1 00:00:01,486 --> 00:00:03,773 - [Voiceover] The fourth of the major macromolecules 2 00:00:03,773 --> 00:00:05,971 is gonna be nucleic acid. 3 00:00:05,971 --> 00:00:09,751 Now there are two primary types of nucleic acids. 4 00:00:09,751 --> 00:00:13,001 You have DNA, or deoxyribonucleic acid, 5 00:00:14,983 --> 00:00:17,900 and you have RNA, ribonucleic acid. 6 00:00:19,542 --> 00:00:22,741 Now you notice both of them have the term ribonucleic acid, 7 00:00:22,741 --> 00:00:24,324 just DNA has deoxy. 8 00:00:25,404 --> 00:00:29,091 Reason being, deoxy, without oxygen. 9 00:00:29,091 --> 00:00:32,424 There's one less oxygen molecule in DNA. 10 00:00:35,072 --> 00:00:38,957 But both these are meant to store genetic information. 11 00:00:38,957 --> 00:00:43,124 The DNA is primarily located within the nucleus of a cell. 12 00:00:44,207 --> 00:00:45,958 It's kind of the brain of a cell, 13 00:00:45,958 --> 00:00:48,746 the main structural point of the cell. 14 00:00:48,746 --> 00:00:51,247 It contains all this genetic information, 15 00:00:51,247 --> 00:00:53,386 controls what's going on. 16 00:00:53,386 --> 00:00:57,407 While the RNA can be found it the nucleus, 17 00:00:57,407 --> 00:01:00,974 but it can also be found throughout the rest of the cell. 18 00:01:00,974 --> 00:01:04,474 It's these two nucleic acids that are used 19 00:01:05,582 --> 00:01:09,309 to provide information to make a protein. 20 00:01:09,309 --> 00:01:12,591 Well if you're wondering what's protein do in our bodies? 21 00:01:12,591 --> 00:01:15,827 All your muscles are tons of protein, 22 00:01:15,827 --> 00:01:18,369 bones, most of your organs, 23 00:01:18,369 --> 00:01:22,966 your skin, the vast majority of tissue in your body, 24 00:01:22,966 --> 00:01:27,049 that's structural tissue, is going to be protein. 25 00:01:29,087 --> 00:01:33,567 Now these nucleic acids, doesn't matter if it's DNA or RNA, 26 00:01:33,567 --> 00:01:37,666 they are long chains that just keep going one after another. 27 00:01:37,666 --> 00:01:40,051 What they're doing, is they're repeating these sub-units, 28 00:01:40,051 --> 00:01:44,769 basic building blocks referred to as nucleotides. 29 00:01:44,769 --> 00:01:47,852 Now DNA has four primary nucleotides. 30 00:01:49,405 --> 00:01:51,664 The same thing with RNA. 31 00:01:51,664 --> 00:01:55,813 The only difference is they don't quite have the same four. 32 00:01:55,813 --> 00:01:58,885 These nucleotides are the building blocks. 33 00:01:58,885 --> 00:02:01,805 It's long chains of these nucleotides 34 00:02:01,805 --> 00:02:04,836 that make up the nucleic acids. 35 00:02:04,836 --> 00:02:09,281 Now the nucleotide is made up of three primary components. 36 00:02:09,281 --> 00:02:11,622 You have a five carbon sugar. 37 00:02:11,622 --> 00:02:15,389 Now this five carbon sugar will be dependent 38 00:02:15,389 --> 00:02:16,556 on DNA or RNA. 39 00:02:18,377 --> 00:02:22,970 If you're looking at DNA, this sugar is deoxyribose. 40 00:02:22,970 --> 00:02:26,657 If you're looking at RNA, it's ribose. 41 00:02:26,657 --> 00:02:30,824 Both deoxyribose and ribose are your simple sugars. 42 00:02:32,253 --> 00:02:37,132 Those are monosaccharides from your carbohydrates. 43 00:02:37,132 --> 00:02:39,105 Then you have a nitrogenous base 44 00:02:39,105 --> 00:02:41,447 and a phosphate group. 