Ques: Answer the following question given this paragraph: Some prokaryotes form structures consisting of many individual cells, like the cells in Figure below . This is called a biofilm. A biofilm is a colony of prokaryotes that is stuck to a surface. The surface might be a rock or a host's tissues. The sticky plaque that collects on your teeth between brushings is a biofilm. It consists of millions of prokaryotic cells. Q: A biofilm is a colony of prokaryotes that is stuck to what? Choices: - the middle - the bottom - skin - surface A:
Ans: surface

Ques: Answer the following question given this paragraph: Vertebrates reproduce sexually, and almost all of them have separate male and female sexes. Generally, aquatic species have external fertilization, whereas terrestrial species have internal fertilization. Can you think of a reason why aquatic and terrestrial vertebrates differ in this way?. Q: In which way do vertebrates reproduce? Choices: - bisexually - unisexually - asexually - sexually A:
Ans: sexually

Ques: Answer the following question given this paragraph: Carl Woese and the Phylogenetic Tree In the past, biologists grouped living organisms into five kingdoms: animals, plants, fungi, protists, and bacteria. The organizational scheme was based mainly on physical features, as opposed to physiology, biochemistry, or molecular biology, all of which are used by modern systematics. The pioneering work of American microbiologist Carl Woese in the early 1970s has shown, however, that life on Earth has evolved along three lineages, now called domainsBacteria, Archaea, and Eukarya. The first two are prokaryotic cells with microbes that lack membrane-enclosed nuclei and organelles. The third domain contains the eukaryotes and includes unicellular microorganisms together with the four original kingdoms (excluding bacteria). Woese defined Archaea as a new domain, and this resulted in a new taxonomic tree (Figure 1.17). Many organisms belonging to the Archaea domain live under extreme conditions and are called extremophiles. To construct his tree, Woese used genetic relationships rather than similarities based on morphology (shape). Woese's tree was constructed from comparative sequencing of the genes that are universally distributed, present in every organism, and conserved (meaning that these genes have remained essentially unchanged throughout evolution). Woese's approach was revolutionary because comparisons of physical features are insufficient to differentiate between the prokaryotes that appear fairly similar in spite of their tremendous biochemical diversity and genetic variability (Figure 1.18). The comparison of homologous DNA and RNA sequences provided Woese with a sensitive device that revealed the extensive variability of prokaryotes, and which justified the separation of the prokaryotes into two domains: bacteria and archaea. Q: In the past, biologists grouped living organisms into five kingdoms: animals, plants, fungi, protists, and what? Choices: - trees - pathogens - lizards - bacteria A:
Ans: bacteria

Ques: Answer the following question given this paragraph: The mass lost in mass defect has gone into energy that is called binding energy. Q: The mass lost in mass defect has gone into energy called what? Choices: - momentum - enthalpy - kinetic energy - binding energy A:
Ans:
binding energy