Answer:
OH, H2O2 and O−2
Explanation:
Reactive oxygen species (ROS) can be defined as highly reactive chemical compounds formed from molecular oxygen (O2). ROS are generated as a normal product of cellular metabolism, and also as a response to different environmental/internal cellular stimuli (e.g., cytokines, xenobiotics, pathogenic invasion). For example, hydroxyl radicals (·OH) are a type of ROS generated in the mitochondria which are capable of inducing oxidative stress in different cells and also trigger chronic inflammation. Moreover, hydrogen peroxide (H2O2) molecules represent another type of ROS which are produced during the stereoselective deamination of amino acids, i.e., the building blocks of proteins. These molecules (H2O2) exhibit toxic effects on the cell (e.g., DNA damage). Finally, singlet oxygen (1O2) is an excited state of molecular oxygen (O2) that is generated during photosynthesis in the photosystem II (PSII) of chloroplasts.
-DNA is double stranded,RNA is one stranded
-DNA contains the following nitrogenous bases:Adeninde Guanine Timine Citozine while RNA contains Adeninde Guanine Citozine and Uracil
-DNA function is to contain the information for manufacturing proteins while there are many types of RNA with whole different jobs for example:messanger RNA(mRNA) it coppies a sequence from the DNA strand and takes it to the ribosome in order to be translated as the order for placing aminoacids in the polypeptide strand;transport RNA(tRNA) it is a short RNA strand containing up to 100 nucleotides it takes aminoacids to the ribosome so the polypeptides strand can start to be manufatured from aminoacids in an order inscripted in the mRNA.
Answer:
The correct answer is - option B. They are small because they lack a nucleus.
Explanation:
Red blood cells or erythrocytes are specialized cell that produce in bone marrow and have specific role such as carrying oxygen from lungs to deliver it to the various organs and carry out carbon dioxide.
In mammals these cells lack cell organelles such as nucleus and mitochondria, a major factor that determined its smaller size. The size of RBC are move through narrow vessels throughout a organism because of its specific size and shape that provide it space for hemoglobin and allow to be flexible and bend to move through narrow vessels.
Thus, the correct answer is : option B. They are small because they lack a nucleus.
Photosynthesis, respiration and combustion.