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Answer: F T F T F
Answer: F
Answer: luteinizing hormone (LH)
Answer: A
Answer: B
Answer: B
Answer: B A D C
Answer: 1) risk characterization
Answer: A
Answer: 3
Answer: A
Answer: B
Answer: B
Answer: F

Using Flutter 2.7.10 (latest one) and Android Studio Electric Eel | 2022.1.1 Patch 1. Ran this Flutter program located in this Google Storage drive since it has so many parts to the program 

I got the error message below. Also attached screenshot of the error msg

Please run the program located in that Google Storage drive.

Because it works for some people, but not for others. Some people  get the error msg -

Other people it works fine. We all have the same flutter version and Android Studio. We are all using Windows 10 and 11.

Null check operator used on a null value

When the exception was thrown, this was the stack: 
#0      _TaskListPageState.getUID.<anonymous closure> (package:todolist/pages/tasklist/tasklist.dart:25:17)
#1      State.setState (package:flutter/src/widgets/framework.dart:1133:30)
#2      _TaskListPageState.getUID (package:todolist/pages/tasklist/tasklist.dart:24:5)
#3      _TaskListPageState.initState (package:todolist/pages/tasklist/tasklist.dart:18:5)
#4      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:5101:55)
#5      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4944:5)
#6      Element.inflateWidget (package:flutter/src/widgets/framework.dart:3953:16)
#7      Element.updateChild (package:flutter/src/widgets/framework.dart:3676:20)
#8      ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4993:16)
#9      StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:5133:11)
#10     Element.rebuild (package:flutter/src/widgets/framework.dart:4690:5)
#11     BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2743:19)
#12     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:863:21)
#13     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:381:5)
#14     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1289:15)
#15     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1218:9)
#16     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:1076:5)
#17     _invoke (dart:ui/hooks.dart:145:13)
#18     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:338:5)
#19     _drawFrame (dart:ui/hooks.dart:112:31)

Answer: The error message indicates that the null check operator (the exclamat...
Answer: The correct answer is (i) Excretion of biles. Renal function tests are...
Answer: Yes, the statement is referring to the nitrogenous waste product urea....
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Answer: the importance of effective communication in entrepreneurship: I'm tra...
Answer: The statement is not entirely accurate. Glucose does not directly acti...
Answer: A

1. Which of the following is/are required for retrotransposons to move from one location to another in the genome?

Select one or MORE:

a. RNA polymerase

b. DNA polymerase

c. ribosomes

d. reverse transcriptase


Which of the following is/are not commonly used in gene expression and cell replication in human cells?

Select one or MORE:

a. ribosomes

b. reverse transcriptase

c. DNA-dependent RNA polymerase (DNA-->RNA)

d. DNA-dependent DNA polymerase (DNA-->DNA)

e. RNA-dependent RNA polymerase (RNA --> RNA)


Ubiquitin can be added to lysine, cysteine, serine and threonine residues in proteins. The ubiquitination (addition of ubiquitin) of a protein would:

Select one:

a. target the protein to be translocated to the rough endoplasmic reticulum to continue translation of the peptide.

b. trigger the hydrolysis of its complementary mRNA sequence.

c. trigger alternative splicing of mRNA by snRNP.

d. trigger the removal of the pro-segment of a enzyme, activating it.

e. target the protein for breakdown by proteasomes in the cell.


miRNA can:

Select one or MORE:

a. form a complex with proteins that will block translation of mRNA containing complementary sequence

b. form a complex with proteins that will break down mRNA containing complementary sequence

c. remove introns from pre-mRNA in eukaryotes

d. fluoresce when complementary mRNA is present


Coordination of gene expression of enzymes required in a single metabolic pathway in eukaryotes would require:

Select one or MORE:

a. organization of genes into operons

b. the same combination of control elements for all genes in the pathway

c. alternative splicing of a single gene to produce all enzymes in a pathway

d. presence of the correct combination of activator proteins for the genes in the pathway

Answer: A
Answer: B
Answer: A
Answer: A

1. How are DNA hybridization techniques, developed decdes ago, used today in the field of identification and classification?

a) Older techniques are used for training purposes for young microbiologists

b)Are used to verify biochemical tests in the clinical lab to check on the microbiologist's lab skills

c)Have been adapted and used as DNA probes to identify unknown isolates

d) Used to overcome poor aseptic techniques in clinical labs

e) Used to verify that the clinical microbiologist paid attention in Micro lecture


2. Which of the following are important factors to consider in classifying bacteria species?

a) biochemical tests b) differential staining c) morphological characterisitics d) serological procedures e) all of the above are important considerations


3) Which types of microbes could be found growing at the very bottom of tubes of TSA (no O2)?

