The graph below shows the effect of environmental temperature on a girl's skin temperature and on her internal body temperature. Which statement best describes what happens as environmental temperature increases from 20ºC to 30ºC?

A. Both the internal and the skin temperatures reach 40ºC.

B. Both the internal and the skin temperatures increase by about 7ºC.

C. The skin temperature decreases to about 30ºC.

D. The internal temperature increases by about 1ºC.

Answer Explanation:

D) The internal temperature increases by about 1ºC.

- Correct: As environmental temperature increases from 20ºC to 30ºC, the body's internal temperature tends to increase slightly. This is due to the body's thermoregulatory mechanisms, which work to maintain a relatively constant internal temperature (around 37ºC or 98.6ºF) despite fluctuations in environmental temperature. When the environmental temperature rises, the body responds by increasing blood flow to the skin and by initiating mechanisms such as sweating to dissipate heat and maintain thermal equilibrium. However, the increase in environmental temperature may result in a slight increase in internal temperature, typically by about 1ºC, as the body works to dissipate excess heat.

A) Both the internal and the skin temperatures reach 40ºC.

- Incorrect: A 10ºC increase in environmental temperature from 20ºC to 30ºC is not likely to cause both internal and skin temperatures to reach 40ºC. Such a significant increase would likely lead to heatstroke or hyperthermia, which can be life-threatening.

B) Both the internal and the skin temperatures increase by about 7ºC.

- Incorrect: A 10ºC increase in environmental temperature is not likely to cause both internal and skin temperatures to increase by about 7ºC. Such a large increase in temperature would be excessive and would likely lead to severe heat-related illnesses.

C) The skin temperature decreases to about 30ºC.

- Incorrect: In response to an increase in environmental temperature, the body typically increases blood flow to the skin and initiates mechanisms such as sweating to dissipate heat. This would not result in a decrease in skin temperature to match the environmental temperature of 30ºC.

Therefore, the Correct Answer is D.

Q #1: Which phase of deglutition involves contraction of the longitudinal muscle layer of the muscularis?

A. voluntary phase

B. buccal phase

C. pharyngeal phase

D. esophageal phase

Answer Explanation

a) voluntary phase

- Correct: The voluntary phase of deglutition (swallowing) involves the initial voluntary movement of food from the mouth into the pharynx. During this phase, the tongue pushes the food bolus backward toward the oropharynx. Contraction of the longitudinal muscle layer of the muscularis propels the food bolus into the pharynx, which is part of the voluntary control of swallowing.

b) buccal phase

- Incorrect: The buccal phase of deglutition involves the initial formation of the food bolus and its movement toward the oropharynx by the coordinated action of the tongue and muscles of the cheeks. It does not involve contraction of the longitudinal muscle layer of the muscularis.

c) pharyngeal phase

- Incorrect: The pharyngeal phase of deglutition is involuntary and occurs when the food bolus reaches the pharynx. It involves the sequential contraction of muscles in the pharyngeal wall to propel the food bolus downward toward the esophagus. The contraction of the longitudinal muscle layer of the muscularis is not a significant component of the pharyngeal phase.

d) esophageal phase

- Incorrect: The esophageal phase of deglutition involves the passage of the food bolus through the esophagus and into the stomach. Peristaltic waves of contraction and relaxation of the muscularis propels the food bolus along the length of the esophagus. The contraction of the longitudinal muscle layer of the muscularis primarily occurs during the voluntary phase of deglutition, not the esophageal phase.
Q #2: Where does the majority of chemical digestion in the stomach occur?