45 00:02:41,447 --> 00:02:43,789 Now the sugar and phosphate group 46 00:02:43,789 --> 00:02:46,872 are always the same in DNA or in RNA. 47 00:02:47,772 --> 00:02:51,479 The way you get different types of nucleotides 48 00:02:51,479 --> 00:02:54,479 is by changing the nitrogenous base. 49 00:02:55,333 --> 00:02:59,500 There's a total five different types of nitrogenous bases 50 00:03:00,745 --> 00:03:02,912 found between DNA and RNA. 51 00:03:04,886 --> 00:03:08,136 In DNA, we have these four nucleotides. 52 00:03:10,552 --> 00:03:13,459 We have the difference being nitrogenous base. 53 00:03:13,459 --> 00:03:17,064 On the left, you can see is Adenine. 54 00:03:17,064 --> 00:03:19,198 Kinda has a little green shading there. 55 00:03:19,198 --> 00:03:20,386 Now the colors mean nothing. 56 00:03:20,386 --> 00:03:23,547 They're just given you there for illustration purposes. 57 00:03:23,547 --> 00:03:27,895 But Adenine, making that one type of nucleotide. 58 00:03:27,895 --> 00:03:30,562 Then Thymine, Cytosine, Guanine. 59 00:03:32,483 --> 00:03:36,650 Those are the four different types of nucleotides for DNA. 60 00:03:40,486 --> 00:03:42,589 So the structure of DNA, 61 00:03:42,589 --> 00:03:45,586 using those four different nucleotides, 62 00:03:45,586 --> 00:03:49,003 build up all of the nucleic acids of DNA. 63 00:03:50,032 --> 00:03:53,782 The deoxyribonucleic acid is double-stranded. 64 00:03:55,606 --> 00:03:58,347 That means there are two strands of DNA 65 00:03:58,347 --> 00:04:02,136 that are always being held together. 66 00:04:02,136 --> 00:04:05,527 And we already said Adenine, Guanine, Cytosine, Thymine, 67 00:04:05,527 --> 00:04:08,761 those are the four different nitrogenous bases. 68 00:04:08,761 --> 00:04:11,545 With a deoxyribose sugar. 69 00:04:11,545 --> 00:04:13,356 And when they start pairing, 70 00:04:13,356 --> 00:04:16,262 it's always Adenine, Thymine, 71 00:04:16,262 --> 00:04:18,109 Guanine, Cytosine. 72 00:04:18,109 --> 00:04:20,776 So it's always A and T, C and G. 73 00:04:22,290 --> 00:04:26,068 If for some reason you end up with an A bound to a C, 74 00:04:26,068 --> 00:04:29,151 or a G bound to a T, that's an error. 75 00:04:30,045 --> 00:04:32,671 That could potentially cause some pretty serious problems, 76 00:04:32,671 --> 00:04:35,004 even with one little mix up. 77 00:04:36,280 --> 00:04:38,130 So your body, thankfully, is pretty good 78 00:04:38,130 --> 00:04:40,220 at making sure it doesn't produce errors. 79 00:04:40,220 --> 00:04:41,902 If it does produce an error, 80 00:04:41,902 --> 00:04:46,069 there's special mechanisms to catch or correct errors. 81 00:04:48,507 --> 00:04:52,127 So here's a artist's rendition of DNA. 82 00:04:52,127 --> 00:04:53,895 Towards the top of the picture, 83 00:04:53,895 --> 00:04:57,128 you can see how it's spiraling, creating this helix. 84 00:04:57,128 --> 00:04:59,502 Or this double helix. 85 00:04:59,502 --> 00:05:01,433 Towards the bottom, they flattened it out, 86 00:05:01,433 --> 00:05:04,834 just to show how things are going together. 87 00:05:04,834 --> 00:05:06,349 You can see the base pairs. 88 00:05:06,349 --> 00:05:07,266 C, G, T, A, 89 00:05:08,152 --> 00:05:09,069 A, T, C, G. 90 00:05:09,951 --> 00:05:14,422 They're always in the middle of a double strand. 91 00:05:14,422 --> 00:05:18,482 While the outside edges, see all the purple area, 92 00:05:18,482 --> 00:05:21,310 phosphate, sugar, phosphate, sugar. 93 00:05:21,310 --> 00:05:22,310 Alternating. 94 00:05:23,322 --> 00:05:25,370 So you can kinda think of it like a ladder. 95 00:05:25,370 --> 00:05:28,906 The rungs of the ladder are the base pairs. 