WorksheetsQuiz on Protein Functions and Growth
Total questions: 98
Worksheet time: 49mins
Which of the following is required for the process of growth in the body?
Net synthesis of proteins
Breakdown of carbohydrates
Absorption of fats
Elimination of waste
What is one of the main roles of proteins in the body according to the information provided?
They are the building blocks for the body
They store genetic information
They provide insulation
They transport oxygen
Which of the following is NOT a process included in growth?
Lengthening of the long bones
Increase in the size and number of cells in soft tissues
Decrease in muscle mass
Promotion of muscle growth
Proteins contribute to muscle growth and maintenance by:
Helping maintain muscle mass and promoting muscle growth
Only providing energy for the body
Being used to store fat in the body
Being responsible for bone mineralization
Stunted growth and reduced muscle mass in a patient could be due to which of the following underlying issues?
Insufficient synthesis of proteins
Excessive carbohydrate intake
High levels of fat storage
Increased bone density
Which of the following is a direct metabolic effect of growth hormone (GH) on adipose tissue?
Increases blood fatty acids levels by enhancing breakdown of triglycerides
Increases glucose uptake by muscles
Decreases glucose output by the liver
Inhibits amino acid uptake
How does growth hormone (GH) affect skeletal muscle?
Increases blood glucose levels by decreasing glucose uptake by muscles
Increases glucose uptake by muscles
Decreases blood fatty acids levels
Inhibits protein synthesis
What is the effect of growth hormone (GH) on the liver?
Increases glucose output by the liver
Decreases glucose output by the liver
Increases triglyceride breakdown
Stimulates insulin secretion
Which process is described as "glucose sparing" in relation to growth hormone (GH)?
GH reduces the use of glucose by tissues, preserving it for essential organs
GH increases glucose uptake by all tissues
GH stimulates insulin release
GH converts glucose to fatty acids
Growth hormone (GH) stimulates which of the following processes?
Amino acid uptake and protein synthesis
Decrease in blood fatty acids
Inhibition of glucose output by the liver
Decrease in protein synthesis
Growth hormone (GH) contributes to increased blood glucose levels in which of the following ways?
By decreasing glucose uptake by muscles and increasing glucose output by the liver
By increasing glucose uptake by muscles and decreasing glucose output by the liver
By stimulating insulin secretion and increasing glucose uptake by adipose tissue
By inhibiting protein synthesis and decreasing amino acid uptake
Which hormone is secreted by the pineal gland?
Melatonin
Insulin
Cortisol
Adrenaline
What is the primary function of melatonin in the human body?
Regulates blood sugar levels
Helps keep the body’s circadian rhythms in synchrony with the light-dark cycle
Increases heart rate
Stimulates muscle growth
Which cells in the pineal gland are responsible for secreting melatonin?
Neurons
Pinealocytes
Astrocytes
Erythrocytes
What happens to melatonin secretion during the light of day?
It increases to high levels
It remains unchanged
It falls to low levels
It stops completely
Which of the following is NOT a function of melatonin?
Promotes sleep
Acts as an antioxidant
Enhances immunity
Increases blood pressure
How does melatonin affect reproductive activity?
Stimulates reproductive hormones
Inhibits hormones that stimulate reproductive activity, including onset of puberty
Has no effect on reproductive hormones
Increases testosterone production
Which structure in the brain is referred to as the body’s biological clock and responds to light and dark?
Hippocampus
Pineal gland
Suprachiasmatic nucleus (SCN)
Thalamus
What is the shape and location of the pineal gland?
Large, oval-shaped structure in the cerebellum
Tiny, pinecone-shaped structure located in the center of the brain
Flat, disc-shaped structure in the spinal cord
Spherical structure in the frontal lobe
Which of the following best describes the structure of the thyroid gland?
It consists of a single lobe of endocrine tissue.
It consists of two lobes of endocrine tissue joined in the middle by a narrow portion, giving it a bow-tie shape.
