Insects and millipedes were among the very first terrestrial animals. hypothesize what characteristics of their aquatic ancestors among animals related to crustaceans (think lobsters, crabs, etc.) may have acted as a preadaptation that could be co-opted for use in terrestrial habitats.

Preadaptations like tegument and body segmentation could have been used by insects and millipedes to survive in terrestrial habitats.

Explanation:

As crustaceans, millipedes and insects have a protective, hard tegument, which surface is frequently smooth. Some groups can also present spines, bristles, or tubercles.  The tegument protects the animals against harmful stimuli of different nature, such as mechanic, thermal, chemical, etc. It is also an effective barrier against pathogen microorganisms and excessive dehydration. In groups like crustaceans and insects, as the external layer gets hard, the tegument constitutes an important support organ. It is composed of a simple, cubic epithelium called hypodermis, and secretes exoskeleton, which is composed of chitin and can also be shaped by calcareous impregnations. Chitin is an impermeable, light y hard substance, that allows life on land without dehydration.   Segmentation (repetition of identical anatomical units) is another characteristic in these groups that have helped to domain terrestrial habitats. It seems like segmentation is highly advantageous from an evolution point of view because it is much easier to adapt each segment separately to environmental pressures, responding to different necessities, than adapting the whole body to it, developing a new organ for each necessity. Also, it is a strategy to defend themselves from predators by rolling up.

q: compare the parts of a cell and the cell as a whole to another common nonliving system (i.e., a car, a city,

a:

comparing this to the inside of a food building/company.

all cells are surrounded by a plasma membrane, which protects the cell from its environment, keeping toxic substances out of the cell. it regulates which molecules are allowed to enter and exit the cell.

regulates all cell activity such as cellular metabolism, and growth in addition to storing and maintaining the cell's dna for transcription and replication. determines what proteins to make.

contains the organelles; site of most cell activity

the place where ribosomes do their working activity.

builds the proteins.

prepares proteins for use or export.

responsible for breaking down and absorbing materials taken in by the cell.

maintains cell shape.

transforms one form of energy into another.

transcription is a process in which information is rewritten. it is something our cells must do, in a more specialized and narrowly defined way. in biology, transcription is the process of copying out the dna sequence of a gene in the similar alphabet of rna. it needs to happen in the nucleus because that's where the dna is. dna is always inside the nucleus unless the cell is dividing.

transcription is the first step in gene expression, which involves copying a gene's dna sequence to make an rna molecule. transcription is performed by rna polymerases. it has three stages: initiation, elongation, and termination. rna molecules must be processed after transcription in eukaryotes.

explanation:

long version:

the protein synthesis consists two processes which are, transcription and translation. transcription takes place in the nucleus. it uses dna as a template to make an rna molecule. rna then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. transcription is the first part of the central dogma of molecular biology: dna → rna. it is the transfer of genetic instructions in dna to messenger rna (mrna). during transcription, a strand of mrna is made that is complementary to a strand of dna.  

these three stages are:

  initiation: in which   is the beginning of transcription.occuring when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

    elongation: in which is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

    termination: in which is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.