QUESTION 46
Which one of the following is a human blood type?
ABO- |
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Rh+ |
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E+ |
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B- |
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Rh |
1 points
QUESTION 47
Which one of the following statements correctly describes activities of muscles?
All muscles shorten when they contract. |
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All muscles are attached to bones. |
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All muscles produce movement. |
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All muscles are under conscious control. |
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All muscles are synergistic. |
1 points
QUESTION 48
Which one of the following tissues can respond to the environment by generating electrical signals?
dermis |
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nervous |
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connective |
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muscle |
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epithelial |
1 points
QUESTION 49
Which type of microscope has the best resolution?
Leeuwenhoek's microscope |
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Hooke's microscope |
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An electron microscope |
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A modern light microscope |
1 points
QUESTION 50
Which type of tissue is able to contract?
dense connective |
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epithelial |
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nervous |
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muscle |
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loose connective |
In: Biology
QUESTION 36
Vasoconstriction is a term that refers to the contraction of muscle in the walls of the blood vessels, thus causing the diameter of the blood vessel to decrease. Which one of the following types of muscle would be involved in this contraction?
both cardiac and smooth |
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cardiac |
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smooth |
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both skeletal and smooth |
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skeletal |
1 points
QUESTION 37
Vertebrae belong to this category of bones.
long |
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short |
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irregular |
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flat |
1 points
QUESTION 38
What general type of tissue is characterized by few cells, separated by a nonliving extracellular matrix?
nervous tissue |
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connective tissue |
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organ tissue |
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epithelial tissue |
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muscle tissue |
1 points
QUESTION 39
What is NOT a feature of a prokaryotic cell?
Ribosomes |
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Enzymes |
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A nuclear membrane |
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A plasma membrane |
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DNA |
1 points
QUESTION 40
What would happen if the plasma membrane were composed solely of phospholipids and no proteins?
All movement of molecules across the membrane would cease. |
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Facilitated diffusion, active transport, and osmosis would not occur. |
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Simple diffusion and osmosis would continue to occur. |
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Immune reactions would not be affected. |
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The movement of molecules across the membrane would not be affected. |
In: Biology
what is interesting to know about the treacha wall in the respiratory system and what are its fuctions.
In: Biology
Using the example of a cat, what is the direction toward the head? toward the midline? toward the abdominal surface? the area supporting the forelegs?
In: Biology
Q1. Fill in
In 2016, The American Sheep Industry Association released data showing that the nation's 88,000 sheep producers generated a total economic impact of $5.8 billion. Some of the issues that impact the profitability of sheep include their coat color, how quickly they gain weight, and whether they are resistant to infection caused by parasitic worms called nematodes. In the UK last year, approximately 100 million dollars were spent on reducing and curing worm infections in sheep. A team of researchers led my Riggio and Matika are working on understanding the genetics of sheep in order to increase profitability. While sheep have hundreds of thousands of genes on their total of 54 chromosomes (n=27), the researchers are focusing on 3 genes. The NR gene is correlated with nematode resistance and is located on chromosome 14. Only individuals with two recessive copies show resistance to nematode infection. The GTH gene is correlated with growth rate and overall bodyweight. The researchers would like to have sheep grow quickly so they are ready for market sooner. Individuals with GG or Gg grow the fastest and reach market weight sooner than individuals with gg. Finally, there are two genes involved in coat color. They are both on chromosome 3, meaning they are linked. The first determines if the individual is Black (BB or Bb) or brown (bb). The second determine if there are white spots on the coat. The spotting gene shows no spotting with the NN genotype, spotting only on the head with the SN genotype, and spotting covering a majority of the body with the SS genotype.
Q1 Fill in the table below to help you keep track of the genes.
Chromosome # Possible Alleles Possible Genotypes Resulting Phenotyp
3 B or b BB or Bb or bb Black, black, brown
Coat Color S or N
13
Growth Rate G or g
14
Nematode Resistance R or r
Q2. In order to confirm that the NR gene controls resistance to infection from nematodes, the researchers want to perform a study to test their idea that individuals with the genotype “rr” have a lower risk of getting infected by nematodes than individuals with RR or Rr genotypes.
a. What is the null hypothesis for the study?
b. What is the alternative hypothesis for the study?