It consists of three lobes of endocrine tissue.
It is a circular gland with no distinct lobes.
Which type of cell in the thyroid gland produces hormones derived from the amino acid tyrosine?
C cells
Parafollicular cells
Follicular cells
Beta cells
What are the two iodine-containing hormones produced by follicular cells in the thyroid gland?
Calcitonin and insulin
Tetraiodothyronine (T4 or thyroxine) and tri-iodothyronine (T3)
Adrenaline and noradrenaline
Glucagon and somatostatin
What is the main function of the peptide hormone calcitonin secreted by C cells in the thyroid gland?
Regulate blood sugar levels
Regulate levels of calcium and phosphate in the blood
Stimulate muscle contraction
Increase heart rate
The two types of endocrine secretory cells in the thyroid gland contribute to homeostasis in the body by:
Both cell types only regulate blood pressure.
Follicular cells produce hormones that regulate metabolism, while C cells secrete calcitonin to regulate calcium and phosphate levels, both contributing to overall homeostasis.
Follicular cells and C cells both produce insulin for glucose regulation.
C cells produce digestive enzymes, while follicular cells regulate heart rate.
Which molecule serves as the main site for most steps in thyroid hormone synthesis?
Thyroglobulin (Tg)
Hemoglobin
Insulin
Albumin
What is the role of the endoplasmic reticulum-Golgi complex in thyroid hormone synthesis?
It produces thyroglobulin (Tg)
It stores iodine
It breaks down hormones
It transports oxygen
Which amino acid is incorporated into the thyroglobulin molecule during its production?
Tyrosine
Lysine
Methionine
Glutamine
How is tyrosine-containing thyroglobulin (Tg) exported from the follicular cells into the colloid?
By exocytosis
By diffusion
By endocytosis
By osmosis
What happens to iodine (I) from the diet before it is used in thyroid hormone synthesis?
It is reduced to iodide (I-)
It is oxidized to iodate
It is converted to glucose
It is broken down to amino acids
Which mechanism allows the thyroid to capture iodide (I-) from the blood and transfer it into follicular cells?
Iodide pump (secondary active transport)
Simple diffusion
Facilitated diffusion
Passive osmosis
After being captured by the thyroid, how does active iodide (I-) enter the colloid?
It exits the cell through luminal channels
It is absorbed by endocytosis
It diffuses through the plasma membrane
It is transported by vesicles
The importance of the iodide pump in the synthesis of thyroid hormone is that it:
Ensures the active transport of iodide into follicular cells, which is essential for thyroid hormone synthesis.
Breaks down thyroglobulin.
Stores tyrosine in the colloid.
Converts iodine to glucose.
What is formed when one iodide (I-) attaches to tyrosine within the Tg molecule?
Diiodotyrosine (DIT)
Monoiodotyrosine (MIT)
Triiodothyronine (T3)
Tetraiodothyronine (T4)
Which compound is produced by the attachment of two iodides to tyrosine?
Monoiodotyrosine (MIT)
Triiodothyronine (T3)
Diiodotyrosine (DIT)
Tetraiodothyronine (T4)
What is the result of coupling one MIT and one DIT within the Tg molecule?
Tetraiodothyronine (T4)
Diiodotyrosine (DIT)
Monoiodotyrosine (MIT)
Triiodothyronine (T3)
Which process yields tetraiodothyronine (T4 or thyroxine)?
Coupling of one MIT and one DIT
Coupling of two DITs
Coupling of two MITs
Attachment of one iodide to tyrosine
The sequence of events that leads to the formation of T3 and T4 hormones from tyrosine within the Tg molecule involves which of the following processes?
Iodide attaches to tyrosine, forming MIT and DIT, which then couple to form T3 and T4.
MIT and DIT are formed by coupling T3 and T4.
T3 and T4 are formed by the breakdown of DIT.
Tyrosine is directly converted to T3 and T4 without iodide attachment.
