USING THE BRAILLE SCIENCE CODE - rnib.org.uk · km2 (kilometres) Km+2 20 km2 #bj km+2 12.25 km2 #ab1be km+2 Volume Print Braille Examples mm3 (millimetres3) Mm+3 9 mm3 #i mm+3 ...

CH2CH2

USING THE BRAILLE

SCIENCE CODE

THE BRAILLE SCIENCE CODE FOR SCHOOLS

This document is intended for use by all those who are involved with theteaching of Science to students who use Braille as their main medium forcommunication. The document is based on the Braille code used in theUnited Kingdom for transcribing Science from print text into Braille, andincludes advice about various transcription issues. The official statement ofthe UK Science code is contained in the BAUK document “Braille ScienceNotation” which may be obtained from the BAUK web site, www.bauk.org.uk,or in hard copy from RNIB.

The document contains examples of most of the common units and chemicalsymbols found in the Key Stage 3, Key stage 4, AS and A2 curricula. The examples are not meant to be exhaustive but should act as a guide tosolving the common problems which occur when transcribing Sciencenotation into Braille. There is also a section for those wishing to transcribethe notation found in Genetics. The code in this section is one that has beenused successfully but has never been adopted as a standard by BAUK.

The document was produced by the following members of the RNIB/VIEWScience Curriculum Group.

Frances Betts, Norman Brown, Rowena Curley, Susan Epstein, SusanParker, Cath Smith and Hillary Unwin.

We would like to thank the staff at RNIB New College and the members ofRNIB/VIEW Science Curriculum Group for their comments during thedrafting of this document.

1

CONTENTS1. Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Key stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Mass and force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Key stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Radiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

AS and A2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2. Compound units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Additional useful units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3. Chemistry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Chemical symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Chemical formulae. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Ionic symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Atomic structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Subatomic particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Electronic structure/configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 15Chemical equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16State symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Reversible reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Covalent bonds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

AS and A2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Organic chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Shorthand for organic chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . 22Molecular formulae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Structural formulae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Graphical display formulae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Electrochemical shorthand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254. Physics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Key stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Circuit diagram symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

GCSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Circuit diagram symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

5. Genetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2

UNITS

For details of layout see the Braille Science Notation and BrailleMathematics Notation booklets.

Units are coded according to the print by placing a dot 6 before each capital letter.

Dot 5,6 is only required:1. Before a lower case or upper case single letter unit symbol

(eg m or T), standing alone or with just an index or punctuation.2. Before the abbreviation for second in combined unit, where

necessary to avoid ambiguity.3. Before a lower case letter which is followed by an upper case letter

at the beginning of an abbreviation.

The following are examples of the most commonly used symbols at KS 3,KS 4 and AS and A2 levels.

