Answer:
Improving drainage in the cities by ensuring that drainage channels are large enough to handle flood waters and that they are never blocked. Clogged drainages impede flow of water resulting to a rise in water levels in the city.
Ensure proper enforcement of laws that ensure that people do not settle on wetlands and riparian land. Wetlands are natural drainages for water and settling on them is akin to blocking drainages in a built environment.
Constructing flood gates and flood walls to redirect floodwaters away from populated areas. This is especially implemented in built environments that are in low-lying lands and prone to flooding.
Answer:
Positively charged ions
Explanation:
Histones are a group of proteins with a N-terminal end of an amino acid, that binds to the DNA in the nucleus helping it to condense into Chromatin. DNA wraps around a core of proteins to initially form the NUCLEOSO ME structure, which is the basic subunit of Chromatin. Each nucleosome is made up of DNA coiled around two copies (2) of proteins- H2A, H2B, H3 and H4, to form a set of eight proteins called histone octamer.
Due to the phosphate group (PO4-) embedded in the DNA molecule, they assume a negative charge. The positively charged ions of the N(C) terminal end of histones which arise from the amino acid group they contain allows it to bind tightly to negatively charged DNA i.e. the more positively and negatively charged the histone and DNA are respectively, the tighter the binding.
Due to this property, the proteins that binds to DNA in E.coli, should possess a positive charge in similarity to histones in eukaryotes.
Answer:
D) Transport of sodium ions down their electrochemical gradient facilitates the transport of glucose against its concentration gradient.
Explanation:
Active transport refers to the movement of molecules across biological membranes against a concentration gradient. Active transport can be divided into 1-primary active transport, which requires energy from the hydrolysis of adenosine triphosphate (ATP); and 2-secondary active transport, which requires an electrochemical gradient generated by pumping ions in/out of the cell. The case above described represent a type of secondary transport active because the movement of sodium (Na) ions is used as energy source to move glucose molecules against their concentration gradient.
Answer:
The stages of fertilization can be divided into four processes:
1) sperm preparation,
2) sperm-egg recognition and binding,
3) sperm-egg fusion and
4) fusion of sperm and egg pronuclei and activation of the zygote.