96 00:05:28,906 --> 00:05:30,997 Those nitrogenous bases. 97 00:05:30,997 --> 00:05:32,596 While the outside edge of the layer 98 00:05:32,596 --> 00:05:34,520 that hold the rungs together 99 00:05:34,520 --> 00:05:38,372 is alternating sugars and phosphate groups. 100 00:05:38,372 --> 00:05:41,746 And this is the basic idea for all DNA. 101 00:05:41,746 --> 00:05:43,545 Now to have DNA be different, 102 00:05:43,545 --> 00:05:46,010 you'd change up the base pairs. 103 00:05:46,010 --> 00:05:48,467 Those nitrogenous pairs. 104 00:05:48,467 --> 00:05:51,295 Because as you read DNA, it's like reading a sentence. 105 00:05:51,295 --> 00:05:53,260 You read them in order. 106 00:05:53,260 --> 00:05:54,816 Depending on the order, 107 00:05:54,816 --> 00:05:58,233 depends on what protein will be produced. 108 00:06:00,318 --> 00:06:02,460 So how about some RNA? 109 00:06:02,460 --> 00:06:04,460 RNA is ribonucleic acid. 110 00:06:05,376 --> 00:06:08,257 Same basic principle as DNA, 111 00:06:08,257 --> 00:06:11,986 but now we're only single-stranded. 112 00:06:11,986 --> 00:06:15,428 So instead of that double strand we had in DNA, 113 00:06:15,428 --> 00:06:18,011 we have a single strand in RNA. 114 00:06:19,528 --> 00:06:24,322 The sugar is ribose instead of that deoxyribose. 115 00:06:24,322 --> 00:06:26,449 So RNA has ribose. 116 00:06:26,449 --> 00:06:31,284 And it still has Adenine, Guanine, Cytosine as the bases, 117 00:06:31,284 --> 00:06:33,284 but now it added Uracil. 118 00:06:34,694 --> 00:06:37,027 Uracil is only found in RNA. 119 00:06:40,117 --> 00:06:42,617 You cannot find Uracil in DNA. 120 00:06:45,728 --> 00:06:49,561 So which nitrogenous base is only found in DNA 121 00:06:51,753 --> 00:06:53,003 and not in RNA? 122 00:06:55,775 --> 00:06:58,723 Remember in DNA, it was C binds to G, 123 00:06:58,723 --> 00:06:59,752 Cytosine, Guanine, 124 00:06:59,752 --> 00:07:00,585 A binds to 125 00:07:02,574 --> 00:07:03,491 T, Thymine. 126 00:07:05,212 --> 00:07:08,086 So Thymine is only in DNA. 127 00:07:08,086 --> 00:07:10,336 Well Uracil is only in RNA. 128 00:07:12,920 --> 00:07:14,800 And here's a strand of RNA. 129 00:07:14,800 --> 00:07:15,907 You can see it's the same thing, 130 00:07:15,907 --> 00:07:18,743 just looks like half of a DNA strand. 131 00:07:18,743 --> 00:07:21,943 You have nitrogenous bases on one side. 132 00:07:21,943 --> 00:07:23,579 Then you have this back bone 133 00:07:23,579 --> 00:07:26,733 alternating sugar, phosphate, sugar, phosphate. 134 00:07:26,733 --> 00:07:29,273 It's going phosphate, ribose, phosphate, ribose, 135 00:07:29,273 --> 00:07:31,324 phosphate, ribose. 136 00:07:31,324 --> 00:07:35,138 So same basic layout, just a few different components. 137 00:07:35,138 --> 00:07:37,115 We have ribose, for sure, 138 00:07:37,115 --> 00:07:39,532 and we have Uracil as a base. 139 00:07:42,361 --> 00:07:45,804 So we already mentioned that they store genetic information. 140 00:07:45,804 --> 00:07:48,465 But why do you need two different types of nucleic acids? 141 00:07:48,465 --> 00:07:49,798 Why DNA and RNA? 142 00:07:51,429 --> 00:07:55,596 Well the reason being DNA stores instruction in the nucleus. 143 00:07:57,373 --> 00:07:59,673 It's kind of like the memory center. 144 00:07:59,673 --> 00:08:03,001 It keeps the information in every cell. 145 00:08:03,001 --> 00:08:06,531 But DNA cannot leave the nucleus. 146 00:08:06,531 --> 00:08:07,596 It can't do anything. 