A) Biological, physical, and chemical.
b) Physical: sediment radioactive material and heat.
c) Chemical: organic/inorganic: heavy metals, nutrients & pesticides.
Answer:
adaptations (based on natural selection)
Answer:
C. Sprout every year, year after year
Explanation:
The perennial plants are the plants that live for more then two years, thous some may argue that they are plants that live more then three years. Whichever the case, they are not short-lived plants, but are capable of surviving for numerous years, unlike the annuals and biennials. Theoretically, the shrubs and trees would fall into this category, but they are classified separately, and this term is not used for them, but for smaller plants that do not have or have very little woody parts. These plants tend to sprout every year, and even though they seemingly die in the autumn, their roots are alive, and they emerge and grow again in the spring, sprouting again. That process repeats itself for numerous years.
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.
Explanation:
charles darwin proposed thoery of natural selection.he had collected imnumerable specimens of plant and animals.he published concept survival of fittest. while explaining he says that There is always competition for food.only those organism survive which shows adptations in various reasons. it thoery of natural selection.
There are some objections,
1. natural selection is not only factor responsible for evolution.
2. darwin did not mention uesful and useless modifications.
3. There is no explanation about slow and abrupt changes
