Explanation:
Fertilization, pictured in Figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. The egg and sperm each contain one set of chromosomes. To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. In mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. When a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. In placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in Figure 24.23b. The fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. The nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.
Answer:
The correct answer is 4. Plateaus.
Explanation:
A plateau is a relatively flat, relatively high-lying part of the earth's surface that is wholly or almost wholly bounded by steeply sloping terrains. There is a pronounced slope on at least one side. The original flat area has mostly risen vertically as a whole due to geological factors. It may possibly have been cut by rivers, giving the impression of a hill or mountain landscape, but this is not it.
Placental. it provide oxygen and nutrients to fetus. whilst removing carbon dioxide and other waste products
Answer:
One big reason we have water in our bodies is that it helps gives cells their structure, she said. It keeps cells a little plump. It also helps make different chemical reactions cells need to do their jobs. Water is also in charge of moving things around the cell to keep it working.
