Science Homework Help

QUESTION 1

1. Match each cell type with the correct description.

   –A.B.C.D. Chondrocyte –A.B.C.D. Osteocyte –A.B.C.D. Osteoblast –A.B.C.D. Osteoclast

   A. produces extra cellular matrix protein scaffold for bone B. When active, increases the extracellular calcium concentration in the ECF C. when active, decreases the concentration of calcium in the ECF D. mature bone cell

1 points

QUESTION 2

1. Which of the following statements about Helper T cells are true? Choose all of the correct answers.

   		Helper T Cells express TCRs.
   		Helper T cells express BCRs.
   		Helper T cells interact with antigens bound to Class I MHC molecules on other cells.
   		Helper T cells interact with antigens bount to Class II MHC molecules on other cells.
   		Activation of Helper T cells requires the membrane protein CD4.
   		Activation of Helper T cells requires the membrane protein CD8.

2 points

QUESTION 3

1. Swelling due to bulk flow from the plasma into the interstital fluid is the result of decreased protein permeability in the capillaries.

   True False

1 points

QUESTION 4

1. Are the following types of cells adaptive immune cells, innate immune cells or not immune cells?note: Although the two branches of the immune system interact with each other, cells are categorized as innate or adaptive by the types of microbial molecules they bind to.

   –A.B.C. Cytotoxic T cells –A.B.C. Neutrophils –A.B.C. Natural Killer Cells –A.B.C. Macrophages –A.B.C. Plasma cells –A.B.C. Mast cells –A.B.C. Helper T cells –A.B.C. Erythrocytes

   A. Adaptive B. Innate C. Not Immune Cells

3 points

QUESTION 5

1. Which of the following statements are correct? Choose all of the correct answers.

   		A decrease in the number of lymphoid stem cells could result in a decrease in red blood cell.
   		A person with an elevated level of platelets could experience easy bruising.
   		A person with a low number of white blood cells could have difficulty in fighting infections.
   		Platelets are more numerous than white blood cells, but contribute less volume to blood than white blood cells.

1 points

QUESTION 6

1. Match each immune cell with the method it uses to neutralize a pathogenic microbe that has infected a human

   –A.B.C.D.E.F. Cytotoxic T cell –A.B.C.D.E.F. Helper T cell –A.B.C.D.E.F. B cell –A.B.C.D.E.F. Natural Killer Cell –A.B.C.D.E.F. Macrophage –A.B.C.D.E.F. Mast Cell

   A. kills infected human cells after recognizing antigens displayed on MHC class 1 B. does not directly kill microbes; after recognition of a specific antigen displayed on MHC Class 2, it secretes molecules that help other cells to do so. C. phagocytoses microbes after recognizing specific antigens; secretes antibodies D. kills virus-infected human cells by releasing perforin and granzymes. E. Phagocytoses microbes after recognizing PAMPs; acts as an Antigen Presenting Cell to activate another type of immune cell F. Does not directly kill microbes; secretes histamine to initiate an inflammatory response.

3 points

QUESTION 7

1. Both inflammation and fever result in an increase in the temperature set point of the body.

   True False

1 points

QUESTION 8

1. Place the following events in activation of a B cell by a microbe in the order in which they would occur.

   –1.2.3.4.5.Several rounds of division occur, producing many B cells that all express the same B cell receptor. –1.2.3.4.5.A B cell differentiates from a lymphocyte stem cell, and the mature B cell expresses a specific type of B cell receptor on its cell membrane.–1.2.3.4.5.The B cell’s BCR (B cell receptor) binds to a foreign antigen with high specificity and high affinity.–1.2.3.4.5.Second messenger signaling is activated in the B cell.–1.2.3.4.5.Gene expression is altered in the B cell, and the B cell begins to divide.
   

2 points

QUESTION 9

1. Which of the following statements describe Class I MHC molecules, and which describe Class II MHC molecules?

   –A.B.C. This molecule is expressed on all nucleated cells. –A.B.C. This molecule interacts with proteins expressed on the surface of Cytotoxic T cells. –A.B.C. This molecule is expressed on the surface of Antigen presenting cells. –A.B.C. This molecule is important for activating Helper T cells –A.B.C. This molecule is expressed on the surface of B cells. –A.B.C. This molecule binds to antigens that come from primarily intracellular pathogens

   A. Class I MHC. B. Class II MHC C. Both Class I and Class II MHC.

2 points

QUESTION 10

1. Which of the following are phagocytic cells? Select the single best answer.

   		Macrophages
   		neutrophils
   		dendritic cells
   		All of the above.

2 points

QUESTION 11

1. Platelets can synthesize ATP via oxidative phosphorylation.

   		False
   		True

1 points

QUESTION 12

1. What type of B cell does not secrete many antibodies during a primary immune response, but is very important for a secondary immune response?

1 points

QUESTION 13

1. Which of the following topics do you find most challenging? You may select multiple topics.

   		Immune System Anatomy and Immune Cells
   		Innate Immune Cells
   		Complement and Interferon Function
   		B cell receptors/T cell receptors
   		B cell responses
   		Cytotoxic T cell responses
   		Helper T Cell responses
   		Interactions of antigens, BCR, TCR, MHC molecules and CD4/CD8
   		Immune Pathologies and HIV
   		Development of Bone and Blood cells

1 points

QUESTION 14

1. Which of the following is not a secondary immune tissue?

   		thymus
   		GALT
   		spleen
   		tonsils

1 points

QUESTION 15

1. If an individual failed to develop any mature lymphocytes, they would have lessened innate responses to infection and lessened adaptive responses to infection.

   True False

1 points

QUESTION 16

1. Place the following statements that describe the 5 steps in an adaptive immune response in the order in which they occur.

   –1.2.3.4.5.Long lived-immune cells allow the second response to a given microbe to be stronger and faster than the first response–1.2.3.4.5.Adaptive immune cells are born in the bone marrow, then mature in either the bone marrow or the thymus–1.2.3.4.5.Adaptive immune cells use specific receptor proteins to bind to antigens very specifically–1.2.3.4.5.Intracellular signaling pathways are initiated, causing the adaptive immune cell to change cell division, gene expression, and protein translation–1.2.3.4.5.Adaptive immune cells kill invading microbes, either directly or indirectly
   

2 points

QUESTION 17

1. Production of which of the following types of proteins during an innate immune response would directly lead to the lysis of invading bacterial cells?

   		Membrane attack complex
   		perforin
   		immunoglobulin
   		interferon

1 points

QUESTION 18

1. Which of the following statements about Cytotoxic T cells are true? Choose all of the correct answers.

   		Cytotoxic T Cells express TCRs.
   		Cytotoxic T cells express BCRs.
   		Cytotoxic T cells interact with antigens bound to Class I MHC molecules on other cells.
   		Cytotoxic T cells interact with antigens bount to Class II MHC molecules on other cells.
   		Activation of Cytoxic T cells requires the membrane protein CD4.
   		Activation of Cytotoxic T cells requires the membrane protein CD8.