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AQA B1!!!!! Hi guys, if you are stuck on any questions for B1 or don't understand something please feel free to ask me. It will help for your understanding and my revision.
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(Original post by CosineOfPi)
neurones at least 4 marker
neurones at least 4 marker
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#5
(Original post by Nihaj)
A stimulus is detected by the receptor cells. The receptor sends an electrical impulse to the sensory neurone. This electrical impulse travels through the sensory neurone till it reaches the synapse. The electrical impulse can't travel across the synapse (A synapse is the junction between two neurones) so instead a chemical is released which travels across from the sensory neurone to the relay neurone (across the synapse). An electrical impulse is then passed from the relay to the motor neurone. The motor neurone sends this electrical signal to the effector (muscle) which causes the reflex.
A stimulus is detected by the receptor cells. The receptor sends an electrical impulse to the sensory neurone. This electrical impulse travels through the sensory neurone till it reaches the synapse. The electrical impulse can't travel across the synapse (A synapse is the junction between two neurones) so instead a chemical is released which travels across from the sensory neurone to the relay neurone (across the synapse). An electrical impulse is then passed from the relay to the motor neurone. The motor neurone sends this electrical signal to the effector (muscle) which causes the reflex.
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(Original post by mariyahx)
bacteria 6 mark question
bacteria 6 mark question
When an antibiotic is overused bacteria can mutate and produce new anti biotic resistant strains. So when the antibiotic is used all the non-resistant pathogens are killed but the resistant bacteria survive. The resistant bacteria reproduce and the population increases. Only new antibiotics will be able to kill the resistant bacteria. This could lead to an epidemic if new antibiotics aren't found quick enough.
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(Original post by CosineOfPi)
get in the "diffuse" classic AQA wanna hear it make a mnemonic for it SRSRME idk something like Simon Rides Silly Red Massive Elephants
get in the "diffuse" classic AQA wanna hear it make a mnemonic for it SRSRME idk something like Simon Rides Silly Red Massive Elephants
But i believe for 4 marks you won't have to mention much about the synapse. Depends on the question really.
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#9
(Original post by hafsa23)
Adult cell cloning please
Adult cell cloning please
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#10
(Original post by andew_451)
cloning isnt in edexcel biology one
cloning isnt in edexcel biology one
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#11
(Original post by Nihaj)
If you're talking about resistant bacteria:
When an antibiotic is overused bacteria can mutate and produce new anti biotic resistant strains. So when the antibiotic is used all the non-resistant pathogens are killed but the resistant bacteria survive. The resistant bacteria reproduce and the population increases. Only new antibiotics will be able to kill the resistant bacteria. This could lead to an epidemic if new antibiotics aren't found quick enough.
If you're talking about resistant bacteria:
When an antibiotic is overused bacteria can mutate and produce new anti biotic resistant strains. So when the antibiotic is used all the non-resistant pathogens are killed but the resistant bacteria survive. The resistant bacteria reproduce and the population increases. Only new antibiotics will be able to kill the resistant bacteria. This could lead to an epidemic if new antibiotics aren't found quick enough.
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(Original post by hafsa23)
Adult cell cloning please
Adult cell cloning please
So for this question lets take a cow for example
Firstly a body cell is taken from a cow. A egg cell is taken from a different cow. The nuclei from both cells are removed. The nucleus from the body cell is placed in the empty egg cell (because we removed the nucleus). Then the cell is shocked as it starts the cell division. The cell will divide and form an embryo which is then inserted into the womb of the surrogate mother.
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#14
(Original post by hafsa23)
Adult cell cloning please
Adult cell cloning please
1. Take a skin cell from the organism you want to clone...
2. Remove the Nucleus
3. Remove an unfertailised egg from an egg donor
4. Remove the eggs nucleus
5. Put the egg and the nucleus from the skin cell together and give an electric shock so they join
6. Give another electric shock to stimulate division into an embryo
7. Place the embryo into the surrogate mother's uterus
8. A clone of the organism you got the skin cell from will be born!
Hope this helps! x
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#15
Do you know if we have to learn all the indicator species and what they do? E.g. fresh water shrimp, mayfly larvae..
Do we need to know what they are affected by and stuff ?
