BIOL121 WORKSHEETDue: 3am Tuesday 15th MaySubmit: via Turnitin link on BIOL121 LEO pageWeighting:...

Question

BIOL121 WORKSHEETDue: 3am Tuesday 15th MaySubmit: via Turnitin link on BIOL121 LEO pageWeighting: 20% final gradeQUESTION 1Which type of immunity is expressed in the following scenarios? Choose between:· Non-specific (first line defence)· Specific (antibody-mediated) · Specific (cell-mediated immunity)(0.5 mark each – total 2 marks)    Scenario    Type of immunity    Bacterial septicaemia (bacterial contamination in systemic circulation)         The pH of hydrochloric acid in the stomach acts to destroy ingested bacteria        A liver cell mutates and becomes cancerous        A virus multiplies inside the epithelial cells in your throat.    QUESTION 2Describe how bone cells respond to the hormones involved in the homeostasis of blood calcium ion concentration.  (3 marks)QUESTION 3Choose ONE of the below scenarios and highlight this row bold.  State which general property of adaptive immunity the scenario illustrates in the second column. Select ONE phrase (from the list below) that BEST describes what is happening at a cellular level to result in this property of adaptive immunity. Write the letter coesponding to this phrase in the third column.  An example is included in italics.  (1 mark)    Scenario    General property of immunity     Explanation     Even though your body contains a relatively small number of lymphocytes, your immune system is capable of mounting a response against almost any antigen it encounters.    Versatility    A    Generally, after an initial infection, subsequent immune responses to that antigen are faster, stronger and more sustained.            You can suffer from ‘the flu’ multiple times throughout your lifetime.            Your immune system is capable of distinguishing between antigens on your own cells, and those of an invading pathogen.        Possible phrases are listed below. Not all phrases will need to be used and only ONE phrase is required per row. If you record more than one, you will not be awarded any marks for your explanation.      A    There are millions of different lymphocyte populations, each of which is sensitive to a different antigen. Lymphocytes proliferate when activated by their specific antigen.    B    The immune response ignores self-antigens and targets non-self antigens.    C    B cells differentiate into T cells to create a long-lived immune response.    D    Each T and B cell can recognise many antigens and respond to a wide variety of possible threats.    E    Each T or B cell has receptors that respond to only one antigen and ignores all others.    F    Phagocytes have a reduced ability to destroy pathogens during subsequent infections.    G    T cells are versatile because they produce copious quantities of antibodies that can respond to a wide variety of threats.    H    Activated lymphocytes produce two groups of cells: one group that attacks the invader immediately, and another that remains inactive unless it is exposed to the same antigen at a later dateQUESTION 4A. Using the patellar reflex as an example, explain the purpose of a neural reflex.  (2 marks)B. What happens to the patellar reflex when someone clasps their hands and squeezes them strongly? Why does this occur?  (2 marks)QUESTION 5Using the diagram provided as a prompt, outline the four steps involved in the transmission of an electrical impulse from the presynaptic neurone to the post synaptic neurone.  (4 marks)    Step    Outline    1        2        3        4    QUESTION 6Describe the series of events occuing at a neuromuscular junction required for muscular contraction. (3 marks)QUESTION 7Think about how the renin-angiotensin-aldosterone system acts to maintain normal blood pressure. Susan has sustained damage to her adrenal glands.  Consequently, her circulating levels of aldosterone are abnormally low.  A. Where are the target cells for aldosterone located in the body?  (1 mark)B. What do you expect the lack of aldosterone to do to Susan’s blood pressure? Explain your answer.  (3 marks)QUESTION 8Explain the term ‘normal sinus rhythm’.  (1 mark)QUESTION 9For each of the scenarios below, indicate whether you would you expect resting heart rate to be greater or less than that associated with normal sinus rhythm.  Explain the cardiac physiology underlying the identified change.  (4 marks)    Heart rate    Situation    Explanation        A person of average fitness running a 5km fun run.            An endurance athlete at rest.     QUESTION 10Explain how baroreceptors contribute to control blood pressure during a short period of widespread vasodilation.  (3 marks)QUESTION 11Parents, a father who is heterozygous for blood group A and a mother who is heterozygous for blood group B, are wondering what, if any, are their chances of producing a child with blood group O. A. State the genotype of each parent, and complete the Punnett square below.  (2 marks)                                        Parent    Genotype    Fathe        Mothe    B. What is the chance of these parents producing a blood group O child? Explain your reasoning. (1 mark)QUESTION 12Describe TWO differences between the intrinsic and extrinsic pathways in blood clotting.  (2 marks)QUESTION 13The Wigger’s diagram (below) represents pressure and volume relationships in the left side of the heart during one cardiac cycle.  To answer this question, you should focus on the changes in pressure in different chambers of, or vessels leading from, the left side of the heart. BDACFor ONE of the labelled points, state which valve is open/closed at that time.  Highlight your chosen point in bold.  You must also explain WHY that valve opened/closed and where the blood is flowing immediately after this point in time, due to the change in position of the valve.  An example is provided in italics.  (2 marks)    Label    Valve (name and open/closed)    Explanation    A            B            C            D    Left AVicuspid valve opens    The pressure in the left ventricle becomes lower than that in the left atrium.  Blood flows from the left atrium to the left ventricle.QUESTION 14Consider the events occuing after you have eaten a high caohydrate meal.  For each of the organs listed in the table below, describe ONE mechanical and ONE chemical digestion event that will contribute to the digestion of caohydrates.  (2 marks per location - 6 marks total)    Location     Mechanical digestion event    Chemical digestion event    Mouth            Stomach            Small intestine        QUESTION 15Continue to consider the events occuing after you have eaten a high caohydrate meal.  In the table below explain how the listed organs are involved in the absorption and metabolism events (specific to caohydrates) that occur after this meal. (1 mark per location - 2 marks total)    Location     Absorption and metabolism events    Small intestine        Live    QUESTION 16The figure below illustrates inspiration and expiration.  Refer to this figure to answer the following questions XXXXXXXXXXmarks each - 3 marks total)    Question    Answe    Contraction of which muscle/s produces the movement labelled "1"?        Contraction of which muscle/s produces the movement labelled “2”?        At label “3”, is pressure outside greater than or less than pressure inside the lungs?        Is the pressure in the space labelled "4", higher or lower compared to the atmospheric pressure?        At label “8”, is pressure outside greater than or less than pressure inside the lungs?        Name any ONE muscle that contracts to cause the extra movement required when you need to expire forcefully (indicated by the aows labelled "6" and "7").    QUESTION 17A. Complete the below table of partial pressures in internal respiration.  (1 mark)        pO2 (mmHg)    pCO2 (mmHg)    Capillary             Tissue             B. Describe how the differences in partial pressures drives the direction of gas movement between the blood and tissues  (2 marks)QUESTION 18A. Describe the epithelium lining in the trachea?  (1 mark)B. How does the structure of this epithelium relate to its function in the trachea?  (1 mark)QUESTION 19What personal protective equipment should be worn when handling someone else’s urine?  Explain.  (1 mark) QUESTION 20The results of dipstick urinalysis of two urine samples are listed below. Sample 1 belongs to a 16-year-old male ‘gamer’ who has locked himself in his room all weekend to play computer games (he didn’t really even come out to eat or drink).   Sample 2 belongs to a 22-year-old female triathlete who is careful with her diet, hydration, and almost exercises to excess. For each parameter, fill in the normal values. (Hint: Refer to the Week 10 laboratory activity to get you started).    Paramete    Normal values    Sample 1    Sample 2    Colou        Dark yellow    Reddish tinge    Glucose        -    -    Bilirubin        -    -    Ketones        ++    -    Specific gravity        1.039    1.010    Blood        -    ++    pH        5.5    6.0    Protein        -    ++    Nitrite        -    -    Leukocytes        -    -Choose ONE of the samples described above and answer the following questions in the space provided. A. Compare the normal and sample values. List any abnormalities you observe in the section below. Are they higher or lower than normal?  (1 mark) B. Give a situation in which you might expect to see these changes in an otherwise healthy individual.  (1 mark) C. What might have been happening in the nephron to cause these abnormal results? Explain your observed abnormalities by linking them with the part of the nephron involved and the process involved (ie filtration, secretion or reabsorption).  Ensure that any relationships between the abnormal readings are made clear in your response.  (2 marks)     Chosen sample:    A        B        C    QUESTION 21In regards to the nervous endocrine system, explain the appearance of urine with a higher than normal specific gravity.  (3 marks)5