Key Stage 3

Length

Print Braille Examples

mm (millimetres) Mm 9 mm #i mm

4.5 mm #d1e mm

cm (centimetres) Cm 3 cm #c cm

150.5 cm #aej1e cm

m (metres) ;m 6 m #f ;m

12 m #ab ;m

1.5 m #a1e ;m

km (kilometres) Km 20 km #bj km

12.25 km #ab1be km

3

Area


mm2 (millimetres2) Mm+2 9 mm2 #i mm+2

4.5 mm2 #d1e mm+2

cm2 (centimetres2) Cm+2 3 cm2 #c cm+2

150.5 cm2 #aej1e cm+2

m2 (metre2) ;m+2 6 m2 #f ;m+2

1.5 m2 #a1e ;m+2

km2 (kilometres) Km+2 20 km2 #bj km+2

12.25 km2 #ab1be km+2

Volume


mm3 (millimetres3) Mm+3 9 mm3 #i mm+3

4.5 mm3 #d1e mm+3

cm3 (centimetres3) Cm+3 3 cm3 #c cm+3

150.5 cm3 #aej1e cm+3

m3 (metre3) ;m+3 6 m3 #f ;m+3

12 m3 #ab ;m+3

1.5 m3 #a1e ;m+3

l (litre) ;l 20 l #bj ;l

or 12.25 l #ab1be ;l

L (Litre) ;,l 50 L #ej ;,l

ml (millilitre) Ml 50 ml #ej ml

4

Time


s (second) ;s 6 s #f ;s

min (minute) M9 3 min #c m9

Mass and force


g (gram) ;g 6 g #f ;g

kg (kilogram) Kg 3 kg #c kg

N (Newton) ;,n 15.5 N #ae1e ;,n

Temperature


°C (degrees celsius) 0,c 6°C #f0,c

Note the unit is unspaced.

K (Kelvin) ;,k 8K #h ;,k

Electrical


V (Volt) ;,v 6 V #f ;,v

A (Ampere) ;,a 3 A #c ;,a

mA (milliamp) ;m,a 5 mA #e ;m,a

5

For KS 4 add the following

Electrical


Ω (Ohm) _w 6 Ω #f _w

W (Watt) ;,w 3 W #c ;,w

MW (megawatt) ,,mw 6 MW #f ,,mw

J (Joule) ;,j 4.2 J #d1b ;,j

kJ (kilojoule) ;k,j 35 kJ #ce ;k,j

Note the use of the capital Greek letter sign (dots 4,5,6)

Radiation


λ (lambda) .l 6 λ #f .l

Hz (Hertz) ,hz 50 Hz #ej ,hz

α (alpha) .a α-particle .a-"picle

β (beta) .b β-particle .b-"picle

γ (gamma) .g γ-particle .g-"picle

Note the use of the lower case Greek letter sign (dots 4,6)

Time


ms (milliseconds) ms 50 ms #ej ms

6

For AS and A2 add the following

Length


μm (micrometre) .mm 6 μm #f .mm

nm (nanometres) Nm 3 nm #c nm

Volume


μl (microlitre) .ml 6 μl #f .ml

dm3 (decimetre3) Dm+3 3 dm3 #c dm+3

Pressure


Pa (Pascals) ,pa 6000 Pa #fjjj ,pa

kPa (kilopascals) ;K,pa 6 kPa #f ;k,pa

MPa (megapascals) ,m,pa 2.5 MPa #b1e ,m,pa

7

COMPOUND UNITS


Nm (Newton metres) ,n'm 3 Nm #c ,n'm

g/l (grams per litre) ;g_/l 10 g/l #aj ;g_/l

or

gl-1 (grams per litre) ;g'l+;-1 5 gl-1 #e ;g'l+;-1

m/s metres per second ;M_/s 30 m/s #cj ;m_/s

or

ms-1 (metres per second) ;M's+;-1 20 ms-1 #bj ;m's+;-1

m/s2 (metres per second2) ;m_/s+2 25 m/s2 #be ;m_/s+2

or

ms-2 (metres per second2) ;M's+;-2 25 ms-2 #be ;m's+;-2

Nm-2 (Newtons per metre squared) ,n'm+;-2 25 Nm-2 #be ,N'm+;-2

or

N/m2 (Newtons per square metre) ,n_/m+2 25 N/m2 #be ,n_/m+2

mph (milesper hour) ;mph 60 mph #fj ;mph

kph (kilometresper hour) ;kph 35 kph #ce ;kph

Note the use of a dot 3 separator where the oblique sign is not used.

8

Additional useful units


pH ;p,h pH 7 ;p,h #g

molarity ,m 2M #b,m

pH can be spaced or unspaced from a following number, according to print.

M is always unspaced from a preceding number.

9

CHEMICAL SYMBOLS

A single letter symbol is preceded by dot 6.

A two letter symbol is preceded by dot 5.

Examples:

Level Print Braille

All levels H ,h

C ,C

O ,O

Na "na

Mg "Mg

Al "Al

Note that, as with units and elsewhere, a single letter symbol possiblyfollowed by a subscript number, standing alone in ordinary text requires adots 5,6 also.