Thank you
Do we need to know what they are affected by and stuff ?
Thank you
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#16
Adult cell cloning
1) an unfertilised egg cell is taken and the nucleus is removed
2) a complete set of chromosomes is inserted from an adult body cell (from the animal you want to clone)
3) the egg is stimulated by an electric shock causing it to divide like an embryo
4)when it is a ball of cells, it is implanted into an adult female (the surrogate mother) to grow
hope this helps
1) an unfertilised egg cell is taken and the nucleus is removed
2) a complete set of chromosomes is inserted from an adult body cell (from the animal you want to clone)
3) the egg is stimulated by an electric shock causing it to divide like an embryo
4)when it is a ball of cells, it is implanted into an adult female (the surrogate mother) to grow
hope this helps
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#17
(Original post by Nihaj)
Yes this is Aqa
So for this question lets take a cow for example
Firstly a body cell is taken from a cow. A egg cell is taken from a different cow. The nuclei from both cells are removed. The nucleus from the body cell is placed in the empty egg cell (because we removed the nucleus). Then the cell is shocked as it starts the cell division. The cell will divide and form an embryo which is then inserted into the womb of the surrogate mother.
Yes this is Aqa
So for this question lets take a cow for example
Firstly a body cell is taken from a cow. A egg cell is taken from a different cow. The nuclei from both cells are removed. The nucleus from the body cell is placed in the empty egg cell (because we removed the nucleus). Then the cell is shocked as it starts the cell division. The cell will divide and form an embryo which is then inserted into the womb of the surrogate mother.
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(Original post by LaliG)
Do you know if we have to learn all the indicator species and what they do? E.g. fresh water shrimp, mayfly larvae..
Do we need to know what they are affected by and stuff ?
Thank you
Do you know if we have to learn all the indicator species and what they do? E.g. fresh water shrimp, mayfly larvae..
Do we need to know what they are affected by and stuff ?
Thank you
These are free good indicators:
-Lichen
-Bloodworms
-Mayfly Larvae
Depending on the type of Lichen species we are able to see how much pollution is in the air. (Lichen are used to indicate the amount of sulphur dioxide in the air)
Bloodworms indicate high levels of water pollution.
Mayfly Larvae indicates low levels of water pollution.
Bloodworms and Mayfly Larvae are also indicators of the concentration of dissolved oxygen in water.
Oxygen levels are high in unpolluted water.
Oxygen levels are low in polluted water.
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#19
(Original post by lou2471)
1) an unfertilised egg cell is taken and the nucleus is removed
2) a complete set of chromosomes is inserted from an adult body cell (from the animal you want to clone)
3) the egg is stimulated by an electric shock causing it to divide like an embryo
4)when it is a ball of cells, it is implanted into an adult female (the surrogate mother) to grow
hope this helps
1) an unfertilised egg cell is taken and the nucleus is removed
2) a complete set of chromosomes is inserted from an adult body cell (from the animal you want to clone)
3) the egg is stimulated by an electric shock causing it to divide like an embryo
4)when it is a ball of cells, it is implanted into an adult female (the surrogate mother) to grow
hope this helps
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#20
(Original post by Nihaj)
A stimulus is detected by the receptor cells. The receptor sends an electrical impulse to the sensory neurone. This electrical impulse travels through the sensory neurone till it reaches the synapse. The electrical impulse can't travel across the synapse (A synapse is the junction between two neurones) so instead a chemical is released which travels across from the sensory neurone to the relay neurone (across the synapse). An electrical impulse is then passed from the relay to the motor neurone. The motor neurone sends this electrical signal to the effector (muscle) which causes the reflex.
A stimulus is detected by the receptor cells. The receptor sends an electrical impulse to the sensory neurone. This electrical impulse travels through the sensory neurone till it reaches the synapse. The electrical impulse can't travel across the synapse (A synapse is the junction between two neurones) so instead a chemical is released which travels across from the sensory neurone to the relay neurone (across the synapse). An electrical impulse is then passed from the relay to the motor neurone. The motor neurone sends this electrical signal to the effector (muscle) which causes the reflex.
Also, (being picky, I know) you could add that the response is the muscle contraction.
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