Soumi · Accepted Answer

BIOL121 WORKSHEET
Due: 3am Tuesday 15th May
Submit: via Turnitin link on BIOL121 LEO page
Weighting: 20% final grade
QUESTION 1
Which type of immunity is expressed in the following scenarios? Choose between:
· Non-specific (first line defence)
· Specific (antibody-mediated) 
· Specific (cell-mediated immunity)
(0.5 mark each – total 2 marks)
	Scenario
	Type of immunity
	Bacterial septicaemia (bacterial contamination in systemic circulation) 
	Specific (antibody-mediated)
	The pH of hydrochloric acid in the stomach acts to destroy ingested bacteria
	Non-specific (first line defence)
	A liver cell mutates and becomes cancerous
	Specific (cell-mediated immunity)
	A virus multiplies inside the epithelial cells in your throat.
	Specific (cell-mediated immunity)
QUESTION 2
Describe how bone cells respond to the hormones involved in the homeostasis of blood calcium ion concentration. (3 marks)
The homeostasis of calcium ion within the blood takes place due to three types of hormones— calcitonin, parathyroid hormone (PTH) and 1 alpha, 25-dihydroxy-Vitamin D. the impact of PTH upon the bone is in three forms— firstly, it directly lays impact on the stimulation of the resorption of the bone, secondly, 1 alpha, 25-dihydroxy-Vitamin D production is stimulated and thirdly, the recovery of calcium from the kidneys is initiated by this hormone. Now when the calcium is recovered, its flow from and to the bones is initiated with the help of this process of calcium homeostasis. As mentioned by Fan et al. (2015), vitamin D is responsible for the bone strength, which is converted into calcifediol inside the liver and into calcitriol inside the kidneys. When the resorption takes place inside the bones, the osteoclasts are responsible for this function and release calcium in the blood, to regulate the process and maintain bone strength.
QUESTION 3
Choose ONE of the below scenarios and highlight this row bold. State which general property of adaptive immunity the scenario illustrates in the second column. Select ONE phrase (from the list below) that BEST describes what is happening at a cellular level to result in this property of adaptive immunity. Write the letter corresponding to this phrase in the third column. An example is included in italics. (1 mark)
	Scenario
	General property of immunity 
	Explanation 
	Even though your body contains a relatively small number of lymphocytes, your immune system is capable of mounting a response against almost any antigen it encounters.
	Versatility
	A
	Generally, after an initial infection, subsequent immune responses to that antigen are faster, stronger and more sustained.
	Memory
	H
	You can suffer from ‘the flu’ multiple times throughout your lifetime.
	Specificity
	A
	Your immune system is capable of distinguishing between antigens on your own cells, and those of an invading pathogen.
	Autoimmunity
	B
Possible phrases are listed below. Not all phrases will need to be used and only ONE phrase is required per row. If you record more than one, you will not be awarded any marks for your explanation. 
	A
	There are millions of different lymphocyte populations, each of which is sensitive to a different antigen. Lymphocytes proliferate when activated by their specific antigen.
	B
	The immune response ignores self-antigens and targets non-self antigens.
	C
	B cells differentiate into T cells to create a long-lived immune response.
	D
	Each T and B cell can recognise many antigens and respond to a wide variety of possible threats.
	E
	Each T or B cell has receptors that respond to only one antigen and ignores all others.
	F
	Phagocytes have a reduced ability to destroy pathogens during subsequent infections.
	G
	T cells are versatile because they produce copious quantities of antibodies that can respond to a wide variety of threats.
	H
	Activated lymphocytes produce two groups of cells: one group that attacks the invader immediately, and another that remains inactive unless it is exposed to the same antigen at a later date
QUESTION 4
A. Using the patellar reflex as an example, explain the purpose of a neural reflex. (2 marks)
The key purpose of neural reflexes is to detect if there is any dysfunctionality within the central nervous system (CNS). As stated by Willemze, Luyer, Buurman and De Jonge (2015), when a person is able to respond to any stimulus that is imposed to them physically, they can be considered as sound in terms of neural functionality. Hence, neural reflexes help in the detection of the health of the CNS. It is an entire pathway that is initiated at the receptor cell, tissue and muscle, and progresses to spinal cord without reaching the brain, following a path called the reflex arc. This reflex arc consists of both the sensory or afferent nerves and motor or efferent nerves, which initiate from the receptor and end at the effector organ, muscle or cell respectively. Hence, citing the example of patellar reflex, it can be said that the functionality of the neurons are checked using a reflex hammer to hit the patellar tendon below the patella so that it can be affirmed that the muscles are reactive to the neural reflex imparted to them on being hit.
