1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
iren2701 [21]
3 years ago
11

Savannas do not exist in the United States because

Biology
2 answers:
Klio2033 [76]3 years ago
4 0
There are no true tropic climates
barxatty [35]3 years ago
3 0
Because there is not a true tropical climate in the United States
You might be interested in
If mrna codons are aug, ggu and cag, what three codons of trna will attach?
Artemon [7]

Source : Net

* it signals the start of translation  

* it codes for the incorporation of the amino acid methionine (Met) into the growing polypeptide chain  

The genetic code can be expressed as either RNA codons or DNA codons. RNA codons occur in messenger RNA (mRNA) and are the codons that are actually "read" during the synthesis of polypeptides (the process called translation). But each mRNA molecule acquires its sequence of nucleotides by transcription from the corresponding gene. Because DNA sequencing has become so rapid and because most genes are now being discovered at the level of DNA before they are discovered as mRNA or as a protein product, it is extremely useful to have a table of codons expressed as DNA. So here are both.  

Note that for each table, the left-hand column gives the first nucleotide of the codon, the 4 middle columns give the second nucleotide, and the last column gives the third nucleotide.  

The RNA Codons  

Second nucleotide U C A G  

U UUU Phenylalanine (Phe) UCU Serine (Ser) UAU Tyrosine (Tyr) UGU Cysteine (Cys) U  

UUC Phe UCC Ser UAC Tyr UGC Cys C  

UUA Leucine (Leu) UCA Ser UAA STOP UGA STOP A  

UUG Leu UCG Ser UAG STOP UGG Tryptophan (Trp) G  

C CUU Leucine (Leu) CCU Proline (Pro) CAU Histidine (His) CGU Arginine (Arg) U  

CUC Leu CCC Pro CAC His CGC Arg C  

CUA Leu CCA Pro CAA Glutamine (Gln) CGA Arg A  

CUG Leu CCG Pro CAG Gln CGG Arg G  

A AUU Isoleucine (Ile) ACU Threonine (Thr) AAU Asparagine (Asn) AGU Serine (Ser) U  

AUC Ile ACC Thr AAC Asn AGC Ser C  

AUA Ile ACA Thr AAA Lysine (Lys) AGA Arginine (Arg) A  

AUG Methionine (Met) or START ACG Thr AAG Lys AGG Arg G  

G GUU Valine Val GCU Alanine (Ala) GAU Aspartic acid (Asp) GGU Glycine (Gly) U  

GUC (Val) GCC Ala GAC Asp GGC Gly C  

GUA Val GCA Ala GAA Glutamic acid (Glu) GGA Gly A  

GUG Val GCG Ala GAG Glu GGG Gly G  

The DNA Codons  

These are the codons as they are read on the sense (5' to 3') strand of DNA. Except that the nucleotide thymidine (T) is found in place of uridine (U), they read the same as RNA codons. However, mRNA is actually synthesized using the antisense strand of DNA (3' to 5') as the template. [Discussion]  

This table could well be called the Rosetta Stone of life.  

The Genetic Code (DNA)  

TTT Phe TCT Ser TAT Tyr TGT Cys  

TTC Phe TCC Ser TAC Tyr TGC Cys  

TTA Leu TCA Ser TAA STOP TGA STOP  

TTG Leu TCG Ser TAG STOP TGG Trp  

CTT Leu CCT Pro CAT His CGT Arg  

CTC Leu CCC Pro CAC His CGC Arg  

CTA Leu CCA Pro CAA Gln CGA Arg  

CTG Leu CCG Pro CAG Gln CGG Arg  

ATT Ile ACT Thr AAT Asn AGT Ser  

ATC Ile ACC Thr AAC Asn AGC Ser  

ATA Ile ACA Thr AAA Lys AGA Arg  

ATG Met* ACG Thr AAG Lys AGG Arg  

GTT Val GCT Ala GAT Asp GGT Gly  

GTC Val GCC Ala GAC Asp GGC Gly  

GTA Val GCA Ala GAA Glu GGA Gly  

GTG Val GCG Ala GAG Glu GGG Gly  

*When within gene; at beginning of gene, ATG signals start of translation.  

Codon Bias  

All but two of the amino acids (Met and Trp) can be encoded by from 2 to 6 different codons. However, the genome of most organisms reveals that certain codons are preferred over others. In humans, for example, alanine is encoded by GCC four times as often as by GCG. Why should this be? The answer is uncertain but probably reflects a greater translation efficiency by the translation apparatus (e.g., ribosomes) for certain codons over their synonyms.  

Codon bias even extends to pairs of codons: wherever a human protein contains the amino acids Ala-Glu, the gene encoding those amino acids is seven times as likely to use the codons GCAGAG rather than the synonymous GCCGAA.  

