Answer: B - People with two copies of the mutated gene have sickle-cell anemia. People with one copy of the mutated gene have both healthy and misshapen red blood cells and are carriers of the disease.
Explanation:
Co-dominance is when both the alleles of a gene in a heterozygote show. In the case of sickle cell anemia (since it is a co-dominant trait) even if the person only has one sickle cell allele, symptoms of sickle cell will still show up in that person. That's why the person in this example has both misshapen and healthy red blood cells.
Answer:
homologous structures.
Explanation:
If two organisms look very similar during their early stages of development, this is evidence that the organisms. evolved from a common ancestor.
Answer:
Explanation:
The electron-carrier proteins are arranged in the inner mitochondrial wall. A dehydrogenase enzyme (think of it as the first protein of the electron-transport chain) oxidises NADH2 (which is the reduced coenzyme NAD) and/or FADH2 (reduced coenzyme FAD). The energy from the oxidation process is used to pump hydrogen ions from the matrix to the inter-membrane space of the mitochondrion. Because of this, gradient of hydrogen ion concentration builds up across the inner mitochondrial membrane, which generates a potential difference across the membrane. The protons then flow back to the matrix through an enzyme called ATP synthase (also called ATPase). (This is called chemiosmosis because a chemical substance (H+) moves across a membrane, down the concentration gradient.) This releases energy needed for the ATP synthase to phosphorylate ADP, i.e. make ATP (chemical energy for use in the cell) from ADP and inorganic phosphate.
Note: Bolded things are important, everything else is just additional clarification in case you need it. This is the last major phase of cellular respiration. If you want a deeper insight into the process, I suggest you read a bit about glycolysis and Krebs cycle.
Answer: c. Air pollution
Explanation:
There was a heatwave in Europe during the early years of the 21st century that killed tens of thousands across the continent and thousands in France.
Air pollution was blamed for having made the situation worse because the pollutants in the air acted to prevent heat from escaping back into the atmosphere which led to increased heat on ground and therefore a heat wave.
<span>Answer: Biodiversity</span>
The suppression of forest fires causes a decrease in biodiversity because
some habitats require exposure to fire. Most ecosystems of savanna, chaparral
and coniferous forests have developed with fire as an essential contributor to habitat’s vigor
and regeneration.
Additionally, wildfire suppression eliminates plant species
in fire-affected environments that require fire to germinate, established, or to
reproduce. Also, animals that depend on these plants will be affected too.
