Some methods of determining the size of population are direct and indirect observations, sampling, and mark-and-recapture studies
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Sampling - Done by counting the animals in a small area and then estimating how many are in the larger area. You go out and take samples from different places so you can take the average. In most cases, it is not possible to count every member of a population so an estimate is made.
Mark and recapture - Another estimating method is a technique called "mark and recapture." This technique gets its name because some animals are first captured, marked, and released into the environment. Then another group of animals is captured. The number of marked animals in this second group indicates the population size.
Indirect observation - The members of a population may be small or hard to find. It may be easier to observe their tracks or other signs rather than the organisms themselves.
Direct observation - The most obvious way to determine the size of a population is to count, one by one.
Answer:
Many species would eventually die off because they lack a food source.
Explanation:
<u>Photosynthesis can be defined simply as the biological process of using light to synthesize food (in the form of glucose). It is a process that takes place in plants and involves the synthesis of sugar using inorganic products such as water and carbon dioxide.</u>

The process consists of two stages namely;
- Light reaction
- Light independent reaction.
The products from the light reaction are utilized in the light-independent reaction.
<em>Hence, without light energy, the process of photosynthesis cannot proceed and plants will not be able to manufacture foods. Without foods, many plant species would die off. </em>
Limiting nutrient<span>. The concept of a </span>limiting nutrient<span> is essential to understanding the </span>biological<span> processes. The </span>nutrient<span> in short supply relative to the others will be exhausted first and will thus </span>limit<span> cellular growth</span>
1.What is the probability that a sperm from the father will contain the PKU allele?
Probability = ½
2.What is the probability that an egg from the mother will contain the PKU allele?
Probability = ½
3.What is the probability that their next child will have PKU?
Probability = ¼ (because each parent has ½ chance ½ X ½ = ¼)
4.What is the probability that their next child will be heterozygous for the PKU gene?
Probability = ½ (because each parent has ½ chance of donating the ‘P’ allele and ½ chance of donating the ‘p’ allele (½ x ½) + (½ x ½) = ½