2019 biological processes Flashcards
what plant hormones control leaf drop?
-auxin
-ethene
-(giberellins)
describe the processes that occur as a result of aldosterone secretion
- 3 na+ ions move into the blood and 2 potassium ions out of the blood at the collecting duct of the kidney
why is gibberellin classed as a plant hormone
-giberellin is a chemical messenger
-produced in one part of the plant but affects another
-affects activity of target cells/ tissues
-long lasting effects/ acts over a long period of time
-widespread effect
state the role of giberellin
-increase in stem length
-promotes fruit development
-seed germination
-hydrolysis of starch
what does benedicts not test for
non-reducing sugars
state the similarities with fish circulatory system and mammal circulatory system
-both are closed systems
-both have a heart
-both carry oxygen using haemoglobin
-both have arteries/ veins/ capillaries
state the features of a fish circulatory system
-single circulation- blood through heart once
-one atrium, one ventricle, no septum
-blood passes through two sets of caplillaries before returning to the heart
-blood pressure is lower
-less efficient a transporting oxygen
-fufills fishes needs as fish have a low oxygen demand
why is it possible that acetylchline can have an effect on the skin of a squid
-secereted into/ travels in blood
-binds to receptors on skins surface
-activates a G proten/ secondary messenger/ enzyme cascade
why are anabolic steroids effective when applied to the skin
-skin has a very large surface area for absorption
-skin has many networks of capillaries
-steroids are lipid soluble so can cross phospholipid bilayer
-muscles are close to skin so short diffusion pathway
what are some general issues with validity when evaluating a claim
-only a limited time/ short time was studied
-no detail providing method
-no detail of a control group
whats a conjugated protein
contain non protein groups
-iron ion
-prothetic group is attached by covalent bonds/ ionic interactions/ hydrogen bonds
why is a reduced heart rate seen in people who are aerobically fit
-they have an increased stroke volume
-they have an increased volume of ventricle
-increased thickness/ strength of muscle
why is the light inependent stage called the light indepenent stage
it doesnt require photons/ light energy
explain how selective breeding has led to increased yield in wheat
-breed high yielding wheat plants
-assess yeild
-cross breed selected/ high yielding offpsring
-over generations
-prevent self pollination/ prevent unwanted cross pollination
what can improve yield
-selective breeding
-use of fertiliser
-use of pesticide, fungicide, insecticide
-improved technology
