*(REVISE) FOR LAST POST

Analogy of frame-shift mutation

one sentences

CAN YOU BUY CAT FOR HER SON

after insertion only one alphabet , A at CAT in the sentence,

CAN YOU BUY ACA TFO RHE RSO N

we can't read that sentence

after delete only one word, C at CAT in the sentence

CAN YOU BUY ATF ORH ERS ON

we can't read that sentence

*peringatan analogi ini untuk kefahaman sahaja ianya tidak boleh digunakan dalam peperiksaan

7.3: CHROMOSOMAL MUTATION

• Definition: Abnormalities ~ in chromosomal structure (chromosome aberration) & changes in

chromosome number (aneuploidy / euploidy)

• Chromosomal mutations take place when the number of chromosomes changes or when structural

changes occur in the chromosomes

• Classification chromosomal mutation

i) Chromosomal aberration (structural of chromosomal change)

ii) Chromosomal number alteration

- Aneuploidy

- Euploidy (polyploidy)

Chromosomes aberration

• Changes in the chromosomes structure, are most frequently formed during mitosis or meiosis

• Rearrangement a certain segment @ parts of chromosome

• 4 types of chromosomal aberration

i) Translocation

ii) Deletion (segmental deletion)

iii) Inversion

iv) Duplication

Translocation

Translocation : involves a region of a chromosome breaking off and rejoining either the other end of the same

chromosome or another non-homologous chromosome

• e.g. Robertsonian translocation

• Robertsonian translocation involves breaks at the extremes ends of the short arms of two

nonhomologous chromosomes (13, 14, 15, 21 and 22)

• Named after the American insect geneticist W.B.Robertson

• Also called whole-arm translocation or centric-fusion translocation

Deletion

Deletion : the lost of 1 segment containing 1 or more genes

• When the chromosome breaks at two places and lead to the loss of the middle segment

• The segment lost may contain one or more genes

• The remaining end of chromosome will join again and become shorten

• Genetic disease: Cri du chat syndrome (usually mentally retarded and cries like a cat mewing)

• Loss of a small part of the short arm of chromosome 5

• Cri du chat is a rare syndrome (1 in 50,000 live births) caused by a deletion on the short arm of

chromosome 5.

• The name of this syndrome is French for "cry of the cat," referring to the distinctive cry of children with

this disorder.

• The cry is caused by abnormal larynx development, which becomes normal within a few weeks of birth.

• Infants with cri du chat have low birth weight and may have respiratory problems.

• Some people with this disorder have a shortened lifespan, but most have a normal life expectancy.

• Where does the abnormal chromosome 5 come from? In 80 percent of the cases, the chromosome

carrying the deletion comes from the father's sperm.

Inversion

Inversion : a region of a chromosome breaks off and rotates through 180° before rejoining the

chromosome

Duplication

Duplication : a region of a chromosome becomes duplicated; an additional set of genes exists

• Whena single locus or a large piece of a chromosome is present more than once in the genome

Alteration of chromosomes number

• Type of the alteration of chromosomal number

i. aneuploidy

ii. euploidy / polyploidy

• Human somatic cells containing a number of chromosomes which is not a multiple of 23 are called

aneuploids

Aneuploidy

                                                      

• Aneuploidy is a condition in which the number of chromosomes is abnormal due to extra or missing

chromosomes, in other words, it is a chromosomal state where the number of chromosomes is not a

multiple of the haploid set.

• Normal diploid species have 2n chromosomes, where n is the number in the haploid set.

• Aneuploid individuals would have 2n-1 chromosomes (monosomy), 2n+1 chromosomes (trisomy), or

some other such arrangement.

• A change in the number of chromosomes can lead to a chromosomal disorder. Aneuploidy is common in

cancerous cells.

