The Rh factor identifies the presence of the rhesus protein in blood. The Rh factor can be represented by a + or – sign. It is important to know the Rh factor because just like how the antigens on the blood must be compatible, the rhesus protein in blood must also be compatible. If a person has Rh+ blood they can receive blood. If a person has Rh- blood they can receive blood.

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.

explanation:

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.

organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.

not only is it colder, it also becomes darker, less salty, and more dense.