Example

Print Braille

H ;,h (when standing alone)

10

Chemical formulae

All two letter symbols must be preceded by dot 5.

Dot 6 only needs to be used at the start of the formula if the first symbol is aone letter symbol. It does not have to be repeated in the middle of a formula.

Subscripts are written in the lower case.

Key Stage 3

Print Braille

H2O ,H2O

CO2 ,CO2

MgO "MgO

KCl ,K"Cl

CaCl2 "Ca"Cl2

CuSO4 "CuSO4 (no need for dot 6)

CaCO3 "CaCO3 (no need for dot 6)

CO ,co

CoO "coo (no need for dot 6)

11

Formulae with brackets

Round brackets ( ), use maths brackets (gh and ar contractions).

Square brackets [ ], use maths brackets (of and with contractions).

Level Print Braille

Key Stage 3 Ca(OH)2 "Ca<oh>2

Key Stage 4 (NH4)2SO4 <,nh4>2so4

Cu(NO3)2 "Cu<no3>2

A Level (CH3)3OH <,ch3>3oh

[Fe(OH)3(H2O)3] ("fe<oh>3<h2o>3)

12

Ionic symbols

Use the appropriate number of + or – signs unspaced from the symbol.

Level Print Braille

Key Stage 4 H+ ,h;6

K+ ,k;6

Zn2+ "Zn;66

Al3+ "Al;666

F- ,f;-

O2- ,o;--

N3- ,n;---

NH4+ ,nh4;6

OH- ,oh;-

SO42- ,so4;--

A Level Complex ions [Fe(H2O)6]2+ ("fe<h2o>6);66

[Cr(OH)6]3- ("cr<oh>6);---

N.B. The Braille Science Code includes the alternative notation for ionic charges of +/- 2 or greater using a superscript number followed by a + ;6 or – ;- sign.

Print Braille

Mg2+ "Mg+#b;6

Al3+ "Al+#c;6

SO42- ,so4+#b;-

The notation using the appropriate number of + or – signs is preferred byteachers.

Braille producers for examinations can use the alternative!

13

Atomic Structure

Atomic mass numbers and atomic numbers are given as superscript + and subscripts * respectively in front of the symbol. Use lower case numbers.

Level Print Braille

Key Stage 4 and A Level 42He +4*2"he

2713Al +27*13"al

Subatomic particles

Use lower case letters.

Level Print Braille

Key stage 4 p (proton) ;p

e (electron) ;e

e- (electron showing charge) ;e;-

n (neutron) ;n

A Level 11p +1*1;p

–0–1e +0*;-1;e

10 n +1*0;n

14

Electronic Structure/configuration

Key Stage 4

Print Braille

Na (2,8,1) "na <#b#h#a>

Ca (2,8,8,2) "ca <#b#h#h#b>

A Level

No need to use lower case letter sign except in front of “d” (this avoidsconfusion with the number 4) . Keep unspaced throughout.

1s22s22p4

#as+2#bs+2#bp+4

1s22s22p63s23p63d74s2

#as+2#bs+2#bp+6#cs+2#cp+6#c;d+7#ds+2

15

Chemical equations

Use + (;6) unspaced from the following item.

The spaced on both sides is preferred to = unspaced from the following item.

Print Braille

3o

Word equations

Here are some examples.

Magnesium + oxygen magnesium oxide

magnesium ;6oxyg5 3o magnesium oxide

Calcium carbonate + hydrochloric acid calcium chloride + carbon dioxide + water

calcium c>bonate ;6hydro*loric acid

3o calcium *loride ;6c>bon dioxide

;6wat]

Carbon dioxide + water (chlorophyll, light)

glucose + oxygen

c>bon dioxide ;6wat] 3o+<*lorophyll1

li<t> glucose ;6oxyg5

See pages 19 and 20 for more information about words above and belowthe arrow.

16

Symbol equations

Equations should begin in cell 5, with runovers in cell 7.

If a runover is needed, finish the previous line with a dot 5.

All Levels

C + O2 CO2

,c ;6,o2 3o ,co2

2NH4OH + H2SO4 (NH4)2SO4 + 2H2O

#b,nh4oh ;6,h2so4 3o <,nh4>2so4"

;6#b,h2o

or:

#b,nh4oh ;6,h2so4 3o"

<,nh4>2so4 ;6#b,h2o

17

State symbols in equations

Write after the formula, leaving one space.

Key Stage 4 and A Level

Print Braille

(s) (solid) 7;s7

(l) (liquid) 7;l7

(g) (gas) 7;g7

(aq) (aqueous) 7aq7

C(s) + O2(g) CO2(g)

,c 7;s7 ;6,o2 7;g7 3o ,co2 7;g7

2H2(g) + O2(g) 2H2O(l)

#b,h2 7;g7 ;6,o2 7;g7 3o"

#b,h2o 7;l7

NaOH(aq) + HCl(aq) NaCl(aq) + H2O(l)

"naoh 7aq7 ;6,h"cl 7aq7 3o"

"na"cl 7aq7 ;6,h2o 7;l7

H+(aq) + OH-(aq) H2O(l)

,h;6 7aq7 ;6,oh;- 7aq7 3o"

,h2o 7;l7

Mg(g) Mg2+(g) + 2e-

"mg 7;g7 3o "mg;66 7;g7 ;6#b;e;-

Cl(g) + e- Cl-(g)

"cl 7;g7 ;6e;- 3o "cl;- 7;g7

18

Reversible reactions/equilibrium

The arrow should be spaced on both sides.


Print Braille

53e

N2 + 3H2 2NH3

,n2 ;6#c,h2 53e #b,nh3

Information above/below arrows


Use superscript sign (+) immediately after the arrow. Use round brackets toenclose two or more items of information.

H2S400°C

º H2 + S

,h2s 53e+#djj0,c ,h2 ;6,s

N2 + 3H2 2NH3

,n2 ;6#c,h2 53e+<#djj0,c1

#bjj atm> #b,nh3

19

400°C, 200 atmº

If there is information above and below the arrow in print, Braille entirely assuperscript.

N2 + 3H2 2NH3

,n2 ;6#c,h2 53e+<#djj0,c1

#bjj atm1 hab] process> #b,nh3

Covalent bonds


Bond Print Braille

Single H—H ,h@h

Double O O ,o^o

Triple N≡N ,n_n

20

400°C, 200 atm

Haber Process

A Level Chemistry

Example Print Braille

delta + δ+ .d;6

Enthalpy change ΔH _d,h

Enthalpy of formation ΔHf _d,h*f

Enthalpy of combustion ΔHc _d,H*c

Equilibrium constants Kc ,k*c

Kp ,k*p

Kw ,k*w

Ka ,k*a

Rate constant k ;k

Standard reduction potential E ,e+0

(n.b. this is not an agreedconvention but is an acceptablematch to the print)

21

Acceptable shorthand for Organic Chemistry

Example Print Braille

Alkyl radical R ,R

Aryl group, C6H5 Ar "Ar

(n.b. this is only in the context of OrganicChemistry and must not be confused with thesymbol for the element argon, Ar)

Methyl group, CH3 Me "me

Ethyl group, C2H5 Et "et

Molecular formulae

Follow the rules for chemical formulae.

Print Braille

C2H6 ,c2h6

C3H7OH ,c3h7oh

CH3COCl ,ch3co"cl

C2H5COOCH3 ,C2H5COOCH3

22

Structural formulae

Follow the rules for chemical formulae.

Print Braille

CH3CH3 ,CH3CH3

CH3CHOHCH3 ,CH3CHOHCH3

CH3CHClC(CH3)2CH3 ,CH3CH"CLC<CH3>2CH3

Structural formulae showing bonds

Use code for bonds.

