Answer:
a. positive; negative
Explanation:
Transcription is the process of forming an RNA molecule from a DNA template molecule. In this process, the strands of DNA separate and one serves as a template for RNA, while the other is inactive. At the end of the transcript, the tapes that have been split back together again.
The transcription process is divided into three steps: initiation, stretching and termination
During the stretching phase, transcription chain elongation occurs. In this phase the enzyme called RNA polymerase starts to move through the DNA molecule, unwinding its helix and producing an increasingly lengthened RNA molecule. The already transcribed DNA is rewound almost immediately, recomposing its double helix. This process is called the elongation phase.
During this process, it is believed that positive supercoils are generated ahead of the transcription bubble and and the negative supercoils behind it.
Answer:
There are from 200-500 million alveoli (mean diameter = 200 micrometers) in adult human lungs
Explanation:
The epithelial cells of the alveolar septum are markedly thinned and the capillary network immediately beneath the epithelium is the richest in the body.hope this helps you :)
Answer: The impact of the colliding plates can cause the edges of one or both plates to buckle up into a mountain ranges or one of the plates may bend down into a deep seafloor trench.
Explanation: A chain of volcanoes often forms parallel to convergent plate boundaries and powerful earthquakes are common along these boundaries.
Answer:
Fermentation is a chemical reaction that takes place in the cytoplasm and occurs when oxygen is low or absent. Byproducts of fermentation may include lactic acid or ethanol. Fermentation yields less ATP than the electron transport chain.
Explanation:
Fermentation is a chemical reaction that occurs under anaerobic or low-oxygen condition whereby the NADH produced during glycolysis is oxidized to NAD⁺ with the production of lactic acid as well as other products such as ethanol.
Since oxygen is lacking, pyruvate and NADH produced in glycolysis cannot be oxidized. In order to produce energy in the form of ATP for the cells and tissues,the NAD⁺ is regenerated from NADH by the reduction of pyruvate to lactic acid by the enzyme lactate dehydrogenase. In some other organisms such as yeast and microorganisms, pyruvate is converted to ethanol and carbon dioxide.
The net production of ATP in fermentation process is 2 molecules of ATp much lesser than that produced in aerobic respiration.