• Aneuploidy occurs during cell division when the chromosomes do not separate properly between the two

cells

Disjunction: chromosomes separated to the opposite poles during meiosis

Non disjunction : failure of pair of chromosome to separate and to move to the opposite poles

both sets of chromosomes pass to the same pole of the cell

Cause of aneuploidy

Nondisjunction in Anaphase I & II

Nondisjunction in Anaphase I and II (meiosis)

                                       

• Half the daughter cells produced have an extra chromosomes (n+1) whilst the other half have a

chromosome missing (n-1)

• Fusion gametes between chromosome (n+1) and normal gamete (n), produced embryo with

chromosome (2n+1) : Trisomy; eg. Down’s syndrome

• Fusion gametes between chromosome (n-1) and normal gamete (n), produced embryo with

chromosome (2n-1) : Monosomy; eg. Turner Syndrome

CHAPTER 7: MUTATION

Explain mutation

• A mutation is a change in the amount, arrangement or structure of the DNA of an organism.

• Mutations produce sudden and distinct differences between individuals cause alternation of

chromosome.

• Alteration of chromosome number or structure cause some genetic disorders such as Sickle Cell

Anemia and Down Syndrome

• Mutation can occurring in gamete cells or somatic cells.

i) gamete cells

are inherited, It passed to subsequent generations as part of the hereditary endowment of the

games derived from that cell.

ii) somatic cells

can only be inherited by daughter cells produced by mitosis.

• A mutant is an individual or new genetic character arising or resulting from an instance of mutation the

blue lobster is an example of a mutant.

• Type of mutation

i) spontaneous mutation

- Mistakes happen spontaneously during DNA replication, repair and recombination

- eg. nondisjunction

ii) induced mutation

- Organism exposed to mutagen

What is mutagen ?

• a mutagen  is a physical or chemical agent that changes the genetic material

• Operate either by causing changes in the DNA of the genes or by causing chromosome damage

• type of mutagen

i) Physical agent

Ultraviolet ray

Ionizing radiation (X-ray, gamma ray, alpha particles, neutron and electron)

ii) Chemical agent

eg. Colchicine (usually to treat rheumatic complaints, especially gout)

Ethidium bromide

CLASSIFICATION OF MUTATION:

GENE MUTATION (POINT MUTATION)

• Producing alterations in the sequence of DNA nucleotide.

• involve only one or a few base pair in the coding sequence.

• Arise due to spontaneous pairing errors that occur during DNA replication,

• Arise due to mutagens like radiation or chemicals cause damage to the DNA.

• As a result :

- Change the amino acid sequence and thus, changes the protein

- Different protein produced as the effect of mutation may not function as normal

• Classify gene mutation

i) Base substitution

ii) Base insertion

iii) Base deletion

iv) Base inversion

• mutation of base deletion and insertion make cause frame shift mutation

• Alteration of gene mutation cause some genetic disorders such as Sickle Cell Anemia

Classification of Gene mutation:

Base substitution :

• One or a few base pairs in the nucleotide sequences in genes is substitute

• Changes in base sequence – results in changes of codon (UAU/UGU)

• 3 base/ nucleic acid = 1 codon (coding for 1 amino acid)

• Changes in codon:-

a) amino acid changes (missense mutation)

b) changes a codon to stop codon (nonsense mutation)

• Missense mutations are those that still code for an amino acid but change the indicated amino acid eg.

Sickle Cell Anemia.

• Nonsense mutations change an amino acid codon into a stop codon, nearly always leading to a

nonfunctional protein.

Sickle cell Anemia

• mutant Hbs cause defective red blood cell. The cells are shaped like a crescent or sickle

• occurs more commonly in people regions where malaria is or was common. there is a survival value in

carrying only a single sickle-cell gene Those with only one of the two alleles of the sickle-cell disease are

more resistant to malaria, since the infestation of the malaria plasmodium is halted by the sickling of the

cells which it infests.

• sickle shape body produces abnormally shaped red blood cells.