Codon bias is exploited by the biotechnology industry to improve the yield of the desired product. The ability to manipulate codon bias may also usher in a era of safer vaccines. Link to a discussion.  

Exceptions to the Code  

The genetic code is almost universal. The same codons are assigned to the same amino acids and to the same START and STOP signals in the vast majority of genes in animals, plants, and microorganisms. However, some exceptions have been found. Most of these involve assigning one or two of the three STOP codons to an amino acid instead.  

Mitochondrial genes  

When mitochondrial mRNA from animals or microorganisms (but not from plants) is placed in a test tube with the cytosolic protein-synthesizing machinery (amino acids, enzymes, tRNAs, ribosomes) it fails to be translated into a protein.  

The reason: these mitochondria use UGA to encode tryptophan (Trp) rather than as a chain terminator. When translated by cytosolic machinery, synthesis stops where Trp should have been inserted.  

In addition, most  

* animal mitochondria use AUA for methionine not isoleucine and  

* all vertebrate mitochondria use AGA and AGG as chain terminators.  

* Yeast mitochondria assign all codons beginning with CU to threonine instead of leucine (which is still encoded by UUA and UUG as it is in cytosolic mRNA).

3 0
3 years ago
Which descriptions represent social consequences of sustainable land use?
Zina [86]

Answer:

II and III

Explanation:

Did the quiz : ()

6 0
2 years ago
Select all that apply.
andriy [413]

The <em>correct</em> answer is:

Penicillium

Aspergillus

The lesson states:

If you've ever heard of or taken penicillin to fight off an infection, you can thank a member of the imperfect fungi called penicillium. Some mold species of penicillium are also important in the flavoring and aging of cheese. Roquefort and Camembert cheese owe their distinctive flavors to these fungi. Aspergillus is an imperfect fungus that is found on decaying food. It also contributes to the production of organic acids like citric acid. <u>Both penicillium and aspergillus produce enzymes that are purified and used in various industrial compounds and in medicine.</u>

<u></u>

7 0
3 years ago
Assume that you have 1 mL of a solution of amylase (an enzyme) at a concentration of 15 mg protein/mL. Calculate the volume of d
lidiya [134]

Answer:

42,5 mL

Explanation:

We need to use the serial dilution formula beacuse we start with a stock concentrate solution and we need to prepare a new less concentrated one.

DF=\frac{Vi}{Vf}

<u>DF in the dilution factor, Vi is the initial volume and Vf is the final volume.</u>

The first step is to have the same measurment unit so we need to convert 345 µg to mg.

we know that 1 µg equals 0,001 g, hence:

345 µg = 0,345 mg

now the final volume is 0,345 mg  protein/ mL and the inital volume is 15mg protein/mL, both of them are in the same unit so we can use the formula

DF= \frac{15mg protein/mL}{0.345mg protein/mL}

DF= 43,5 mg protein/ mL

Now since the question said that we already have 1.0mL of the amylase stock solution we need to subtract that 1.0mL to the 43,5 mg protein/mL

43,5mL-1,0mL = 42,5 mL

So, we need 42,5 mL of diluting buffer if we want a final concentration of 345 µg protein/mL (0.345 mg protein/mL)

8 0
3 years ago
Due to a mistake during meiosis, a plant species produces gametes that are diploid instead of haploid. The gametes now have twic
valkas [14]

Answer:

b. Sympatric autopolyploidy

Explanation:

Sympatric speciation will occurs when a new species when two groups from the same ancestral population evolve without any geographical separation.

Autopolyploidy will appear when an individual possess more that two sets of chromosomes both from the same parental species

Therefore, since a new species was formed as a result of autopolyploidy. The type of speciation that occurred was Sympatric speciation.

3 0
3 years ago
Other questions:
  • Which arrows represent carbon dioxide entering the atmosphere by cellular respiration?
    6·1 answer
  • The external similarity of insect wings and bird wings is an example of
    10·1 answer
  • Imagine a person is in a car accident and suffers a sever physical injury. The
    9·1 answer
  • 1.where does the energy required the process of cellular respiration come from?
    10·1 answer
  • What conditions make for a violent volcanic eruption?
    11·2 answers
  • How is the size of the pupil regulated
    14·2 answers
  • Explain the difference between physical and chemical properties. Provide an example of each.
    12·1 answer
  • When mosquitoes are very abundant, purple martins flock to the area and specialize on them. When mosquito populations are not la
    5·1 answer
  • Scientist who studies the plant life in an environment
    14·2 answers
  • What makes one DNA molecule different from another?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!