Insects, and some other invertebrates, exchange oxygen and carbon dioxide between their tissues and the air by a system of air-filled tubes called tracheae. Tracheae open to the outside through small holes called spiracles.
Answer:
The way I would separate the shell fragments from the sand would be by using a filter. As shell fragments are larger than sand. So I would use a filter with 2 mm spaces to separate them. Now, for the sand separation from the water, I would heat the water so it would evaporate and connect a tube to another recipient making the sand stay in the first tube and the water vapor cools in the tube to precipitate in the other recipient. Three mixtures I have prepared at home are chocolate milk, coffee and cream, and lemon juice and tea.
Explanation:
To understand this answer we have to remember a few things. First, mixtures always have solute and solvent. The solvent is the most liquid component of the mixture and it can incorporate the more solid element in its composition to carry it. Now, there are several methods to separate them, barrier methods like filters are the first and more basic ones, as they are aimed to separated big solutes. While evaporation can be used to separate two very liquid elements. Like distillation of alcohol to separate the most concentrated oil from the alcohol.
Answer:
Here are seven theories complied by the science daily LiveScience which suggests the origins of Life.
1 Panspermia.
2 Simple Beginnings. ...
3 RNA World. ...
4 Chilly Start. ...
5 Deep-Sea Vents. ...
6 Community Clay. ...
7 Electric Spark. ...
Explanation:
Hello There!
In a eukaryotic cell, transcription takes place in the nucleus.
Hope This Helps You!
Good Luck :)
- Hannah ❤
Answer:
B. The genetic variation for the trait was exhausted.
Explanation:
Oil content is a quantitative trait, ie., a phenotypic feature that depends on the accumulative effects of many genes and the interaction of a genotype with its environment. During crop improvement, the plants (i.e., lines) containing desired alleles involved in the variation of this trait will be selected, thereby increasing oil content but simultaneously decreasing the genetic variation of the population. In consequence, after successive rounds of artificial selection, lines will not have sufficient genetic diversity to be again selected for this trait.