• Hbs stiff & tend to accumulate in small capillary, Hb is not efficient of transporting oxygen

                                                  

Base deletions

• Loss of 1 or a few base pairs in the nucleotide sequences in genes

• mutation of base deletion make cause frame shift mutation

Normal Mutant

lost of T base during replication of DNA

DNA chain AGA GTC TTC AGA GCT TCG

transcript

mRNA UCU CAG AAG UCU CGA AGC

translation

code of amino acid Ser Gln Lys Ser Arg Ser

frame-shift happen

Base inversion

• 2 base pairs or more are inverted in nucleotide sequence

Normal Mutant

inverted in nucleotide sequence

DNA chain AGA GTC TTC AGA TGC TTC

transcript

mRNA UCU CAG AAG UCU ACG AAG

translation

code of amino acid Ser Gln Lys Ser Thr Lys

Frame-shift Mutations

• Involve insertion/deletion of a base pair or more into the nucleotides sequence of DNA

• Many of these deletions/insertion start in the middle of a codon

• Shifting the reading frame by one or two bases

• Frame shift mutations cause the gene to be read in the wrong three base groups (codon)

• From the mutation point,

• It abrupt the coding sequence of amino acid.

• Changes in codons results in changes in amino acids

• Different polypeptide is produced

• Effect ~ usually harmful to human

• E.g.: Major Thalasemia (mutant homozygote alleles)

9 steps to learn ANY language

Part 1

EditGetting Down to the Basics

1. 
   1
   Know your learning style. This is the single most important thing you need to know when starting to learn a language. Everyone learns differently, especially when it comes to languages. You'll need to figure out if you learn best through repetition, through writing down the words or through listening to a native speaker.

   • Decide if you're a visual, auditive or kinesthetic learner. A trick to figuring out which you are is this: Pick a couple words from your language and read them over a few times. If you can remember them the next day you're probably a visual learner. If not, have someone else read the words to you several times without seeing them yourself. If you can remember them the next day, you're most likely an auditive learner. If this doesn't work, read and write the two words, repeat them out loud, listen to them read by someone else, associate memories and feelings with them. If you can remember them the next day, you're probably a kinesthetic learner.^[1]
     
   • If you've learned languages in the past, go over what you learned then and try to figure out what worked best for you. What helped you learn? What didn't? When you've sorted this out you'll be ready to start learning the language.
     
2. 
   2
   Learn pronunciation. Even if a language has the same alphabet as yours that does not mean the pronunciation is always the same. (Just ask a Polish person how to pronounce the letters "cz.")

   • The Foreign Service Institute offers free online language learning materials, which include audio recordings which help with learning pronunciation and the Duolingo website offers useful pronunciation tips (as well as quality, free language learning services).^[2]
3. 
   3
   Pay attention to the grammar. This is probably the most important part of the language besides the vocabulary. "Paul want Mary go store" may communicate an idea, but it is not at all correct English. If you do not pay attention to grammar, you can sound equally incomprehensible in another language.

   • Look at the structure of the language and how the articles work (masculine, feminine, neutral). Getting a handle on the structure of the language will help you understand how it fits together once you start learning different words
   • Ensure you know how to express questions, affirmative and negative statements in the past, present and future using the 20 most common regular and irregular verbs.
4. 
   4
   Memorize 30 words and phrases each day. Within 90 days this means you will have memorized about 80% of the language. Start with the most common words. Memorization is half the battle and there are many different ways to memorize.

   • You can practice writing each word a dozen times, which will get you used to using the word itself.
     
   • Try using the words in various and different sentences. This will help you practice the words and make it easier to recall the words when you need them.
   • Don't forget to keep practicing the words once you move on to memorizing other words. If you don't practice them you will forget them.
5. 
   5
   Practice the alphabet. Especially if you're learning a language which operates on a different alphabetical system, you will need to know what the letters look like and how they operate.

   • Try associating images with each letter and sound, so that your brain will have an easy path to remembering the letter and the sound that accompanies it. For instance: In Thai the letter "า" is pronounced "ah." If you're a guy you can think of this as the path taken by your pee if you're urinating against a tree and the accompanying sigh you make as you relieve yourself. Associations can be as simple, or as silly as you want, as long as they help you remember.^[3]
   • You may also have to accustom yourself to reading from right to left, or from the top of the page to the bottom. Start simple and work up to more difficult things like newspapers and books.

Part 2

EditPracticing the Language

1. 
   1
   Listen. Listening to the language, be it through movies or television shows, through audio language coursesor music can help you retain the words you're trying to learn. Just listening won't help, though. You will need to repeat the words and speak them yourself.