147 00:08:07,596 --> 00:08:09,973 It's stuck in there. 148 00:08:09,973 --> 00:08:13,556 So DNA will help make instructions for RNA. 149 00:08:16,717 --> 00:08:20,884 RNA then will carry those instruction from the nucleus 150 00:08:21,726 --> 00:08:24,508 out to the rest of the cell. 151 00:08:24,508 --> 00:08:27,658 When it carries it out to the rest of the cell, 152 00:08:27,658 --> 00:08:30,908 it can initiate the making of proteins. 153 00:08:32,138 --> 00:08:35,668 Cause remember, ultimate goal here was to make proteins 154 00:08:35,668 --> 00:08:38,835 for structural components of the body. 155 00:08:40,018 --> 00:08:43,439 Protein, that's what makes our life go on. 156 00:08:43,439 --> 00:08:45,612 It's things that give us structure. 157 00:08:45,612 --> 00:08:49,085 Proteins can help with different chemical reactions. 158 00:08:49,085 --> 00:08:53,252 Proteins can take part in a majority of what our bodies do. 159 00:08:54,534 --> 00:08:56,951 So this DNA to RNA to protein 160 00:08:57,856 --> 00:09:00,575 is always found in that sequence. 161 00:09:00,575 --> 00:09:03,325 DNA cannot directly make protein. 162 00:09:04,471 --> 00:09:06,641 That's why RNA is so important. 163 00:09:06,641 --> 00:09:10,818 It bridges the gap between the DNA and the protein. 164 00:09:10,818 --> 00:09:13,318 So DNA to RNA, RNA to protein. 165 00:09:15,317 --> 00:09:19,394 And that little passage right there is very, very important 166 00:09:19,394 --> 00:09:22,389 as far as how our bodies work. 167 00:09:22,389 --> 00:09:24,723 Because without the DNA, you can't make the RNA. 168 00:09:24,723 --> 00:09:26,898 Without RNA, you can't make protein. 169 00:09:26,898 --> 00:09:28,981 So DNA to RNA to protein. 170 00:09:32,440 --> 00:09:35,840 But then we have some of this not really a nucleic acid, 171 00:09:35,840 --> 00:09:38,007 but it looks very similar. 172 00:09:39,172 --> 00:09:40,172 We have ATP. 173 00:09:42,042 --> 00:09:43,959 Adenosine triphosphate. 174 00:09:45,079 --> 00:09:46,558 Now, think Adenosine. 175 00:09:46,558 --> 00:09:48,810 That was one of those bases. 176 00:09:48,810 --> 00:09:49,875 That's right. 177 00:09:49,875 --> 00:09:52,625 Adenosine was a nitrogenous base. 178 00:09:53,937 --> 00:09:58,401 What we've done now is taken that Adenosine nitrogenous base 179 00:09:58,401 --> 00:10:01,316 and attached it to three phosphates. 180 00:10:01,316 --> 00:10:03,649 Hence the term triphosphate. 181 00:10:04,969 --> 00:10:08,302 ATP is the energy source for your cells. 182 00:10:10,144 --> 00:10:12,844 Now do you eat ATP directly? 183 00:10:12,844 --> 00:10:13,706 No, not really. 184 00:10:13,706 --> 00:10:18,012 You eat carbohydrates, lipids, proteins, nucleic acids. 185 00:10:18,012 --> 00:10:21,512 But your body takes that fuel that you eat 186 00:10:22,478 --> 00:10:24,561 and converts it into ATP. 187 00:10:27,356 --> 00:10:30,856 Because ATP is what the cells of your body 188 00:10:31,694 --> 00:10:33,611 can utilize for energy. 189 00:10:36,097 --> 00:10:38,689 It's the bonds that are made. 190 00:10:38,689 --> 00:10:41,191 So you have three phosphate groups. 191 00:10:41,191 --> 00:10:44,705 The bonds between each of the phosphates 192 00:10:44,705 --> 00:10:46,788 contain potential energy. 193 00:10:48,266 --> 00:10:51,734 Oh think, okay, potential energy, potential energy. 194 00:10:51,734 --> 00:10:54,567 Potential energy is stored energy. 195 00:10:55,800 --> 00:10:59,810 Kinetic energy is the energy of movement. 