F214 complete summary

I found this whilst looking for rescources and it has turned into being my main tool for revision i have changed somethings to better suit the teminology used in the text books, it is the complete syllabus then with a summary of each underneath it, have a look and download its so helpful also have f215

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Communication, Homeostasis & Energy
Communication and homeostasis
Communication

(a) Outline the need for communication systems within multicellular organisms, with reference to the need to
respond to changes in the internal and external environment and to coordinate the activities of different
organs.
Organisms need to respond to external stimuli, e.g. temperature,…

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Endotherms
Physiological (temp drops)
Peripheral skin thermoreceptors are stimulated by a decrease in external
temp
impulses are sent to the hypothalamus
vasoconstriction of arterioles to reduce heat loss by radiation / conduction /
convection
increased metabolic rate (respiration) to generate heat energy
release of adrenaline
shivering to generate heat energy…

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Nerves
(a) Outline the roles of sensory receptors in mammals in converting different forms of energy into nerve
impulses.
Light sensitive cells in the retina detect light intensity and range of wavelengths (colour).
Olfactory cells in the nasal cavity detect the presence of volatile chemicals.
Tastebuds detect the presence of…

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4. Voltage gated sodium ion channels open, and sodium ions flood in. As more sodium ions
enter, the membrane becomes positively changed on the inside compared to the outside.
5. The potential difference across the membrane reaches +40mV. The inside is positive
compared to the outside.
6. The sodium ion…

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The postsynaptic membrane contains:
· Specialised sodium ion channels that will only open when acetylcholine binds to
them









(j) Outline the role of neurotransmitters in the transmission of action potentials.
A neurotransmitter is a chemical that diffuses across the cleft of the synapse to transmit a
signal to the postsynaptic…

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· The creation of specific pathways in the nervous system is thought to be the basis
of conscious thought and memory.













Hormones

(a) Define the terms endocrine gland, exocrine gland, hormone and target tissue.
Endocrine gland
a gland that secrets hormones directly into the blood. Endocrine glands have no
ducts.…

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(d) Describe, with the aid of diagrams and photographs, the histology of the pancreas, and outline its role as an
endocrine and exocrine gland.
The exocrine cells of the pancreas secrete digestive enzymes into the pancreatic duct,
which transports them to the small intestine. These cells make up the majority…

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(f) Outline how insulin secretion is controlled, with reference to potassium channels and calcium channels in
beta cells.
1. The cell membranes of the cells contain Ca2+ and K+ ion channels.
2. The K ion channels are normally open, and the Ca ion channels are normally shut. K ions
diffuse…

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· Scientists have found stem cells in the pancreas of adult mice.
· Undifferentiated.

(i) Outline the hormonal and nervous mechanisms involved in the control of heart rate in humans.
Action potentials sent down the accelerator nerve to the heart from the cardiovascular
centre of the medulla oblongata to the…

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Nitrogenous wastes must be removed because the amino group is highly toxic, but proteins
and amino acids are very high in energy, so it would be wasteful to excrete them. In the
orthinine cycle, the amine group is removed to form ammonia, which forms urea, water and
a keto acid…

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