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Leona [35]
4 years ago
12

People with Down syndrome usually have ______ of the 21st chromosome.

Biology
2 answers:
Ivahew [28]4 years ago
7 0
People with Down syndrome usually have trisomy of the 21st chromosome.
Elena-2011 [213]4 years ago
6 0
It is caused by a trisomy in the 21st chromosome 
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A total of _____ amino acids compose the majority of protein in living things and nine are _____ to human
Delicious77 [7]

Most proteins in living organisms are composed of 40 amino acid residues in total, and nine of those are crucial for human health.

Which majority of amino acids make up proteins in living things?

  • Only twenty different amino acids, each with a distinct side chain, make up proteins. Different chemistries can be found in the side chains of amino acids. The majority of amino acids contain side chains that are nonpolar.
  • There are nine essential amino acids:
  1. tryptophan
  2. valine
  3. isoleucine
  4. leucine
  5. lysine
  6. methionine
  7. phenylalanine
  8. threonine
  9. methionine

What Constitutes Proteins?

  • Amino acids are the basic units of proteins. They are tiny chemical compounds with an alpha (central) carbon coupled to an amino group, a carboxylic acid group, hydrogens, and a changeable element known as a side chain.
  • A protein is made up of a lengthy chain of amino acids that are connected by peptide bonds. The biological process that links the carboxyl unit of one amino acid towards the amino group of a nearby amino acid results in the extraction of a water molecule, forming peptide bonds. The main structure of a protein is thought to be its linear amino acid sequence.

Learn more about amino acids here:

brainly.com/question/11843803

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8 0
1 year ago
Which Matt it is most likely used to that by what happened before the start of the Paleozoic era
BaLLatris [955]

The Paleozoic Era ended with the largest extinction event in the history of Earth, the Permian–Triassic extinction event. The effects of this catastrophe were so devastating that it took life on land 30 million years into the Mesozoic Era to recover

7 0
3 years ago
Describe the actual and relative sizes of a virus, a bacterium, and a plant or animal cell.
anzhelika [568]

Answer :

The animals are categorized into 2 groups - eukaryotes and prokaryotes. The microbes like bacteria are coming under prokaryotes. They are unicellular organisms and without a true nucleus.

Viruses are the connecting link between the living and non - living. They are smaller than bacteria. The microbes less than 100 micrometer can't be seen by the naked eye. They can only visible under a microscope.

Viruses like polio, flu virus sizes are 10nm. But some of the viruses are also less than 10nm. The size of bacteria is 1 micrometer. The viruses are 10 times smaller than the bacteria.

The eukaryotic organisms are more advanced and multicellular. Their cell size is larger than bacteria and viruses. The red blood cells under the light microscope are 8 micrometers. The typical animal cells like sperm are 60 micrometers and a skin cell is 30 micrometers. The plant cell for example pollen is 90 micrometers.

The eukaryotic cells sizes are more than prokaryotes like bacteria.

3 0
4 years ago
Which aspects of cell structure best reveal evolutionary unity? what are some examples of specialized mods?
Crazy boy [7]
<span> 1. The genetic material is a good evidence of evolution because it's been conserved through time but with some slight differences.
Another important aspect is the </span><span>mitochondria.</span><span> The mitochondria resulted from a symbiotic relationship between bacteria and pre-eukaryotes. Explaining why the </span><span>mitochondria looks like a bacteria and has </span><span>bacterial DNA. 

2.  specialized cellular modifications:

There are cellular modifications happening in multicellular organisms. That means, they have different types of cells, with different functions and will express different characteristics. For example:
- </span><span>Nerve cells have  dendrites  which is important to receive the electrical signal from another neuron, other cells don't have that.
- Sperm cells have a tail ( </span><span><span><span>flagellum) in order to swim through the vagina and no other cell has that.
</span> </span></span>
5 0
3 years ago
What is ethology?
Andrej [43]
A. The study of animal behavior
5 0
3 years ago
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