196 00:10:59,810 --> 00:11:03,477 So these bonds are storing potential energy. 197 00:11:05,267 --> 00:11:08,767 When you break a bond, you release energy. 198 00:11:09,630 --> 00:11:12,213 So ATP, adenosine triphosphate, 199 00:11:14,789 --> 00:11:16,539 can go to ADP plus P. 200 00:11:17,983 --> 00:11:20,244 So it's the extra phosphate. 201 00:11:20,244 --> 00:11:22,911 You've broken one phosphate off. 202 00:11:23,852 --> 00:11:28,323 By breaking that phosphate, you released energy. 203 00:11:28,323 --> 00:11:32,490 That released energy can perform work inside the cell. 204 00:11:35,903 --> 00:11:40,070 Here's a schematic of that process of releasing energy. 205 00:11:40,941 --> 00:11:44,941 Now we take ATP, adenosine and three phosphates, 206 00:11:46,265 --> 00:11:47,515 then add water. 207 00:11:48,351 --> 00:11:50,026 Why do we add water? 208 00:11:50,026 --> 00:11:52,192 Remember, if you add water to break a bond, 209 00:11:52,192 --> 00:11:54,616 it's called hydrolysis. 210 00:11:54,616 --> 00:11:56,866 Hydro, water, lysis, break. 211 00:11:58,849 --> 00:12:02,286 So by simply adding a water molecule, 212 00:12:02,286 --> 00:12:04,119 we can break the bond. 213 00:12:05,034 --> 00:12:08,534 By breaking that bond, it releases energy. 214 00:12:10,825 --> 00:12:14,658 And we end up with adenosine diphosphate, ADP, 215 00:12:15,917 --> 00:12:18,917 and extra phosphate floating around. 216 00:12:20,433 --> 00:12:24,415 But that's not quite as useful in your body. 217 00:12:24,415 --> 00:12:28,248 So somehow you have to now obtain more energy. 218 00:12:29,636 --> 00:12:33,090 You obtain more energy to put that phosphate 219 00:12:33,090 --> 00:12:35,423 back on to the ADP molecule. 220 00:12:38,380 --> 00:12:41,867 So come from energy that's stored in your body. 221 00:12:41,867 --> 00:12:44,959 Glycogen, storage of carbohydrates. 222 00:12:44,959 --> 00:12:47,126 Or fat, storage of lipids. 223 00:12:48,244 --> 00:12:51,487 If you take any one of those energy storages, 224 00:12:51,487 --> 00:12:54,697 break them down a little bit to release energy. 225 00:12:54,697 --> 00:12:57,858 That energy will go into putting the phosphate 226 00:12:57,858 --> 00:12:59,025 back into ATP. 227 00:13:02,134 --> 00:13:05,051 But that, well, now what you're doing, 228 00:13:05,051 --> 00:13:08,718 by actually adding energy, you remove water. 229 00:13:12,260 --> 00:13:15,012 When you remove water to form a bond, 230 00:13:15,012 --> 00:13:17,429 that's dehydration synthesis. 231 00:13:19,222 --> 00:13:22,579 So the foods you've eaten will provide the energy 232 00:13:22,579 --> 00:13:24,662 to make the bonds of ATP. 233 00:13:26,922 --> 00:13:29,949 So that can store the energy to be used 234 00:13:29,949 --> 00:13:31,866 when the cell is ready. 235 00:13:32,946 --> 00:13:34,542 And it's all a continuous cycle. 236 00:13:34,542 --> 00:13:36,967 Your cells use energy. 237 00:13:36,967 --> 00:13:40,378 You ingest food to gain energy. 238 00:13:40,378 --> 00:13:41,878 You make more ATP. 239 00:13:42,796 --> 00:13:44,713 The body uses more ATP. 240 00:13:46,152 --> 00:13:48,569 So a constant overall circle. 241 00:13:49,899 --> 00:13:53,471 You add energy, subtract it, add, subtract it. 242 00:13:53,471 --> 00:13:55,271 As long as your body's functional, 243 00:13:55,271 --> 00:13:57,562 you have to go through this on a daily, 244 00:13:57,562 --> 00:14:00,895 hourly, minute by minute basis actually.