrophin and what class of disease/disorder is it associated with?:

A type of actin binding protein that links actin to the skeletal muscle cell membrane called the sarcolemma. Defects in dystrophin cause muscular dystrophy

72. What is the contractile protein associated with actin that plays an important role in both muscle cell physiology and cellular division?:

Myosin

73. What is the main role of intermediate filaments in the cell?:

Stabilize cell structure, Resist tension, Maintain position of nucleus and other organelles in the cell

74. type I and II intermediate filaments:

Associated with skin, hair and nails

Keratins

75. What is keratins?:

Derived from epithelial cells

76. Type III intermediate filaments:

structural support

Desmin, Vimentin, Glial fibrillary acid protein

77. What is Desmin?:

derived from muscle cells

78. What is vimentin?:

derived from fibroblasts, chondroblasts, and macrophages

79. What is Glial fibrillary acid protein (GFAP)?:

derived from glial cells in the nervous system

80. types IV and VI of intermediate filaments:

Structural support within neurons

Neurofilaments

81. What are neurofilaments?:

derived from neurons

82. Type V of Intermediate filaments?:

structural support within a cell nucleus

83. What's the assembly of intermediate filaments?:

Monomer-Dimer-Tetramer-8 tetramers-Intermediate filament

84. Is energy required for Intermediate Filaments?:

No

85. How many tetramer strands make up an intermediate filament?:

8

86. How many total monomer strands make up an intermediate filament?:

32

87. What's the most important function of microtubules?:

movement

88. Microtubules are made from what protein?:

tubulin

89. What are 3 important cell structures that are made from microtubules?:

Mitotic spindle, Cilia, and Flagella

90. What role do microtubules play in cell division?:

Movement of chromosomes during mitosis via the mitotic spindle

91. What role do microtubules play in the respiratory tract?:

Form the cilia that lines the tract - part of mucociliary escalator

92. What role do microtubules play in reproduction?:

Form the flagella of sperm and the cilia that line the fallopian tubes which assist in moving the egg towards the uterus

93. What's the assembly of a microtubule?:

Alpha + beta tubulin > tubulin heterodimer > protofilaments > 13 protofilaments = microtubule

94. Protofilaments are comprised of what?:

tubulin heterodimers (alpha and beta tubulin)

95. Is energy required to build the protofilaments?:

Yes, GTP

96. What two proteins are associated with microtubules?:

Dyneins and kinesins

97. What does Dyneins and Kinesins do?:

They use ATP to move cargo along the microtubules

Dynein moves toward the minus end, while Kinesins moves toward the plus end, facilitating intracellular transport

98. Is energy required for Dyneins and Kinesins?:

Yes, Atp

99. How are microfilaments and microtubules similar?:

Made of protein, Require energy, Have protein helper, Play roles in cell structure and motility

100. How are microfilaments and microtubules different?:

Microfilaments- smallest, use actin, ATP,

Protein helpers are- Spectrin, Cofilin, gelsolin, dystrophan

Microtubules-Largest, uses tubulin, GTP,

Protein helpers are- Dynein and Kinesins

101. What are the four main tissue types?:

epithelial, connective, muscle, nervous