Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. Recent gene knockout approaches in mice have revealed that many factors previously considered important for fertilization are largely dispensable, or if they are essential, they have an unexpected function. These results indicate that what has been observed in in vitro fertilization (IVF) differs significantly from what occurs during “physiological” fertilization. This Review focuses on the advantages of studying fertilization using gene-manipulated animals and highlights an emerging molecular mechanism of mammalian fertilization.
The cell membrane is made out of lipid bilayers and energy. They also have on the outside for identifying
Hairpin like structures are formed in both DNA and RNA but are common in RNA than in DNA. This is because DNA can be double stranded or single stranded while RNA is generally single stranded structure that can be double stranded only when it forms a hair pin like structure.
The features of hairpin structure in RNA are as follows:
1. This structure is a building block of many secondary structures of RNA.
2. The termination sequence during transcription also forms a hairpin loop like structure.
3. tRNA also forms a hairpin loop like structure and helps in the process of translation.
Answer:
As competition increases and resources become increasingly scarce, populations reach the carrying capacity (K) of their environment, causing their growth rate to slow nearly to zero. This produces an S-shaped curve of population growth known as the logistic curve (right).
Explanation:
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