The methods used in the study are explained below:
The genotype of 300 baby sheep were determined prior to the study and approximately the same number of genotype RR, Rr and rr were used. They were raised in the same pastures and fed similar food. Fecal samples were collected from the rectum of the baby sheep at approximately 16, 20 and 24 weeks of age. Fecal egg counts of nematodes were measured on four replicates of each fecal sample and the average of the four replicates at each time point was used for analyses.
Q3. Draw a figure that would show support for the alternative hypothesis. Make sure to clearly label your axes, values (tick marks), and include an appropriate figure legend below the figure.
Q4. One of the sheep in the study is Dolly. She is brown with spotting on her head. She is heterozygous for the growth rate gene and shows resistance for nematode infection.
a. What is the genotype of Dolly?
b. Draw one of Dolly’s cells during metaphase of mitosis. Show chromosomes 3, 13, and 14. Label all the alleles. Label sister chromatids once in your model. Label homologous pairs once in your model.
c. Describe what the products of mitosis would be for Dolly.
d. Describe one reason why Dolly would need to perform mitosis.
A new Spartan sheep farm is starting to increase their flock and they are going to breed two sheep to produce a variety of colors and high resistance to nematode infection.
A female named Sally with the genotype: Bb NN rr GG with a male, Buster, with the genotype bb SN rr Gg
Q5. Draw a puffy stick chromosome model showing for chromosomes 3, 13, and 14 for Buster before DNA replication. Clearly show the locus for the genes and label the particular alleles.
Q6
a. Are there homologous pairs in this model? State Yes or No and explain you know.
b. Are there identical sister chromatids in this model? State Yes or No and explain.
Q7. Draw puffy stick chromosome models showing the homologous pairs for chromosomes 3, 13, and 14 Buster during metaphase of Meiosis I. Represent the two possible alignments of the chromosomes, due to independent assortment in A) and B). Clearly label all alleles for all genes. Also, label the sister chromatids and homologous chromosomes in at least 1 instance in your drawings if they are present.
Q8. Draw puffy stick chromosome models showing the homologous pairs for chromosomes 3, 13, and 14 Buster during metaphase of Meiosis II for alignment A above AND then the final products. Clearly show the locus for the genes and label the particular alleles.
Meiosis II, Alignment A:
Final Products of Meiosis II for Buster in Alignment A:
Q9. For Q7 and Q8, Write haploid or diploid next to each model. Then below explain how you know the difference:
Q10. In the space below, draw the Punnett square for the cross between Sally and Buster
Sally with the genotype: Bb NN rr GG Buster, with the genotype bb SN rr Gg
Q11. What would be the expected percentage or fraction of the offspring that would be brown with spotting on the head, be resistant to nemotodes and be heterozygous dominant for growth rate?
Q12. If you had 5 generations in a row of sheep that either had no spotting or had spotting only on the head and then a baby sheep appeared with spotting all over the body, what is one possible explanation? Explain your thinking.
Q13. If these scientists wanted to put the “n” allele into goats to help fight nematode infection, would they be doing gene editing or creating a genetically modified organism? Explain?
Only need questions 5-13 if you can understand it
In: Biology
Please do not Quote from another writter. handwitten work much
preferred.(3 pages needed)
Describe how an ultrasound transducer works? Include a discussion
of the energy form used to create images and how that interacts
with tissues in the body.
In: Biology
Why is there a debate about Australopithecus afarensis bipedalism?
In: Biology
In: Biology
Horses have 64 chromosomes and donkeys 62. The sterile hybrid between a horse and donkey is called a mule. In 1985 a mule named Krauss gave birth to foal named Blue Moon who was also a mule, and then in 1987 to another mule foal named White Lightning. Krauss was routinely pastured with other mules and horses but not donkeys. Explain this unusual occurrence.