   • The method called "shadowing" is considered by many polyglots (people who know many languages) as a useful technique. Put your headphones in and go outside. While you play the language, walk briskly. As you're walking briskly repeat aloud and clearly what you're hearings. Repeat, repeat, repeat. This will help you connect kinetics (movement) with the language and to retrain your focus so that you aren't obsessing about memorization.^[4]
   • Use audio books or audio language lessons. You can listen to these while you commute to work or while you jog around the park. This will help your listening skills. Repeat listening to short segments of 30 seconds to one minute until you feel you have complete comprehension. Sometimes you may have to listen to the course completely more than twice to fully catch all that it teaches.
     
   • Watch television shows and movies without the subtitles. This includes soap operas, news shows, even shows you already know that have been dubbed into the language. It's a fun way to practice and apply your knowledge.
     
   • Listen to music in the language you're learning. This is fun and easy and will, hopefully, keep you interested in what you're doing. Just put on some music while you're doing the dishes or going for a walk and pay attention to the words in the songs You might also want to listen to classic songs because they are easy to catch on to.
     
2. 
   2
   Read in your chosen language. Start off with simpler books and, as you get better, move on to more difficult ones. Challenge yourself to reading without a dictionary and let yourself puzzle the meanings out by yourself.

   • Children's books are a great place to start because these books are meant to teach children how to read and understand their language. Since you are just starting out, you will want to start somewhere easy.
     
   • Find books that you have enjoyed in your native language and read them in the language you are trying to learn. Your knowledge of the book's contents will help you decipher the words and keep you interested in the reading material.
   • Try popular magazines or newspapers in the language you wish to learn. Choose a topic that interests you. Magazines are a good way to learn common idioms in context. Magazine and newspaper articles cover a variety of subjects, and they're generally much shorter than reading an entire book.
     
   • You can purchase a quality dictionary of the language you wish to learn or you can use a free online language dictionary. When you encounter a new word, highlight it in the dictionary. Then, copy the word, definition, and an example sentence using the word into a notebook. Then, study the notebook. This activity helps you think in the language.
   • Sometimes a picture dictionary is helpful for learning common nouns for some languages. Use a picture dictionary for Japanese, for example, because many of their words carry a variety of meanings, as in English.
3. 
   3
   Speak with native speakers. If you don't speak the language, you are unlikely to learn it well and keep it in your memory. There are programs that link people learning a language and native speakers via Skype. If you can't do that, look around your city or town. Chances are someone will be able to direct you to a person who can help you practice. A language school is a good place to start.

   • Learn some idioms, proverbs and expressions. As your level advances, learn about some of the idioms and even slang in the language. Even if you don't end up using them much, they will help you recognize and understand these elements when you hear or read them.
   • Don't be embarrassed if you aren't speaking the language properly yet. It takes time to learn.
   • This step cannot be stressed enough. If you don't practice speaking the language you won't be fluent in it. Talk to native speakers, get a friend to learn the language with you and practice with them, talk back to the t.v.
4. 
   4
   Practice. Do not hesitate to speak the language in public and with native speakers. It will be helpful in improving your mastery. Also, don't be ashamed to allow other people to correct you if you pronounce something wrong. No one knows everything. Welcome constructive criticism. Test your knowledge at every social occasion you have.

   • Keep watching movies and and television shows. If you like soccer, for example, watch it in Spanish to keep the language fresh in your memory. Make sure to yell at the t.v. when the game isn't going your way.
   • Challenge yourself to think in the language you are attempting to learn.

How to Cope With Stress at School

 

Making Studying Stress-Free

 

Learn to manage your time more efficiently. With piles and piles of homework staring at you, sometimes being told to "calm down" or "relax" seems like a big joke. To cut through the heap of work you have to do and to make it seem more manageable, start planning out your time accordingly. Conquer a little bit every night so you're never left with a tower of work to climb by tomorrow.