B. What happens to the patellar reflex when someone clasps their hands and squeezes them strongly? Why does this occur? (2 marks)
The patellar reflex occurs when someone hit the person with a reflex hammer below the patella to check if their neural functionality is proper or not. Therefore, when the strike is received at the area below the patellar muscle, the leg muscles receive a reflex from the spinal cord, which makes it to kick in the forward direction. However, when the person, who is being hit clasps their hands tightly, the kick is failed to happen. It is so because then the reflex arc is not facilitated due to a modified and turned reflex pathway (Fernandez et al., 2014). Therefore, in such a bent, the impulse fails to travel to the spinal cord, as a result thee reflex action being unable to be produced. This is why the kick does not occur.
QUESTION 5
Using the diagram provided as a prompt, outline the four steps involved in the transmission of an electrical impulse from the presynaptic neuron to the postsynaptic neuron. (4 marks)
	Step
	Outline
	1
	At first, the impulse reaches at pre-synaptic knob, where depolarisation of pre-synaptic membrane takes place. It helps to open the voltage gate of calcium channel. This leads to the diffusion of the calcium ions at the pre-synaptic knob, which further leads the synaptic vesicle to move towards the surface of the pre-synaptic knob, carrying the neurotransmitter, which is known as the acetylcholine. 
	2
	From this step, the fusion of the synaptic vesicles take place that fuse to the presynaptic membrane by rupturing its acetylcholine into the synaptic cleft. Post this discharge, the filling up of the synaptic vesicle is repeated as a cyclic process of refilling and emptying in the cytoplasmic matrix of the pre-synaptic knob. 
	3
	The third step is to bind the released acetylcholine to the protein receptors, those are found on the post-synaptic membrane of the adjacent neuron. This leads to cause a change in the membrane potential, where the acetylcholine, which is now not bound, disappears from the present synaptic cleft. 
	4
	The last step involves depolarising the post-synaptic membrane, which leads to opening the sodium channel. This channels lets the influx of the sodium ions, thus ending the cycle of transmission (Fields, 2015). 
QUESTION 6
Describe the series of events occurring at a neuromuscular junction required for muscular contraction. (3 marks)150
When a neuromuscular junction (NMJ) takes place for the muscular contraction, following are the four major events that take place:
a) Release of Acetylcholine (ACh): The release of the Ach takes place, when a nerve impulse reaches the end bulb of the synapse. It is a neurotransmitter that is released from the synaptic vesicle, which contain this Ach. The diffusion of the Ach takes place across the synaptic cleft that is present between the efferent neuron and its end plate. 
b) Activation of the ACh receptors: As mentioned by Hughes, Hixon and Josey (2016), this is followed by the second step, where the end plate of the efferent neuron serves as the binding site for the free ACh, which leads to the opening of the ion channels. This is why the passage of the sodium ions are facilitated across the muscular cell membrane.
c) Generating the action potential of the muscles: The third step involves the passage of the sodium ions to cross the muscular cell membrane, which is the muscle action potential is developed.
d) Breaking of the ACh: The last step to take place the NMJ is the breakdown of the ACh, which particularly takes place at the synaptic cleft. The product that is formed is known as the acetylcholinesterase (AChE), which is an enzyme. This ends the entire process of the neuromuscular junction thus, leading to the occurrence of the muscular contraction.
QUESTION 7
Think about how the renin-angiotensin-aldosterone system acts to maintain normal blood pressure. Susan has sustained damage to her adrenal glands. Consequently, her circulating levels of aldosterone are abnormally low. 
A. Where are the target cells for aldosterone located in the body? (1 mark)
The target cells for aldosterone are located at the distal part of the nephron in the body. Therefore, it is actually in the kidneys.
B. What do you expect the lack of aldosterone to do to Susan’s blood pressure? Explain your answer. (3 marks)
The key role of aldosterone is to stabilise the bodily functions. As stated by Hirohama et al. (2017),

BIOL121 WORKSHEET Due: 3am Tuesday 15th May Submit: via Turnitin link on BIOL121 LEO page Weighting: 20% final grade QUESTION 1 Which type of immunity is expressed in the following scenarios? Choose...

Solution

Answer To This Question Is Available To Download

Related Questions & Answers

Submit New Assignment