Answer the following question given this paragraph: All chemical reactions, even exothermic reactions, need a certain amount of energy to get started. This energy is called activation energy . For example, activation energy is needed to start a car. Turning the key causes a spark that activates the burning of gasoline in the engine. The combustion of gas won't occur without the spark of energy to begin the reaction. Q: The energy a chemical reaction needs to get started is called what kind of energy? Choices: - function - conduction - fusion - activation A:
activation
Answer the following question given this paragraph: 28.3 Fetal Development The fetal period lasts from the ninth week of development until birth. During this period, male and female gonads differentiate. The fetal circulatory system becomes much more specialized and efficient than its embryonic counterpart. It includes three shuntsthe ductus venosus, the foramen ovale, and the ductus arteriosusthat enable it to bypass the semifunctional liver and pulmonary circuit until after childbirth. The brain continues to grow and its structures differentiate. Facial features develop, the body elongates, and the skeleton ossifies. In the womb, the developing fetus moves, blinks, practices sucking, and circulates amniotic fluid. The fetus grows from an embryo measuring approximately 3.3 cm (1.3 in) and weighing 7 g (0.25 oz) to an infant measuring approximately 51 cm (20 in) and weighing an average of approximately 3.4 kg (7.5 lbs). Embryonic organ structures that were primitive and nonfunctional develop to the point that the newborn can survive in the outside world. Q: In humans, what period lasts from the ninth week of development until birth? Choices: - third trimester - plasma period - development period - fetal period A:
fetal period
Q: Answer the following question given this paragraph: A combustion engine is a complex machine that burns fuel to produce thermal energy and then uses the energy to do work. Two basic types of combustion engines are external and internal combustion engines. Q: What are the two basic types of combustion engines? Choices: - gas and steam - spark and steam - diesel and internal combustion - external and internal combustion engines A:
A: external and internal combustion engines
Question: Answer the following question given this paragraph: Phenotypes and Genotypes Two alleles for a given gene in a diploid organism are expressed and interact to produce physical characteristics. The observable traits expressed by an organism are referred to as its phenotype. An organism's underlying genetic makeup, consisting of both the physically visible and the non-expressed alleles, is called its genotype. Mendel's hybridization experiments demonstrate the difference between phenotype and genotype. For example, the phenotypes that Mendel observed in his crosses between pea plants with differing traits are connected to the diploid genotypes of the plants in the P, F1, and F2 generations. We will use a second trait that Mendel investigated, seed color, as an example. Seed color is governed by a single gene with two alleles. The yellow-seed allele is dominant and the green-seed allele is recessive. When true-breeding plants were cross-fertilized, in which one parent had yellow seeds and one had green seeds, all of the F1 hybrid offspring had yellow seeds. That is, the hybrid offspring were phenotypically identical to the true-breeding parent with yellow seeds. However, we know that the allele donated by the parent with green seeds was not simply lost because it reappeared in some of the F2 offspring (Figure 8.5). Therefore, the F1 plants must have been genotypically different from the parent with yellow seeds. The P plants that Mendel used in his experiments were each homozygous for the trait he was studying. Diploid organisms that are homozygous for a gene have two identical alleles, one on each of their homologous chromosomes. The genotype is often written as YY or yy, for which each letter represents one of the two alleles in the genotype. The dominant allele is capitalized and the recessive allele is lower case. The letter used for the gene (seed color in this case) is usually related to the dominant trait (yellow allele, in this case, or "Y"). Mendel's parental pea plants always bred true because both. Q: What is the term for an organism's underlying genetic makeup, consisting of both the physically visible and the non-expressed alleles? Choices: - divergency - trait map - phenotype - genotype A:
Answer: genotype
*Question*
Answer the following question given this paragraph: Found as a pure element in nature; oxides decompose with heating. Q: What causes oxides to decompose? Choices: - humidity - acidity - precipitation - heat A:
**Answer**
heat
*Question*
Answer the following question given this paragraph: Imagine now that you have a second cup with 100ml of water, and you add 45 grams of table sugar to the water. Just like the first cup, the sugar is the solute, and the water is the solvent. But now you have two mixtures of different solute concentrations. In comparing two solutions of unequal solute concentration, the solution with the higher solute concentration is hypertonic , and the solution with the lower solute concentration is hypotonic . Solutions of equal solute concentration are isotonic . The first sugar solution is hypotonic to the second solution. The second sugar solution is hypertonic to the first. Q: In comparing two solutions of unequal solute concentration, the solution with the higher solute concentration is called what? Choices: - acetic - hypothermic - hydrophilic - hypertonic A:
**Answer**
hypertonic