• Start with the hardest things first. You don't have to finish the entire task now, but just getting the ball rolling will make it seem so much more manageable when you go to finish it in a few days.^[1]
• Take little opportunities to get work done. If you're waiting for the bus, whip out those flashcards. When you go to review tonight, that 5 or 10 minutes of prep will help you finish that much sooner.

Get organized. If your locker looks like a tornado blew through it, or your study desk at home is really just a horizontal closet without hangers, it's no wonder school stresses you out. It's just too hard to figure out ;

1. 5
   Don't procrastinate. All of the above steps have a common element: not procrastinating. Think about it this way: if you had to lose 20 pounds, and you had one month to do it, would you want to wait until the last few days to start dieting? Nope. That's a recipe for disaster. Think of your grades the same way – you can't put tasks off and expect good results and peace of mind.
   

   • The sooner you're on top of your game, the more you can breathe. You'll feel in control, and that's really what stress is about. Whether you have a million things to do or just a few things to do, it's feeling in control that's the kicker. And if you don't procrastinate and hop to it, that sense of control will be a lot easier to get a hold of.
2. 
   6
   Stay realistic. Let's be honest: kids in school are getting more and more stressed at an earlier and earlier age.^[2] They're worrying about college in grade school, in addition to trying to be a rock star at virtually everything. When it all starts stressing you out, take a breather. Maybe you won't get into Oxford. Maybe you won't be football captain. Maybe you will get an A- this semester. And life will go on. It's school – not the Hunger Games.
   

   • If you're trying to do it all, you may need to take a step back and abandon an extra-curricular or two. School is hard enough as it is – you can't be an athlete, a musician, an ambassador, a volunteer, and a thespian on top of it. What's one thing you could live without? The extra free time may make everything else that much easier.

Part 2

Eliminating Stress

1. 
   1
   Evaluate the source. Stress at school can come from a number of different places. Here's a few things to consider:
   

   • Peer-induced stress. This is when stress comes from your classmates. It could be because you feel they're outperforming you, you feel you're just different from them and won't be accepted, or even because they're bullies.
   • Parent-induced stress. This happens when your parents don't make reasonable demands of you and your academic performance. They are constantly harping on you to get better grades and be an ideal student.
   • Teacher-induced stress. This occurs when you don't jive with a specific teacher, or when you feel like your teachers are disapproving. Hopefully this only occurs with one teacher, but it could occur with many.
   • Self-induced stress. This kind of stress comes from the inside. You've put demands on yourself to try to be "good enough" or "valuable" in your own mind. This can be one of the easiest and hardest types of stress to tackle.
2. 
   2
   Get rid of the source (as much as possible). Taking those four sources listed above, what do you do to make them better?
   

   • Peer-induced stress. In this situation, you could try to change classes or pick up a different after-school activity with different people. Worst case scenario, you could change schools.
   • Parent-induced stress. This involves a very honest conversation with your parents that could possibly also involve your teachers or school counselor. Communication needs to be established between the two of you that doesn't make you feel negative – and they need to know that that's how their view makes you feel.
   • Self-induced stress. This involves a change of thinking. It's easy because you're in control, but it's difficult because mind-control isn't exactly easy as pie. You have to make a conscious effort to think more positively and more globally, realizing that the world is much bigger than your performance at school.
3. 
   3
   Talk to your counselor. If school is getting to you and you feel about an inch away from pulling out all your hair, your school counselor may be a natural source of good advice. What's more, he or she may be able to point you in a new direction, giving you opportunities for destressing that you didn't even know existed (like taking a class online, or getting credit for volunteering). They can also be the go-between for you and your parents or teachers.
   

   • If you don't have a relationship with your school counselor already, there's no better time than the present. They're there to help you – and they could even be a network connection for schools in the future.
4. 
   4
   Start thinking positively. Sure, it's easier said than done – but once you do it, you'll never go back. A positive mindset can keep stress at bay, making even the most difficult (or the most boring) of tasks seem okay. After all, you have so much going for you, and life is going to be awesome once this pile of homework is done (and eventually, it will be). With a new, fresh outlook on life, nothing can stop you.
   