Print Braille

CH3—CH3 ,CH3@CH3

CH3—CH2—Br ,CH3@CH2@"BR

(CH3)2C——O <,CH3>2C^O

23

Displayed graphical formulae

Whilst this is covered in para 19 onwards in the Chemistry section of theBraille Science Notation, for school use these are best done using raiseddiagrams with the bonds represented by solid lines. For double and triplebonds the gap between the lines should be no less than 3mm.


Print Braille

24

H

H C H

H

,H

,H ,C ,H

,H

H H

C C

H H

,H ,H

,C ,C

,H ,H

H C C H ,H ,C ,C ,H

Electrochemical cell shorthand

A Level

There is no agreed Braille convention for this. The following is only asuggestion which bears some resemblance to the print layout.

Print

Zn(s) ⎮ Zn2+(aq) Cu2+(aq) ⎮ Cu(s)

Suggested Braille:

Use _ unspaced to the right to represent vertical line

Use __ unspaced to the right to represent double, dashed vertical lines

"zn 7;s7 _"zn;66 7aq7 __"cu;66 7aq7

_"cu 7;s7

25

PHYSICS

Circuit diagrams

The following symbols are used to produce raised circuit diagrams. Where a symbol is thought to be unfamiliar the name of the component isoften added in Braille under the symbol.

Key Stage 3

Print Braille

Switch (open)

Cell

Resistor

Variable resistor

Lamp

Lamp (alternative version)

26

Print Braille

Voltmeter

Ammeter

Motor

All of these symbols will need to be enlarged by a factor of at least twobefore they can be used by a student working by touch alone.

For GCSE

Print Braille

Fuse

Battery

Diode

27

A

V

M

,v

,m

,A

For GCSE (continued)

Print Braille

Capacitor

Thermistor

Light emitting diode (LED)

Light dependent resistor (LDR)

These examples are not exhaustive but they should give a good idea of howthe majority of symbols can be enlarged and presented in a tactile form.Where there might be doubt about a particular example the name can beprovided below the symbol in Braille.

Mathematical formulae used in Physics should follow the advice given in theBraille Mathematics Notation (BAUK).

28

GENETICS

The study of Genetics requires students to solve problems which require astandard code in print. There is at present no Braille equivalent but thefollowing has been used successfully with students working towards GCSEand A level examinations.

The key to the code involves the use of the dot 6 capital letter sign toidentify upper case letters in the code and the dots 56 letter sign to identifythe lower case letters. Genetics problems have a particular layout whichforms part of the assessment criteria. The following examples use Braille buthave the layout that is used in print. This means that students’ answers canbe easily transcribed and anyone with a limited amount of Braille knowledgecan follow the steps used by the student to solve the problem.

In each example the print translation is provided as a guide to both contentand layout.

The first example shows the steps used in a standard Mendel monohybridcross. This type of cross is found in the syllabi for GCSE.

29

Example 1

The original parents are from two pure breeding strains where the dominantallele codes for a tall individual and the recessive allele codes for a dwarfindividual. The dominant allele is represented by T and the recessive alleleby t.

P>5ts tall ;8 dw>f

Parents tall x dwarf

G5otypes ,T,T ;t;t

Genotypes TT tt

Gametes ,T ;t

Gametes T t

(fspr+ ,T;t

Offspring Tt

All (fspr+ >e tall 2c ;,T is dom9ant

6;t4

All offspring are tall because T is dominant to t.

See the next page for the next stage.

30

31

If ;! (fspr+ n[ 9t]bre$4

If these offspring now interbreed.

P>5ts ,T;t ;8 ,T;t

Parents Tt x Tt

Gametes ,T & ;t ,T & ;t

Gametes T and t T and t

(fspr+

Offspring

,T ;t

T t

,T ,T,t ,T;t

T TT Tt

;t ,T;t ;t;t

t Tt tt

? gives "o ,T,T & two ,T;t 9dividuals

b !y w 2 tall 9dividuals z ;,T is

dom9ant4 "O ;t;t 9dividual is al

produc$4 ? 9dividual is dw>f4

This gives one TT and two Tt individuals but they will be tall individuals as T is dominant. One tt individual is also produced. This individual is dwarf.

