Which food groups are often missing from high-calorie, energy-dense diets?
In: Biology
According to the abc model of floral development, which genes would be expressed in a showy ornamental flower with multiple sepals and petals but no stamens or carpels? Please explain your answer.
In: Biology
In: Biology
A microelectrode delivers a current pulse that depolarizes the presynaptic terminal above threshold. Describe the events that occur (in molecular detail) immediately after depolarization. Your answer should finish with the response of the postsynaptic neuron. The presynaptic neuron releases ACh and the postsynaptic neuron has ionotropic AChR.
what channels are activated in terminal?
what currents flows through the membrane? What direction? Why?
what are all the proteins involved in the release of ACh vesicles?
mechanism?
In: Biology
1) All living organisms, including bacteria, plants, humans and other animals, are made up of one or more cells. Explain why all living organisms need to have DNA. Include the words genes and proteins in your explanation.
2)Explain how a difference in the sequence of nucleotides in a gene could result in one boy being albino and the other boy having normal skin and hair color.
3)Copy and complete this chart to describe how a person's DNA determines whether he has hemophilia. (Hint: begin by completing the bottom box in the protein column.)
Gene in DNA |
Protein |
Characteristic |
Normal formation of blood clots prevents excessive bleeding. |
||
Hemophilia (excessive bleeding because clots do not form normally because one type of clotting protein is defective) |
4) Explain why a cell needs to replicate its DNA before the cell divides into two daughter cells.
In: Biology
Why does signaling through a peptide growth factor (such as Epidermal Growth Factor) allow for more rapid responses in a cell than signaling through a steroid hormone such as estrogen?
In: Biology
Answer for Cabbage:
In: Biology
Compare the facial prognathism and cranial capacity in apes and hominins. How do hominins differ from apes in their facial prognathism? Their cranial capacity?
How do apes and hominins compare with regard to their foramen magnum?
Why do apes have a larger nuchal area?
Why do apes have larger temporal muscles?
Why do apes have a larger zygomatic arch?
What is the function of the brow ridge?
What is the function of the sagittal crest?
How do the teeth and jaws of apes compare to the teeth and jaws of hominins?
What is a canine diastema? Do we see this in hominins? Explain your answer.
One structure appears to increase in size in hominins, what is it?
What structures (there are several!) decrease in size in hominins compared to apes?
In: Biology
Indicate whether the individual volunteering to donate blood for homologous transfusion should be accepted or deferred.
A. Defer Temporarily B. Defer for 6 Months C. Defer Permanently D. Accept E. Accept After Obtaining Medical Approval
(Are these answers correct?)
In: Biology
Labster - Bacterial Growth Curves Extension
Learner Outcomes
BI280-04 Compare and contrast the growth and reproduction of
microorganisms.
BI280-04.02 Compare the phases of microbial growth and describe the
relation to generation time.
Lab Extension
At 82% progress is this lab simulation you are asked to create your
own experiment.
What observation or questions are you investigating
with this experiment?
Write down your hypothesis.
Describe the experimental design .
Define the term control group. Which tube is the
control?
Define the term experimental/treatment group. Which
tube is the experimental/treatment group?
Define independent variable. In this experiment what
is the independent variable?
Define dependent variable. In this experiment what is
the dependent variable?
. Describe the data collected from the experiment.
Include the temperatures you tested and how the growth curves
differed. Describe differences (if any) in the lag phase,
exponential phase, stationary phase, and death phase. At this point
do NOTinterpret the results.
Was your hypothesis supported or rejected?
Interpret the results to draw a conclusion. Think
about WHY you had the results you did
and HOWthis relates to temperature as a limiting factor
in bacterial growth.
In: Biology
Give the correct term for the following
a-A developing embryo
b-Second phase of seed development after cell division.
c-The mature ovary wall that develops into a fruit wall.
d-The oil bodies on the outside of seeds
e-The pathway of water between living cells via the plasmodesmata
f-Root system formed from a strongly developed primary root and its branches
g-. The central column of cells in the root cap.
h-Negatively gravitropic air roots
i-Large intercellular air spaces in aquatic and wetland plants
j-The central area of the stem or root that contains procambium derived tissues and includes the vascular tissue, pith occasionally and a pericycle
In: Biology
OUTLINE the differences in the envelope structures of Gram-positive and Gram-negative bacteria. You may use diagrams or a table.
Describe the behavior of chemotaxis in bacteria. Make sure to mention how the flagella contributes and how they can move toward good things and away from bad things.
DESCRIBE the Endosymbiotic Theory and OUTLINE the evidence to support
In: Biology
Identify and briefly explain two advantages and two disadvantages of individual-level epidemiologic studies over rodent bioassays in assessing the public health hazard of a chemical
In: Biology
An aminoacyl-tRNA exhibits which one of the following characteristics?
A. |
It is produced by a synthetase that is specific for the amino acid, but not the tRNA |
|
B. |
It is composed of an amino acid esterified to the 5’ end of the tRNA |
|
C. |
It requires GTP for its synthesis from an amino acid and a tRNA |
|
D. |
It contains an anticodon that is complementary to the codon for the amino acid |
Concerning generation of ATP from glucose during glycolysis which of the following statements is not correct?
A. |
There is a net yield of 2 ATPs |
|
B. |
There is a net yield of 4 ATPs |
|
C. |
More ATP can be produced from the generated NADH in the presence of oxygen |
|
D. |
Direct generation of ATP in glycolysis is an example of substrate level phosphorylation |
Insulin results in phosphorylation of acetyl-coA carboxylase, which stimulate fatty acid synthesis?
True
False
Which of the following statement(s) is or are correct?
A. |
Excess proteins are stored as peptides in humans |
|
B. |
Excess even chain fatty acids can be used to synthesize glucose through gluconeogenesis |
|
C. |
Glycogen is one of the substrate for gluconeogenesis |
|
D. |
Excess dietary proteins can be stored either as glycogen or lipids |
|
E. |
All of the above |
Which of the following would be observed in a person who is resting after an overnight fast?
A. |
Liver glycogen are completely depleted |
|
B. |
Liver gluconeogenesis is not an important process |
|
C. |
Muscle glycogen stores are used to maintain glucose |
|
D. |
Fatty acids are released from adipose triacylglycerol stores |
|
E. |
The liver is oxidizing ketone bodies to meet its energy needs |
In: Biology
Q1. Cell survival curves
Suppose you did an experiment to generate a cell survival curve.
a) Describe what steps you would take to do the experiment.
b) What is meant by plating efficiency?
c) In your experiment you irradiate cells using 6 MV photons on a linear accelerator. You collect the data shown in the table below. Plot cell survival as a function of dose and use the linear-quadratic model to fit the data.
d) Determine the alpha/beta ratio from the curve fit. Is this an early responding or late responding cell line?
Number of cells plated |
Number of colonies counted |
Dose (Gy) |
100 |
75 |
0 |
400 |
255 |
2 |
400 |
180 |
5 |
1000 |
150 |
10 |
10000 |
90 |
20 |
In: Biology