Answer:
e. All of the above are considered species under at least one species concept.
Explanation:
All of the abovementioned conditions satisfy at least one condition of species definition. Further arguments are given below to support each statement,
a. A species is the <u>monophyletic group</u> of individuals who has a <u>common ancestor</u> which could be <u>distinguished from the closest phylogenetic relative</u> based on <u>conserved genes</u> (16S in bacteria and 18S in eukaryotes). In the statement above, beetles satisfy this condition.
b. A species is the group of individuals that are capable of <u>exchanging genes or can interbreed</u>. In the above statement, birds who are interbreeding with each other must be a single species.
c. A metapopulation is generically defined as the group of populations who are <u>separated by space</u> but are the <u>same species according to phylogenetic analysis</u>. Thus, the metapopulation of salamanders who are linked by gene flow (gene migration) should be treated as one species.
d. The word "<u>lineage</u>" already conveys the message that these bacteria belong share <u>sample place in the phylogenetic tree</u> and they are capable to adapt the same environmental niche. Therefore, they should be considered as one species. This can be easily tested via 16S rRNA sequencing.
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.
Sunlight and carbon dioxide
Answer:
directional selection
Explanation:
Directional selection is the most common type of natural selection and occurs when some individuals with characteristics favorable to the conditions of the environment in which they live, have survival advantages over individuals who do not have this advantage, who end up dying.
Imagine, for example, a graph showing the directional selection in the same species of moths. Moths of the same species have white and brown collations, in summer, brown moths can camouflage themselves on tree trunks, while white moths cannot and are easily captured by their predators, which means that the amount of white moths decrease. In this graph, the population of white moths would be at a minimum, at the same time that the population of brown moths would be at maximum.
However, with the arrival of the reverse, snow begins to cover the trees, allowing white moths to camouflage themselves more easily. The brown moths, then, are very exposed to predators, causing their population to reach the minimum while the population of white moths reaches the maximum.
Answer:
1. When the number of calories a person consumes is equal to the number of calories he or she burns in a day, that person's body is in Energy Balance.
2. Someone who is in Positive Energy Balance eats more calories in a day than he or she bums.
3. Negative Energy Balance occurs when the number of calories a person bums in a day is greater than the amount he or she consumes.
4. Weight management involves applying strategies that allow someone to keep his or her body weight within a healthy.
5. The Basal metabolic rate is the amount of energy uses in order to perform its basic physiological functions.
6. The Thermic effect of food refers to the number of calories burned in order to digest absorb, metabolze, and store food.
7. The Lean body mass refers to his or her total body - fat mass.
Explanation:
This group of statements are related to body weight, the balance between the energy we consume through food and all the energy we burn through excercise and different activities, such as only mantaining our body temperature and normal processes.
