the substances act as antigens
an antigen-antibody reaction occurs on surface of cells
the cells release a substance called histamine
the histamine causes irritation, itching and may stimulate nasal discharge
Mohaissack answered the question on October 5, 2017 at 11:31
-
What are allergic reactions?
(Solved)
What are allergic reactions?
Date posted:
October 5, 2017
.
Answers (1)
-
State the precautions that must be taken before blood transfusion
(Solved)
State the precautions that must be taken before blood transfusion
Date posted:
October 5, 2017
.
Answers (1)
-
Under what conditions would blood transfusion be necessary in people?
(Solved)
Under what conditions would blood transfusion be necessary in people?
Date posted:
October 5, 2017
.
Answers (1)
-
What is the difference between rhesus positive and Rhesus negative blood samples?
(Solved)
What is the difference between rhesus positive and Rhesus negative blood samples?
Date posted:
October 5, 2017
.
Answers (1)
-
Explain the meaning of : (i)Universal donor (ii)Universal recipient
(Solved)
Explain the meaning of :
(i) Universal donor
(ii) Universal recipient
Date posted:
October 5, 2017
.
Answers (1)
-
Explain why blood fowing in blood vessels does not normally clot
(Solved)
Explain why blood ?owing in blood vessels does not normally clot
Date posted:
October 5, 2017
.
Answers (1)
-
State the role of blood clotting on wounds
(Solved)
State the role of blood clotting on wounds
Date posted:
October 5, 2017
.
Answers (1)
-
Name a protein, vitamin, an enzyme and a mineral element involved in blood clotting
(Solved)
Name a protein, vitamin, an enzyme and a mineral element involved in blood clotting
Date posted:
October 5, 2017
.
Answers (1)
-
Explain how oxygen and carbon Iv oxide are transported in the blood
(Solved)
Explain how oxygen and carbon Iv oxide are transported in the blood
Date posted:
October 5, 2017
.
Answers (1)
-
How does the heart increase blood flow to some parts of the body during exercise
(Solved)
How does the heart increase blood flow to some parts of the body during exercise
Date posted:
October 5, 2017
.
Answers (1)
-
State the functional differences between a red blood cells and a White blood cells
(Solved)
State the functional differences between a red blood cells and a White blood cells
Date posted:
October 5, 2017
.
Answers (1)
-
Describe how cervical lumbar on sacra vertebrae are suited to their function
(Solved)
Describe how cervical lumbar on sacra vertebrae are suited to their function
Date posted:
October 5, 2017
.
Answers (1)
-
State the Ways in which the red blood cells are adapted to their functions
(Solved)
State the Ways in which the red blood cells are adapted to their functions
Date posted:
October 4, 2017
.
Answers (1)
-
Describe how mammalian blood components carry out their functions
(Solved)
Describe how mammalian blood components carry out their functions
a.Plasma
b.Red blood cells(Erythrocytes)
c. White blood cells(Leucocytes)
d. Blood platelets(Thrombocytes)
Date posted:
October 4, 2017
.
Answers (1)
-
State the functions of mammalian blood
(Solved)
State the functions of mammalian blood
Date posted:
October 4, 2017
.
Answers (1)
-
Give the reasons why pressure of blood is greater in the arteries than in the veins of mammals
(Solved)
Give the reasons why pressure of blood is greater in the arteries than in the veins of mammals.
Date posted:
October 4, 2017
.
Answers (1)
-
State the ways in which the composition of blood in the pulmonary arterioles differs from that in the pulmonary venules
(Solved)
State the ways in which the composition of blood in the pulmonary arterioles differs from that in the pulmonary venules
Date posted:
October 4, 2017
.
Answers (1)
-
Describe the structure and functions of the blood vessels
(Solved)
Describe the structure and functions of the blood vessels
i. Arteries
ii. Cappilaries
iii. Veins
Date posted:
October 4, 2017
.
Answers (1)
-
Explain why blood leaving the lungs may not be fully oxygenated
(Solved)
Explain why blood leaving the lungs may not be fully oxygenated
Date posted:
October 4, 2017
.
Answers (1)
-
Explain how the mammalian heart is adapted to performing its functions
(Solved)
Explain how the mammalian heart is adapted to performing its functions
Date posted:
October 4, 2017
.
Answers (1)