a) obilgate aerobes and microaerophiles b) facultative anerobes and obligate aerobes c) aerotolerant anerobes and facultative anaerobes d) microaerophiles and obilgate anaerobes

e) archaea and extreme halophiles


4) The use of salt and sugar in preserving various types of foods by limiting microbial growth is an application of which of the following concepts?

a) nitrogen fixation b) disinfectant inhibition c)pH d) Aw, water activity e) spicy cooking


5) A microbiologist inoculates a growth medium at Time 0 with 200 bacterial cells/ ml. If the generation time of the species is 30 minutes, and there is no lag phase, how long will it take the culture to reach a population of more than 3000 cells/ ml?

a) 1 hours b) 2 hrs c) 4 hrs d) 14 hrs e) 3000 minutes


6) UV light is not useful for disinfecting material in packages because

a) UV will cause mutations in the people who use the contents b) UV has no penetrating power, so it's only good for disinfecting surfaces

c) UV exposure can cause human cancer d) UV is too expensive to use for this purpose e) workers that handle the packages will get too tan


7) Which of the following controversial compounds has been used to preserve some vaccine components?

a) Hexachlorophene b) mercurochrome c) silver nitrate d) thimerosal e) Purell hand sanitizer


8) What is the glucose fermentation and motility of the Mannheimia species?

a) motile, glucose fermentation with gas b) motile, urea negative c) non-motile, Indole negative d) non-motile, acid and gas from glucose e) Not enough data


9) The advantage of using "Ultra-pasteurization" on dairy product is

a) it is inexpensive b) it kills all but the most hardy TB bacteria c) the process kills almost all microbes and greatly extends the shelf life d) spoilage is delayed a day or two for most products

e) the retailer can charge more money for the product and increase profits


10) Which method would allow the determination of a specific concentration of live bacteria in a sample?

a) turbidty measurement b) dry weight measurement c) serial dilutions and plate count d) direct microscopic count


11) Mycoplasma species have no cell wall but are known to be related to Gram-positive bacteria. Which of the following provides good evidence for this?

a) Some mucoplasmas and some G + bacteria produce catalase b) Genetic analysis shows that they share common 16S rRNA gene sequences c) Both groups are prokaryotic bacteria

d) Both groups have species that are coccus shaped e) These species are mentioned in the same text book


12) A latent virus is one that

a) has a long incubation period before initial symptoms begin b) remains attached to the host cells for a long time before it enters the cell c) remains hidden in the body and periodically causes recurring disease d) has sumptoms that are difficult to diagnose


13) Cells in a cell culture that fail to exhibit contact inhibition as they grow:

a) grow only in a monolayer b) will eventually pile up and form a tumor c) grow only as individual cells that do not touch other cells d) die if they come in contact with other cells


14) Viruses that penetrate the host cell by the process of fusion get into the cell by

a) injecting their DNA through the cell membrane b) the spikes opening up small holes c) breaking through the cell membrane with lipid enzymes d) the virus outer layer melting into the host cell membrane e) opening locked trap doors


15) A bacterial population treated with lethal heat will generally

a) die all at the same time since they are all exposed at the same time b) die at an exponential rate, exhibiting a strady decline over time c) die for shortperiod of time then recover and start growing again d) die in one log increments every minute, no matter what the temperature e) file a microbial excessive force complaint with the FDA


16) Why was hexachlorophene discontinued as an anti Staphylococcus agent in newborn baby nurseries?

a) it didn't control Staphylococcus aureus infections b) the babies became resistant the treatment c) the hexachlorophene was shown to be toxic when not used properly

d) too many Staph species became immune to its anti bacterial activity


17) What is the first step (in this list) that is necessary for animal virus replication?

a) viral sensing that it's close to a favorable host cell b) the virion bumping into and sticking to a host cell c) the lysis of the host cell d) the uncoating of the virus by enzumes

e) formal introductions by the parents


18) The "batch" and "continuous" pasteurization processes for dairy products such as milk

a) kill all spoilage microbes, making the milk sterile so it doesn't spoil in the refrig b) kill Mycobacterium tuberculosis and other pathogenic bacteria and makes the milk safe

c) increase the number of spoilage bacteria and hastens the spoilage in your refrig d) are very damaging to the taste quality of the milk, lowering economic value

e) are another plot by big gov. Pulbic Health officials to control your life


19) The development of the Salk vaccine for polio in the 1950s depended on

a) embryonated chicken eggs and liver tissue b) Monkey kidney cells, HeLa cells, and other cell culture advances c) primate neuro-tissue and epithelial stem cells

d)infant spinal cord and muscle neurons e) E.coli and Staphylococcus aureus

Answer: A
Answer: C
Answer: A
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