#31 - Sep 2019 - Garden Stuff - © Sandy Lang - slang@xtra.co.nz
GENES August/September: Early spring. Temperatures rising. Pruning done. Plant new trees/shrubs now.
Genes: Plants and animals. There’s less difference than you might think. •About 60% of your genes are similar to a banana’s, 90% to your cat’s and 99.9% to mine - that's really scary...! •It’s only 0.1% of our 25,000 different genes that tell us apart: sex, eye-colour, personality, health, height, blood-type… •A few of these characteristics are determined by a single gene (freckles) but most involve multiple genes. •Our 25,000 different genes each contain the code to make one protein, so we have about 25,000 different proteins.
Proteins: Indeed, we’re largely made of proteins. •Some are structural (keratin – hair), others are functional (lipase – digests fat). •A protein is a very long chain of 1,000 to 1,000,000 amino acids. •There are 20 different amino acids (glutamine, serine and 18 others). •The properties of a protein depend on the exact sequence of these 20 amino acids along the chain – get one amino acid wrong, and the protein may not work. •The precise amino acid sequence of each of our proteins is coded in our DNA.
DNA: Each cell contains a nucleus, and each nucleus contains the full genetic code for all our proteins. •This code is contained in a 2 m length of DNA - all scrunched up in a tiny ball. •Think of DNA as a spiral ladder with 3,000,000,000 rungs - that’s as many rungs, as the number of millimetres of road between Auckland and Bluff, and back.
Bases: There are four different sorts of rungs (bases) - Adenine, Thymine, Guanine and Cytosine. •These four bases appear in an exact sequence along the 3,000,000,000-rung DNA ladder. •Writing just their initial letters, a close-up of a minute part of the DNA ladder might read – ACATGACAAGTCGCGGACAACTCCAGUAATTGT…
Code: There are 64 different ways of writing these four letters into three-letter 'words' (making 64 different words). •Many of these words share the same meaning, so CAA and CAG both code for the amino acid glutamine, and AGC and AGT both code for serine (in all, 64 words code for 20 amino acids).
mRNA: To make a particular protein, the cell first makes a copy of the corresponding section of DNA code (gene). This gene copy is called mRNA. •The mRNA is then read by a tiny machine (a ribosome) which constructs the protein chain according to the three-letter word codes, one amino acid at a time.___________________________________
GENES August/September: Early spring. Temperatures rising. Pruning done. Plant new trees/shrubs now.
Genes: Plants and animals. There’s less difference than you might think. •About 60% of your genes are similar to a banana’s, 90% to your cat’s and 99.9% to mine - that's really scary...! •It’s only 0.1% of our 25,000 different genes that tell us apart: sex, eye-colour, personality, health, height, blood-type… •A few of these characteristics are determined by a single gene (freckles) but most involve multiple genes. •Our 25,000 different genes each contain the code to make one protein, so we have about 25,000 different proteins.
Proteins: Indeed, we’re largely made of proteins. •Some are structural (keratin – hair), others are functional (lipase – digests fat). •A protein is a very long chain of 1,000 to 1,000,000 amino acids. •There are 20 different amino acids (glutamine, serine and 18 others). •The properties of a protein depend on the exact sequence of these 20 amino acids along the chain – get one amino acid wrong, and the protein may not work. •The precise amino acid sequence of each of our proteins is coded in our DNA.
DNA: Each cell contains a nucleus, and each nucleus contains the full genetic code for all our proteins. •This code is contained in a 2 m length of DNA - all scrunched up in a tiny ball. •Think of DNA as a spiral ladder with 3,000,000,000 rungs - that’s as many rungs, as the number of millimetres of road between Auckland and Bluff, and back.
Bases: There are four different sorts of rungs (bases) - Adenine, Thymine, Guanine and Cytosine. •These four bases appear in an exact sequence along the 3,000,000,000-rung DNA ladder. •Writing just their initial letters, a close-up of a minute part of the DNA ladder might read – ACATGACAAGTCGCGGACAACTCCAGUAATTGT…
Code: There are 64 different ways of writing these four letters into three-letter 'words' (making 64 different words). •Many of these words share the same meaning, so CAA and CAG both code for the amino acid glutamine, and AGC and AGT both code for serine (in all, 64 words code for 20 amino acids).
mRNA: To make a particular protein, the cell first makes a copy of the corresponding section of DNA code (gene). This gene copy is called mRNA. •The mRNA is then read by a tiny machine (a ribosome) which constructs the protein chain according to the three-letter word codes, one amino acid at a time.___________________________________