In: Biology
4. Termination of replication in prokaryotes
5. Which of the following statements regarding r RNA is correct:
a) The most common of all RNA structures
b) It comes in the form of a single-chain molecule
c) It comes in the form of a double-stranded molecule
d) The structure contains a large number of loops, loops and bubbles
e) It comes in the nucleus of the cell
6. The characteristics of m RNA synthesis are:
a) takes place in the nucleus of the cell
b) takes place in the cytoplasm of the cell
c) nucleotides are linked by phosphodiester bonds
d) takes place on the DNA coding strand
e) energy from the hydrolysis of pyrophosphate is required for the process of m RNA biosynthesis
7. Leucine - zipper proteins
8. Lac operon
9. The significant difference between prokaryotes and eukaryotes is as follows:
a. Prokaryotes do not have DNA, as genetic material, while eukaryotes have
b. Prokaryotes do not have ribosomes, while eukaryotes have
c. Prokaryotic cells are not membrane-bound, whereas eukaryotic ones are
d. Eukaryotic DNA floats freely in the cell, while prokaryotic DNA is located in the cell nucleus
e. Nothing is true
In: Biology
You have ordered a set of enzymes that includes a protease, a DNase, and a RNase. Unfortunately, the company that you ordered them from failed to label the tubes with the specific enzymes and they are only labeled A, B and C. In your lab you have two strains of bacteria that are transformable. Strain Q is prototrophic but sensitive to the antibiotic streptomycin and strain R is auxotrophic for tryptophan but resistant to streptomycin. How might you devise an experiment to determine which tube contains DNase?
In: Biology
Glucose are stored as glycogen in muscle cells, from which it
can again be mobilized during exercise.
a) Write down the partial reactions as well as the net yield for
the conversion of glucose-6-phosphate to glycogen and for the
conversion of glycogen to glucose-6-phosphate.
b) Calculate the energy required for the consumption of the total
process of converting glucose-6-phosphate to glycogen and back to
glucose-6-phosphate expressed as energy-rich phosphate bonds (ATP
equivalents).
ΔG0’ for the reaction: ATP + H2O → ADP + Pi = –30.5 kJ∙mol-1.
c) Calculate ΔG’ for the reaction at 25 °C and pH 7, when [ATP] = 5
mM, [ADP] = 0.5 mM and [Pi] = 1.0 mM.
Phosphocreatin constitutes a small extra storage of energy within
muscle cells, and is formed from phosphorylation of creatin. The
reaction is catalyzed by creatine kinase and ΔG0’ for the reaction
is +2.3 kJ∙mol-1 (progressing towared the formation of
phosphocreatin).
d) Calculate how much phosphocreatin formed relative to creatin at
equilibrium in the creatin kinase catalyzed reaction (assuming the
same temperature, pH and concentrations of ATP and ADP as indicated
in the previous question).
In: Biology
The protein synthesis in pro- and eukaryotic species resembles
each other to a large degree. In both pro and eukaryotic cells,
mRNA is used as template for incorporation of the correct amino
acids in the growing polypeptide chain.
a) List the main differences between mRNA from prokaryotic and
eukaryotic species
b) In contrast to prokaryotic cells, eukaryotic cells has
spliceosomes, what function do they have? and list the main steps
in the reaction
c) How many different codons code for amino acids?
d) Explain why the number of different tRNA molecules is lower,
than the number of different codons?
In: Biology
The transport of Potassium across a eukaryotic membrane can
happen by either a passive or an active transport. The active
transport is used when Potassium has to move against the
concentration gradient that is from a low concentration outside
cells to a high concentration inside cells. Ion channels mediate
the passive transport and these transport ions from a high
concentration to a low concentration.
The Potassium channel is very selective for the transport of
Potassium.
a) Explain how the selectivity of the potassium channel is ensured
and why the smaller ion lithium will not be transported through the
potassium channel.
The gene encoding the Potassium channel in eukaryotes is
transcribed into a pre-mRNA.
b) List the three elements in a pre-mRNA in eukaryotes that is not
found in a prokaryotic mRNA?
c) RNA polymerase II is responsible for the transcription of the
gene encoding the Potassium channel; the carboxyl-terminal domain
of the RNA polymerase II has a special function, describe the
function?
d) Give the post-translational modification, which is responsible
for the regulation of the activity of the carboxyl-terminal domain
of RNA polymerase II.
In: Biology
The protein synthesis can be divided in three phases: initiation, elongation and termination.
a. Describe the initiation phase as it takes place in bacteria.
b. The initiation phase in pro- and eukaryotes begin differently, when it concern the recognition of mRNA, describe these differences.
c. tRNA transport amino acids to the ribosome. Which part of the tRNA molecule form a covalent link to the amino acid? And what is the name for the general class of enzymes that catalyse the formation of a covalent bond between tRNA and aminoacids?
d. Describe the mechanism which ensure that only the amino acid threonine is attached to threonyl-tRNA.
In: Biology