Question 27

elements that are gases, or are brittle solids, and are poor conductors at room temperature are

a)metals

b)nonmetals

c)metalloids

d)isotopes

Elements that are gases, or are brittle solids, and are poor conductors at room temperature are nonmetals

Explanation:

Elements that are usually gases or solids and are poor conductors at room temperature.

Metals not an option, because they aren't gasses. Most metals have a characteristic lustre and are good conductors of heat and electricity, at room temperature.

Metalloids are unique because they have properties of both metals and non-metals. But, most metalloids are poor conductors of heat and electricity. Metalloids aren't an option either.

Every element has isotopes. They can be gasses, solids,.. Can be good or bad conductors. Isotopes isn't an option either.

Solid nonmetals are not malleable or ductile, but brittle or powdery. Nonmetals are poor conductors of heat and electricity, because electrons are not free to move.

Elements that are gases, or are brittle solids, and are poor conductors at room temperature are nonmetals

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: