Page 252 - Biology_F5

Coordination and Irritability

Task 4.10 4.3 Hormonal coordination in mammals
Stand upright and rotate your body several Task 4.11
rounds (about 5 times). Stop and explain Search for information from the library
with reasons how you feel. and internet sources the information on
hormonal coordination in mammals.
Exercise 4.3 Prepare a brief report.
FOR ONLINE READING ONLY
1. Various stimuli can be communicated to Hormonal coordination in mammals is a
a mammalian body through receptors. function of the endocrine system, which is
What are the adaptive features that can composed of a series of glands known as
aid this function to be carried out by the endocrine glands. They are called endocrine
mammalian body? glands because they are ductless. The system
2. Criticise the idea that, “the eye is not at is called “endocrine” to distinguish it from
all working in the same principle with “exocrine” glands that use ducts to convey
a camera” their chemical agents to the target cells,
3. What adaptive features make the retina tissues or organs e.g. glands producing
enable us to read and write? digestive enzymes. These glands secrete
4. Support the statement that, “the features specific chemical fluids called hormones
of the membranous labyrinth in the directly into the blood stream. Due to this
mammalian ear are essential for hearing reason, the endocrine gland is surrounded
and body balance”. by numerous blood vessels. A hormone is a
5. We can refresh our minds in daily lives chemical messenger produced by a ductless
through music. How does the music get gland, transported by blood and it shows
into our minds for refreshment? its effects in a region away from the site of
6. Staggering and even falling is evident if production. Table 4.2 gives a list of some
the inner ear is not properly functioning. hormones, endocrine glands and where they
How does the semicircular canal ensure are produced (Figure 4.35), and the activity
that these events don’t occur? that they regulate.
Pituitary Suprarenal
Parotid Ovaries
(in female)
Prostate
Pineal

Parathyroid
Thyroid
Mammary
(in females)

Pancreas
Red bone marrow Liver
Testes
(males)
Figure 4.35: Location of endocrine glands in a cattle

Form Five Student’s Book
245