With sexual reproduction a sperm coming from the male must unite with the female egg. Both are needed for this kind of reproduction, and an offspring CAN'T be formed without both. Unlike asexual reproduction, the offspring of a mammal reproducing sexually is DIFFERENT from both parents, since the offspring is a combination of both the mother and the father.
An easy to remember example I use when thinking about what sexual reproduction is:
the formation of a human child. A mother with her egg and the father with the sperm is BOTH needed. If you think about siblings that come from the same parents (and therefore same gene pool) they are not all exactly identical to each other. Although they may have similar features, they look different and are NOT genetically identical
Therefor for your question the answer is D.
Hope this helped!
Basically structure of DNA is very important in the process of replication.
DNA molecules have antiparallel structure i.e. the two strands of the halix run in opposite directions of one another. Each strand has 5 prime end and 3 prime end. Solving the structure of DNA unlocked the door to understanding many of the function of DNA, such as how it copied and how the information it carries can be used to produce protein.
Answer:
DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code
Explanation:
Answer:
All the given statements are correct except b.
Antimicrobial resistance (AMR) refers to the ability of a microorganism to grow in the presence of drug or a chemical that would normally limit its growth or kill it.
It makes it difficult for the existing drugs to eliminate the infection as they become less effective against the microbe.
There are five major mechanisms by which a microbe attains resistance against antimicrobial chemical or drug:
- Drug modification or inactivation: A microbial enzyme inactivates the antimicrobial agent. For example, few bacteria produce β-lactamases which provide multi-resistance against β-lactam antibiotics such as penicillin, cephalosporin etc.
- Alteration or modification of target site: An altered target site prevents the antimicrobial agent from binding to its target. For example, alteration of penicillin binding protein (PBP) in Methicillin-resistant <em>Staphylococcus aureus </em>(MRSA).
- Alteration of metabolic pathway: The microbe uses an alternative pathway to circumvent the blocked pathway. For example, sulfonamides-resistant bacteria started using preformed folic acid in place of para-aminobenzoic acid (PABA).
- Decreased drug accumulation: Microbial efflux pumps remove the antimicrobial agent (before it could do any damage) by pumping it out of the cell.
- Decrease in cell permeability: The permeability of the microbial envelope to the antimicrobial agent is decreased
Answer:
The intercalated cells in the distal convoluted tubule of a nephron can cause and increase or decrease in body pH.
Explanation:
The renal collecting duct is the nephron segment where the final urine content of acid equivalents and inorganic ions are determined.
Two types of cells regulate the acid-base and volume homeostasis.
Intercalated cells, which express acid-base transporters and vacuolar H+-ATPase, maintain an apropriate acid-base balance and principal cells that express the epithelial sodium channel ENaC and aquaporin 2, regulate electrolyte reabsorption.
Filtered bicarbonate is predominantly reabsorbed from the proximal convoluted tubule about 80% and the remaining bicarbonate is reabsorbed from the thick ascending limb of the loop of Henle, the distal nephron, specifically the distal convoluted tubule & the connecting tubule, and finally the cortical and both the outer and inner medullary collecting duct.
Intercalated cells are enriched in mitochondria, and express proteins involved in transport of proton equivalents such as vacuolar H+-ATPase, carbonic anhydrase II and bicarbonate transporters. There are two types of intercalated cells Type-A and Type-B.
