Answer:
B. polio—polyhedral shape
Explanation:
A virus is a small parasite which cannot self reproduce. For a virus to produce more viruses, it uses the cell to duplicate itself. Viruses contain RNA or DNA as their genetic material.
Poliovirus is composed of an RNA genetic material and it is responsible for Polio. Polio leads to paralysis and is transmitted through contaminated water or food, or contact with an infected person.
The shape of Poliovirus is formed by polyhedral (many-sided) shell or capsid.
<span>Damming a river has a variety of effects on the freshwater ecosystem, more than just altering the flow from A to B. Dams create calm bodies of water, changing overall temperature regimes and sediment transport, leading to conditions which tend to favour generalist species. Loss of specialist species, particularly endemics, changes the community structure and leads to biotic homogenization. A dam will withhold sediment in the reservoir, not just decreasing the amount of substrate available to local freshwater species, but even impacting diadromous, estuarine and marine species much further downstream. The competition between resident species for food and breeding sites will increase as damming isolates populations, and perhaps more importantly, damming completely restricts migratory fish species. Isolation may lead to decreases in genetic diversity and therefore puts species at greater risk from disease. All of these effects may be exacerbated by changes in the surrounding land use. Overall, damming river flow will lead to both a loss of native species, but also an increase in exotic species which are more likely to become established in degraded habitats. For this reason, dams are one of the greatest global threats to freshwater biodiversity.</span>
784109 People per sq. mi land would its people need if the population density is 3,826 people/km2.
<h3>
What is population density?</h3>
The density of individuals within a species in a given geographic location is referred to as population density. Data on population density can be used to calculate demographics and examine interactions with ecosystems, human health, and infrastructure.
The population density equation below can be used to calculate the population density of a piece of land:
Population Density = Population/ Area
The residential density is important in determining the people's thinking and culture. Engineers find it vital to forecast population growth in order to develop infrastructure that can support a large population. It is practically impossible to develop a perfect 3D model of any structure that allows the largest number of people to live without this understanding.
For more information regarding population density, visit:
brainly.com/question/109266
#SPJ1
The Gymnosperms and Angiosperms are groups of plants with seed, which means that they don’ t necessary acquire water for fertilization. These groups have made adaptations for sexual reproduction on dry land.
1) Gymnosperms (plants with the seeds are not enclosed in an ovary) have developed over the course of its evolution, structures that solved the main limitations present in the Pteridophytes in relation to sexual reproduction, in the terrestrial environment. The main changes that happened as an evolutionary adaptation to dry land are those on the seeds and pollen. The advantages of the seeds are: the storage tissue which sustains growth and a protective coat of the seeds. Seed is enveloped with the layers of hardened tissue which prevents desiccation. This is what frees reproduction from the need for a constant supply of water. <span>The sperm (male gamete) of gymnosperms</span> is enclosed in a pollen grain. Thi structure is protected from desiccation and can reach the female organs without dependence on water. Gymnosperms also developed structures called cupules to enclose and protect the ovule (the female gametophyte) which will develop into a seed upon fertilization.
2) Angiosperms are a group of plants which protect their seeds within an ovary called a fruit. Angiosperms have special evolutionary adaptations. For example, they produce their gametes in separate organs, usually in a flower, so the fertilization and embryo development takes place inside an anatomical structure. That provides a stable system of sexual reproduction largely sheltered from environmental fluctuations like water need.