A. fundus and body

B. cardia and fundus

C. body and pylorus

D. body

Answer Explanation

a) fundus and body

- Correct: The majority of chemical digestion in the stomach occurs in the fundus and body regions. These regions contain gastric glands that secrete hydrochloric acid (HCl), pepsinogen, and mucus. Hydrochloric acid creates an acidic environment necessary for the activation of pepsinogen to pepsin, which is responsible for the digestion of proteins. Additionally, the stomach churns and mixes food with gastric juices in the fundus and body, facilitating the breakdown of food particles and the mixing of digestive enzymes with the food bolus.

b) cardia and fundus

- Incorrect: While the fundus region is involved in chemical digestion due to the presence of gastric glands, the cardia region primarily serves as the entry point of the esophagus into the stomach and does not significantly contribute to chemical digestion.

c) body and pylorus

- Incorrect: While the body region of the stomach is involved in chemical digestion, the pylorus region is primarily responsible for regulating the passage of partially digested food (chyme) into the small intestine through the pyloric sphincter. The pylorus region does not contribute significantly to chemical digestion.

d) body

- Incorrect: While the body region of the stomach is involved in chemical digestion, the majority of chemical digestion occurs in both the fundus and body regions. The body region alone does not represent the entirety of where chemical digestion occurs in the stomach.
Q #3: Which human excretory organ breaks down red blood cells and synthesizes urea?

A. lung

B. kidney

C. skin

D. liver

Answer Explanation

D) liver

- Correct: The liver is the human excretory organ that breaks down red blood cells and synthesizes urea. Red blood cells have a finite lifespan and are continually replaced by new cells produced in the bone marrow. When old or damaged red blood cells are removed from circulation, their components are broken down by macrophages, primarily in the spleen and liver. The liver plays a crucial role in this process by breaking down hemoglobin, the oxygen-carrying protein in red blood cells, into heme and globin. Heme is further broken down into bilirubin, which is excreted in bile and eventually eliminated from the body in feces. Additionally, the liver synthesizes urea as a waste product of protein metabolism, which is excreted by the kidneys in urine.

A) lung

- Incorrect: While the lungs play a role in the excretion of carbon dioxide during respiration, they are not involved in breaking down red blood cells or synthesizing urea.

B) kidney

- Incorrect: The kidneys are responsible for filtering blood to remove waste products and excess substances, such as urea, creatinine, and electrolytes, to produce urine. While the kidneys excrete urea synthesized by the liver, they do not break down red blood cells.

C) skin

- Incorrect: The skin is involved in excreting certain waste products, such as sweat (containing water, electrolytes, and small amounts of urea and other metabolic waste), but it does not break down red blood cells or synthesize urea.

Free Access on TEAS 7 Exams and Study Notes

Access to all TEAS 7 Exams
Performance Tracking and Analysis
Well Documented and Explained Questions and Answers
2000+ Questions and Correct Answers: Answers Well Explained
Libary of Detailed StudyNotes
Topical Questions and Answers on Examinable topics

Join Now

The graph below shows the effect of environmental temperature on a girl's skin temperature and on her internal body temperature. Which statement best describes what happens as environmental temperature increases from 20ºC to 30ºC?

More Questions on TEAS 7 Science

Q #1: Which phase of deglutition involves contraction of the longitudinal muscle layer of the muscularis?

Answer Explanation

Q #2: Where does the majority of chemical digestion in the stomach occur?

Answer Explanation

Q #3: Which human excretory organ breaks down red blood cells and synthesizes urea?

Answer Explanation

Free Access on TEAS 7 Exams and Study Notes

TEAS 7 Exams (Q&A)

TEAS 7 Study Notes

TEAS 7 Topical Tests

TEAS 7 Study Guides

Quick Links

Refer a Friend

The graph below shows the effect of environmental temperature on a girl&#39;s skin temperature and on her internal body temperature. Which statement best describes what happens as environmental temperature increases from 20&ordm;C to 30&ordm;C?

More Questions on TEAS 7 Science

Q #1: Which phase of deglutition involves contraction of the longitudinal muscle layer of the muscularis?

Answer Explanation

Q #2: Where does the majority of chemical digestion in the stomach occur?

Answer Explanation

Q #3: Which human excretory organ breaks down red blood cells and synthesizes urea?

Answer Explanation

Free Access on TEAS 7 Exams and Study Notes

TEAS 7 Exams (Q&A)

TEAS 7 Study Notes

TEAS 7 Topical Tests

TEAS 7 Study Guides

Quick Links

Refer a Friend

The graph below shows the effect of environmental temperature on a girl's skin temperature and on her internal body temperature. Which statement best describes what happens as environmental temperature increases from 20ºC to 30ºC?