Please note that the Braille table above is identical to the Punnet square used by those working in print. Some teachers use arrows to link the various gametes to form the offspring. This process will not work for students working in Braille and is confusing for many partially sighted students. Therefore teachers should be encouraged to use the Punnet square method.

32

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t A2

leve

l syl

labi

. Her

e tw

o ge

nes

with

two

alle

les

are

invo

lved

in th

e cr

oss.

Let o

ne g

ene

be fo

r flo

wer

col

our w

ith tw

o al

lele

s, R

for r

ed p

etal

s an

d r f

or w

hite

pet

als.

R is

dom

inan

t to

r. Th

e ot

her g

ene

is fo

r pla

nt h

eigh

t, T

for t

all a

nd t

for d

war

f. T

is d

omin

ant t

o t.

In th

is e

xam

ple

the

pare

nts

are

hete

rozy

gous

for b

oth

gene

s ie

thei

r gen

otyp

es a

re R

rTt.

P>5ts

,R;r,T;t

;8

,R;r,T;t

Par

ents

RrT

tx

RrT

t

Gametes

,R,T ,R;t ;r,T & ;r;t

,R,T ,R;t ;r,T & ;r;t

Gam

etes

RT

Rt

rTan

drt

RT

Rt

rTan

drt

33

(fspr+

Offs

prin

g

,R,T

,R;t

;r,T

;r;t

RT

Rt

rTrt

,R,T

,R,R,T,T

,R,R,T;t

,R;r,T,T

,R;r,T;t

RT

RR

TTR

RTt

RrT

TR

rTt

,R;t

,R,R,T;t

,R,R;t;t

,R;r,T;t

,R;r;t;t

Rt

RR

TtR

Rtt

RrT

tR

rtt

;r,T

,R;r,T,T

,R;r,T;t

;r;r,T,T

;r;r,T;t

rTR

rTT

RrT

trr

TTrr

Tt

;r;t

,R;r,T;t

,R;r;t;t

;r;r,T;t

;r;r;t;t

rtR

rTt

Rrtt

rrTt

rrtt

? gives #i r$ fl[]$ tall plants1 #c r$ fl[]$ dw>f

plants1 #c :ite tall plants & #a :ite dw>f plant4

This

giv

es 9

red

flow

ered

tall

plan

ts, 3

red

flow

ered

dw

arf p

lant

s, 3

whi

te ta

ll pl

ants

and

1 w

hite

dw

arf p

lant

.

Example 3

Some geneticists use a single capital letter to distinguish the gene and asuperscript letter to label the allele. This can be seen in crosses involvingthe fruit fly, Drosophila and sometimes in the genetics of the ABO bloodgroups. In blood groups the gene is given the letter I and the groups arelabelled as IA, IB and Io. In Braille these would be ,i+,a, ,i+,band ,i+;o. This notation takes up considerably more space (especially in a dihybrid cross). It may be necessary to modify questions to eliminate theletter for the gene leaving the letters for the alleles which can then be usedas shown earlier.

34

Other titles in this series:

TC20209 Using the Braille French Code

TC20910 Using the Braille German Code

TC20911 Using the Braille Spanish Code

TC21086P Using the Braille Mathematics Code

ISBN

976 1 85878 820 3

TC21085P

2008

Produced by RNIB on behalf of

RNIB/VIEW Science Curriculum Group

USING THE BRAILLE SCIENCE CODE - rnib.org.uk · km2 (kilometres) Km+2 20 km2 #bj km+2 12.25 km2 #ab1be km+2 Volume Print Braille Examples mm3 (millimetres3) Mm+3 9 mm3 #i mm+3 ...

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