Alguns animais, como o peixe elétrico, conseguem gerar corre

Alguns animais, como o peixe elétrico, conseguem gerar corrente elétrica pela simples migração de íons de metais alcalinos através de uma membrana. O órgão elétrico desse peixe é formado por células chamadas de eletroplacas, que são similares às musculares, mas não se contraem. Essas células são discos achatados, nos quais uma das superfícies é inervada por terminações nervosas colinérgicas. Quando estimuladas, apenas a superfície inervada é despolarizada. Milhares de eletroplacas empilham-se em série formando conjuntos que, por sua vez, se dispõem em paralelo.

O esquema abaixo, representando esses conjuntos, detalha também a estrutura básica da eletroplaca e mostra os potenciais de repouso da membrana e a sua inversão na face inervada, quando o nervo é estimulado.

Como também ocorre na célula muscular, a inversão do potencial da superfície inervada da eletroplaca é conseqüência da rápida difusão para o interior dessa célula do seguinte íon:

Na+

K+

Ca++

Mg++

Língua Inglesa | 2.05 Adjetivos

(UDESC)

What it says:

What it really means:

"All procedures were approved by the Internal Ethics Review Board"

"Please don't come protest outside our lab."

“Samples were treated with 0.03% sodium citrate buffer for 60.3 min. at 37.4 deg with 20.5 mg/kg poly(I:C) dissolved in 0.97% sterile PBS volume of 8.2 ml/kg”

"If you deviate from this by one number, it's not my fault when you can't replicate my results."

“The solution was isolated using catalyst CH2CI2/Et20 4:1 in 71% yield as a mixture of 1 H NMR (CDCI3) 7.90 (ddd, J=3.2, 5.2, 20.4 Hz, 1H), 7.30 (dd, J=0,8, 2.0 Hz, 1H)”

"My advisor has no idea what this means."

“Measurements were performed with –1.74<<1.74 around a field of 1.16T with (pT )/pT 0.5% pT /GeV + 1.5%"

"I don't know why this works but this is how the previous grad student taught me to do it."

"Experimental kits from a commercial vendor were used and applied according to the manufacturer's instructions."

"We wasted a lot of time trying to do it ourselves, but it turned out you can just buy it."

"Filter and gain settings varied with experimental conditions and objectives."

"We twiddled the knobs until it worked."

"Simulation parameters were chosen based on empirically realistic values."

"We made stuff up."

"The treated preparation was incubated overnight."

"I went to have a few beers with my friends."

"Analysis was performed using a commercially available software package."

"I put the numbers into this magic box and out came my thesis!"

"Statistical significance was assessed using the Student's T Test."

"Yes, all that just to verify it with something they teach in High School now."

www.phdcomics.com

Accessed on: March 25^th, 2012.

Mark the correct alternative which replaces the underlined expression in: “We made stuff up”.

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