Biology Paper 1 Edexcel 2019

i made it up. i wrote that theres a shorter distance for impulses to travel to get to the brain so they dont need to be sped up using myelin sheaths. its probs wrong anyways

Original post by bossman765

what did u lot say for why brain neurones dont need to by myleniated

Reply 81

Lrl456

15

i got 1.3 picometres

Original post by AuTalon

Was it 130nm for that cell size conversion one?

Reply 82

SchmuckOff

20

Original post by bossman765

what did u lot say for why brain neurones dont need to by myleniated

Mylein sheath speeds up transmission speads which are needed for those in the reflex arc to react quickly whereas those in the brain don't need to react quickly as they're bypassed in the reflex arc

Reply 83

bossman765

11

oh so its more energy efficient for them not have mylein sheath, that acc makes sense i said there is a snapse after brain neuron, so the mylein sheath is not needed whereas the motor neuron goes straight to effector, without a synapse so its myleniated but i think u r right

Original post by haleema_123

i made it up. i wrote that theres a shorter distance for impulses to travel to get to the brain so they dont need to be sped up using myelin sheaths. its probs wrong anyways

Reply 84

haleema_123

6

omg yhh i didnt write that :frown:

Original post by SchmuckOff

Mylein sheath speeds up transmission speads which are needed for those in the reflex arc to react quickly whereas those in the brain don't need to react quickly as they're bypassed in the reflex arc

Reply 85

cerys03

12

for the 0.15% question, i divided the 30,000 (or whatever that number was) by 0.15 to get 1% then multiplied by 100 to get 100%

(edited 4 years ago)

Reply 86

haleema_123

6

no im wrong lol

Original post by bossman765

oh so its more energy efficient for them not have mylein sheath, that acc makes sense i said there is a snapse after brain neuron, so the mylein sheath is not needed whereas the motor neuron goes straight to effector, without a synapse so its myleniated but i think u r right

Reply 87

Lrl456

15

aayyyyyy yes i put that too!

Original post by SchmuckOff

Mylein sheath speeds up transmission speads which are needed for those in the reflex arc to react quickly whereas those in the brain don't need to react quickly as they're bypassed in the reflex arc

Reply 88

bossman765

11

put that as well

Original post by Lrl456

aayyyyyy yes i put that too!

Reply 89

itsyafavboo

3

Original post by Lella99x

Is this higher?

yeh g

Reply 90

helloitsemily02

3

Ye

Original post by RyanJA

lens x?

YYe

Reply 91

the_icy_goldfish

16

no because the 300000 is equal to the 0.15% so why would you times it if its equal?

Original post by Lukebates99

Can’t u just times by 0.0015?

Reply 92

DanyBOY16

2

Original post by kate_howard_1

yeah, it should have been 6.5/50,000 which gives u an answer. Multiply it by 10 (i divided) then by 1000.

**** i did 6.6

Reply 93

Esos

1

Original post by Lella99x

What did you say for the last question

The neurons release a chemical neurotransmitter which allows the neuron to be passed across the synapse. Erm something like that but elaborated

Reply 94

Sarahashmeade

5

The original amount x 0.015 = the number it gave

The original amount = the number it gave/ 0.015

I think that’s how, I did it wrong but I think that’s right

Original post by Lella99x

What was the awnser for the 0.15% population one and how do you do it

Reply 95

AP5461

4

Couple of Answers: Meiosis produces 4 genetically different gametes. These are haploid cells. Mitosis produces two genetically identical daughter diploid cells.
Bacterium cell has cell wall, flagellum and chromosomal DNA.
Cones
Normal vision is when the light rays are focused on to the retina
Lens X to cure short sightedness as the light rays are focused in front of the retina.
Cerebrum.
Vaccination produces memory lymphocytes which produces the antibodies that attach onto the antigens of the pathogen.
Antibiotic resistance is when the bacteria develop this characteristic from mutations in their DNA. Chracteristic passed onto the future generations and new offspring.
Myelin sheath acts as an electrical insulator to speed up electrical impulses which is useful in quick responses to a stimuli, for example touching a hot object.
Synapse is the connection between two neurones, which causes chemicals called neurotransmitters to be released. They help the impulses flow in one direction and pass the electrical impulses from the sensory to relay and the relay to motor neurone.
1.3 for magnification.
3.1 for halpoid nucleus.
Add Benedict reagent to a food sample and heat in water bath at 75 degrees. Blue to brick red.
4.8 rate of reaction.
8.95 X 10^7( people got to the power of 8, but 89500000 is to the power of 7).
Other standard form was to the power of 8.
Gonnorhoea caused by the transfer of bodily fluids, for example semen and vaginal. Avoid sharing unsterilised needles, men wearing a condom when having sex, female protection and isolation for individuals to avoid sexual contact. Men infection rate much higher than women.

A and B dominant and 25% chance likely child will have a blood type 0. 0 is a recessive blood type and two of these will need to be expressed in the genotype for it to be expressed.

(edited 4 years ago)

Reply 96

bossman765

11

ngl you know you put flagellum for bacteria, not all bacteria have flagellum, so its osmetimes not on markshemes, its a risky bet man
and i think yo can put cereberum or cereberal cortext same thing, and i got that same as u for the others

Original post by AP5461

Couple of Answers: Meiosis produces 4 genetically different gametes. These are haploid cells. Mitosis produces two genetically identical daughter diploid cells.
Bacterium cell has cell wall, flagellum and chromosomal DNA.
Cones
Normal vision is when the light rays are focused on to the retina
Lens X to cure short sightedness as the light rays are focused in front of the retina.
Cerebrum.
Vaccination produces memory lymphocytes which produces the antibodies that attach onto the antigens of the pathogen.
Antibiotic resistance is when the bacteria develop this characteristic from mutations in their DNA. Chracteristic passed onto the future generations and new offspring.
Myelin sheath acts as an electrical insulator to speed up electrical impulses which is useful in quick responses to a stimuli, for example touching a hot object.
Synapse is the connection between two neurones, which causes chemicals called neurotransmitters to be released. They help the impulses flow in one direction and pass the electrical impulses from the sensory to relay and the relay to motor neurone.
1.3 for magnification.
3.1 for halpoid nucleus.
Add Benedict reagent to a food sample and heat in water bath at 75 degrees. Blue to brick red.
4.8 rate of reaction.
8.95 X 10^7( people got to the power of 8, but 89500000 is to the power of 7).
Other standard form was to the power of 8.
Gonnorhoea caused by the transfer of bodily fluids, for example semen and vaginal. Avoid sharing unsterilised needles, men wearing a condom when having sex, female protection and isolation for individuals to avoid sexual contact. Men infection rate much higher than women.

A and B dominant and 25% chance likely child will have a blood type 0. 0 is a recessive blood type and two of these will need to be expressed in the genotype for it to be expressed.

Reply 97

Lrl456

15

you can use flagellum for bacteria cus a vast majority do it will be on the mark scheme

Original post by bossman765

ngl you know you put flagellum for bacteria, not all bacteria have flagellum, so its osmetimes not on markshemes, its a risky bet man
and i think yo can put cereberum or cereberal cortext same thing, and i got that same as u for the others