   • If this is particularly difficult for you, start trying to be positive in just 10 minute increments. When you wake up in the morning, think of a few things you're excited about and grateful for to put you in an upbeat mood. In time, this will become a habit and be virtually effortless.
5. 
   5
   Spend time doing something you love. Everyone needs a passion to keep their inner fire burning strong. We all need something that makes us happy. If life is all work on no play, you'll be on a one-way ride to misery and self-resentment. So make whatever it is you love a priority. When what you love is a part of your life, everything else that's stressful can just fall into the background.
   

   • Don't feel guilty about it, either. Paul Allen, Michael Dell, Bill Gates – none of them graduated from college and they turned out pretty okay.^[3] Your performance in school isn't the end-all-be-all of your life, so don't devote 24/7 to it. Spend your best years enjoying them, not resenting them.

Part 3

Taking Care of Your Mental Health

1. 
   1
   Keep a routine. Do your brain a favor and stick to the same routine every school day. Get home, grab a snack, sit down to study, take a Facebook break, sit down to study some more, and then go party like it's the weekend. When you have a plan to stick to, it's easier to relax. There's no longer the question of, "When am I going to study for this?" or, "When do I have time for that?" With a routine, you'll know exactly how your time fits together.
   

   • Humans, in general, like to know what to expect. It's why we turn to others for their opinions and recommendations. It allows our brains to relax and calm down, accepting the fact that we can only take in so much information at a time. If you give yourself a routine to stick to, your brain will be able to quit being on high alert and take a mental breather.
   • Keeping a schedule can help you tackle one hurdle at a time, and as a result, feel more in control. Get a schedule from a supply store or make one yourself and hang it up in your room. Write down everything you need to do in order not to miss deadlines – and this way you can let it leave your brain; you've got it down on paper!
2. 
   2
   Get enough sleep. Students should at least sleep 7 to 8 hours a day to make it easier for them to cope with stressful situations, and some even need around 9 hours a day to function at 100%. Not only will this help with you staying alert, focusing, and likely getting better grades, but it will also result in you being less stressed-out, less irritable, and not as tense.
   

   • Research shows that not getting enough sleep isn't just about being tired. It also leads to memory problems, decreased alertness and performance, a poorer quality of life, and even makes you prone to injury.^[4]
   • If you want good grades, you need sleep. Resist the urge to cram – it won't do you any good. Studies show that students who cram actually do worse than students who opted for sleep instead. Your memory of the night before won't work anyway when you're a zombie during the test.^[5]
3. 
   3
   Exercise regularly. Exercising at least 30 minutes a day can help alleviate stress, tension, and boost confidence.^[6] It releases endorphins – those little happy-makers in your brain that keep you feeling good. So get on the treadmill, lift some weights, or just dance it out. Sometimes your mind takes cues from your body, and this is definitely one of those moments.
   

   • This is a good excuse to do those more mundane chores, too. Offer to take Fluffy for a walk, wash your dad's car, or get to meticulously scrubbing the tub. Even little sessions of calorie-burning are helpful – and you may be able to make a buck off your parents while doing it.
4. 
   4
   Set aside time for relaxation. Everyone needs free time to do things that make them happy and keep them stress-free. If you're going, going, going 24 hours a day, you're going to burn out. After a studying session, make sure you spend some time making yourself feel good: listen to relaxing music, take a long bath, watch a romantic movie, do yoga, or meditate. Relaxing for at least an hour per day can help you get rid of that stress building up inside.
   

   • It doesn't have to be something stereotypically "relaxing." If playing an intense, zombie-destroying video game helps you relax, do that. If reading a chilling horror novel gets you in the zen zone, do that. If you enjoy it and it makes you less tense, what's not to like?
5. 
   5
   Make time for fun, too. Take a step back and remember to have fun with friends. Without socialization, it's easy to go a little crazy. If you don't, you'll wind up a little miserable, which is ultimately demotivating for you and bad for your grades. Having fun can actually keep you going.
   

   • If you feel like you "don't have time" for being social, turn it into something academic. It can be helpful to have a group study session where you can talk and joke, but also get things done. It will be entertaining and instructional at the same time – the best of both worlds.