Answer:
These include temporal isolation, ecological isolation, behavioral isolation, and mechanical isolation. Post-zygotic barriers: barriers that come into play after two species have mated. These include genetic incompatibility, zygotic mortality, hybrid inviability, hybrid sterility, and hybrid breakdown.
Explanation:
1) B
(I'm not so sure of this one) All of the other options have a steady impact on population regardless of the density of organisms except competition
2) D
Increased carbon dioxide levels would not hinder plant growth, and tsunamis aren't really linked to carbon dioxide levels. Increased carbon dioxide is unlikely to lower the air temperature so only D is left.
3) A
4) Three properties of water that allow it to sustain life are that it is adhesive, it is a good solvent, and cohesion. Adhesion is important in situations such as water travelling up xylem tubes in plants so that the water is not pulled down by gravity and can reach parts of the plant that need water. Cohesion allows the water being pulled up the xylem to stay together and for water molecules to be pulled when a neighbouring one is moved. Water being a good solvent allows inorganic minerals to be taken with water through vascular tissue, such as in the previous example.
Answer:
fills container, no visible shape, flows
False there may be two or more dependent variables in a well designed experiment
Answer: 25% of the offsprings will be heterozygous for both traits
Explanation: A cross between BbFf and bbff will yield 16 offsprings with four different possible genotypes: BbFf, Bbff, bbFf, and bbff. Only BbFf is the genotype that is heterozygous for both traits, and there are four offsprings with BbFf genotype.
Therefore the percentage of the offsprings that are heterozygous for both traits is 4/16 x 100 = 25%
See the punnett square for the details of the dibybrid cross
