Introduction
All Chemical reactions, reproduction processes, cellular functioning, and general body development require energy for proper functioning. Deficiency in energy supply to body parts leads to death in all living organisms. Photosynthetic organisms utilize the sun as their main source of energy, through the conversion of solar energy to chemical energy. Other organisms (not photosynthetic) depend on the energy that is stored in photosynthetic organisms.
Metabolism comprises all chemical reactions that sustain living cells. It is divided into two: anabolism and catabolism (Ophardt, 2003, Para. 1, 2). Organisms use specific adaptive characteristics that are either behavioral or biological to adapt to their habitats. This paper will discuss different organisms’ cells and their adaptive characteristics about metabolism and respiration.
Cells
Cells are the building blocks of life. They help the organism absorb nutrients and convert the nutrients into energy. In addition, cells perform other specialized functions in the body that sustain organisms. There are two types of cells: prokaryotic and eukaryotic. Prokaryotic cells are found in single-celled organisms, whereas eukaryotic cells are found both in unicellular and multicellular organisms. (Cell, 2009, Para 1-7).
Bacteria’s Prokaryotic cells
Bacteria are single-celled microscopic organisms. These cells have neither a nucleus nor other organelles for example the mitochondria and chloroplasts. These organisms reproduce mostly asexually. They exhibit different metabolic traits hence defining their taxonomy.
Their metabolism is divided into nutritional groups depending on three factors: energy sources, electron donors, and the origin of carbon. The nutritional types are phototrophs, organography, and lithographs. Autotrophic microorganisms, obtain their carbon through fixation, Lithographs make use of inorganic electron donors whereas; organography uses primarily organic. Most respiratory bacteria utilize chemical compounds to make energy. The organisms achieve this by removing electrons from broken substrates and changing them into electron acceptors (Mcguigan, 2009, Para 1-6).
Bacteria have several structures that help them to adapt to their habitats. These structures are the plasma membrane, cell wall, capsule, ribosomes, nucleoid, pilus, and flagellum.
The cell wall
The Bacteria cell wall is made up of peptidoglycan. This gives the cell its shape and covers the cytoplasmic membrane. Peptidoglycan is made up of glucose derivatives: N-acetyl muramic acid and N-acetylglucosamine. In gram-positive bacteria, the cell wall is mostly made up of peptidoglycan. On the other hand, gram-negative bacteria have a complex cell wall (chemically), where peptidoglycan is minimal.
Fine-tuning of the biophysical conditions by the bacteria cell wall helps it to adapt to changing environments. For example, in cases where the lipid bilayer is high, some bacteria will produce lysine that will neutralize the effect. Many bacteria resist cationic antimicrobial peptides by minimizing the negative charge on their cell wall. The wall is very strong, hence adapted to respond to changes in osmotic pressure. In addition to protection, the cell wall also helps bacteria to resist disease attacks (Davidson, 2009, Para. 5, 6).
The flagellum
Motility assists bacteria to obtain nutrients. In addition, it helps bacteria to protect themselves from predators and dangerous chemicals. The flagella are hair-like structures found on either the body’s sides or the whole body. They are long and rotate to enable bacteria to move faster in all media. They have nucleoid and cyclic catabolite proteins that are activated to provide energy during motility. To respond to poor carbon sources, they activate their chemotaxis genes, hence enabling the move to favorable environments (Burgess & Mingzhu, 2007, p. 4451-4456)
Animal- eukaryotic cells
Animals are multicellular organisms. Their cells do not have a cell wall. All animals are motile, although some do not have muscles for movement. Animals’ bodies have skeletons that help in mobility, protection, and support. Their cells have many organelles that function differently. Some of these organelles are the lysosomes, mitochondria, centrioles, and ribosomes. Animals have diploid cells hence, the occurrence of chromosomes in homologous pairs.
Mitochondria
The mitochondria are elongated structures found in the cytoplasm. Their main function is to provide energy by converting nutrients. In addition to providing energy, it helps the body in cell differentiation. It has sections that perform different functions. Its parts include the inner and outer membrane, matrix, and cristae. They also have proteins that vary with species and tissues. It produces adenosine triphosphate through the conversion of nutrients. It further, converts pyruvate, sugars that are produced in the cytosol to energy. It achieves this through either aerobic or anaerobic respiration. They help also help to control the metabolic rate through muscles.
The mitochondria’s outer membrane is smooth but the inner membrane is highly folded forming the cristae. The crista is folded to increase the surface area for respiration. The outer membrane prevents the entry of big particles into the matrix; it has a protein called porin. The inner membrane is structured to only allow proteins that have correct molecules (Davidson-mitochondria, 2009, Para. 1-4).
Ribosomes
On the other hand, ribosomes help the body to translate DNA sequences into proteins. They are made up of ribonucleic acids and proteins. In addition, they have two components for effective working. Each of these components has a specified number of RNA. Ribosomes are created in the cytoplasm through “copying” of their genes called operons. They either are located in the cytosol or attached to the endoplasmic reticulum. They organize amino acids into polypeptide sequences, by “sticking” themselves on RNA molecules; which coins the required order of amino acids. The body can change the number of ribosomes depending on metabolism requirements; hence their adaptive mechanism (Rice &Harnett, 2009, Para 1-4).
Conclusion
In conclusion, the cell plays a very important function in an organism’s survival. These functions include molecule transport, reproduction, and energy production. The connections between these structures enhance an organism’s performance levels hence ultimate survival.
Reference List
Burgess, R. R., & Mingzhu, L. (2007). Adaptation in bacterial flagella and motility systems: from regulon members to ‘foraging’-like behavior in E. coli. Nucleic acids research 35(13), 4441–4452.
Davidson, W. M. (2009). Bacteria Cell Structure. English simple dissector. Web.
Mcguigan, B. (2009). Types of bacteria. Wisegeek. Web.
Ophardt, E. C. (2003). Metabolism and energy. Virtual chembook: Elmhurst College. Web.
Rice, D., Harnett, A. ribosomes. 2009. Web.
Science clarified. (2009). The cell.Admeg. Web.