hormonal communicatiom/photosynthesis

describe how energy from light is harvested into different photosystems

• different pigments absorb different wavelengths of light

• accessory pigments pass energy from light into primary pigment chlorophyll a

• primary pigment becomes electrically excited and loses electrons to electron transport chain

• those become excited to a higher energy level

glycogenesis

production of glyocgen from glucose

gluconeogenesis

production of glucose by non carbohydrate sources

glycogenolyisis

production of glucose by breaking down glycogen

high glucose levels

• when glusose levels high in blood- detected by beta cells

• secrete insulin into blood

• target cells are hepatocytes on liver

• insulin binds to receptors on plasma membrane of hepatocytes

• adenyl cyclase activates cAMP

• more glucose channels open

• more glucose conveerted to fats and amino acids

• glucose converted to glycogen and level of blood glucose falls

when blood glucose is low

• detected by alpha cells

• glucagon secreted into blood stream by alpha cells

• target cells are hepatocytes

• more fatty acids used in respiration

• glycogenolysis

• gluconegenisis

• glucagon inhibits insulin secretion

• level of blood glucose rises

regulation of insulin secretion

• plasma membranes of beta cells contain calcium and potassium ion channels

• potassium ion channels are normally open while sodium ion channels are close

• potassium ions diffuse out of cell making inside more negative compared to outside

• when there is high glucose conc glucose enters cell

• glucose used in respiartion to make ATP high level of ATP causes potassium ion channels to close potassium can no loner diffuse out making it less negative

• calcium ion channels open calcium ions enter cell making vesicles containig insulin to fuse with membrane and release insulin through exocytosis