Which process allows thyroid follicular cells to engulf a portion of Tg-containing colloid?
Endocytosis
Phagocytosis
Pinocytosis
Exocytosis
What is the role of lysosomes in the secretion of thyroid hormone?
They synthesize Tg
They attack the engulfed vesicle and split the iodinated product from Tg
They transport T3 and T4 into the blood
They stimulate the thyroid gland
Which thyroid hormones are freed to diffuse across the plasma membrane into the blood during secretion?
T1 and T2
T2 and T4
T3 and T4
T3 and T5
90% of the thyroid hormone released from the thyroid gland is in the form of which hormone?
T1
T2
T3
T4
Although most thyroid hormone released is T4, which form is the most biologically active?
T1
T2
T3
T4
Which disease is the most common cause of hyperthyroidism?
Addison's disease
Graves' disease
Hashimoto's disease
Cushing's syndrome
What is the role of thyroid-stimulating immunoglobulins (TSI) in Graves' disease?
They inhibit the action of TSH
They mimic the action of TSH
They destroy thyroid cells
They block thyroid hormone production
Which of the following is NOT a typical symptom of hyperthyroidism?
Decrease in body weight
Increase in heart rate
Decrease in heat production
Exaggerated reflexes
A patient presents with elevated basal metabolic rate, increased heat production, and exaggerated reflexes. Which condition do these symptoms most likely indicate?
Hypothyroidism
Hyperthyroidism
Diabetes Mellitus
Addison's disease
Graves' disease leads to an increase in heart rate and strength of contraction because:
TSI mimics TSH, increasing thyroid hormone production, which stimulates the heart
TSI inhibits TSH, reducing heart activity
TSI destroys heart muscle cells directly
TSI blocks nervous system stimulation
What is goiter?
An abnormal enlargement of the thyroid gland
A decrease in thyroid hormone production
A type of thyroid cancer
A deficiency of calcium in the blood
Which of the following can cause goiter?
Excessive stimulation of the thyroid gland by TSH or thyroid-stimulating immunoglobulins
High levels of calcium in the diet
Overproduction of insulin
Lack of vitamin D in the diet
Goiter can result from which dietary deficiency?
Lack of iodine
Lack of iron
Lack of vitamin C
Lack of potassium
Both hyperthyroidism and hypothyroidism can lead to the development of goiter because:
Hyperthyroidism causes excessive stimulation of the thyroid gland, while hypothyroidism can result from lack of iodine, both leading to thyroid enlargement.
Both conditions decrease the size of the thyroid gland.
Only hypothyroidism leads to goiter, not hyperthyroidism.
Both conditions are unrelated to thyroid gland size.
Which of the following is a primary cause of hypothyroidism?
Primary failure of thyroid gland
Excessive dietary supply of iodine
Overproduction of TRH and TSH
Increased metabolic activity
What is a common symptom of hypothyroidism related to metabolic activity?
Reduced basal metabolic rate
Increased heart rate
Rapid weight loss
Improved tolerance to cold
Which of the following is NOT a symptom of hypothyroidism?
Rapid reflexes
Slow weak pulse
Easily fatigued
Excessive weight gain
A patient presents with poor tolerance of cold, excessive weight gain, and slow mental responsiveness. Which condition do these symptoms most likely indicate?
Hypothyroidism
Hyperthyroidism
Diabetes mellitus
Cushing's syndrome
Inadequate dietary supply of iodine can lead to hypothyroidism because:
Iodine is necessary for thyroid hormone synthesis, and its deficiency impairs hormone production.
Iodine increases insulin production, which affects thyroid function.
Iodine deficiency causes overproduction of TRH and TSH.
Iodine is only important for adrenal gland function.
A possible underlying cause of slow reflexes and slow mental responsiveness in a patient with hypothyroidism is:
Reduced thyroid hormone levels decrease metabolic activity in the nervous system, leading to slow reflexes and mental responsiveness.
Increased thyroid hormone levels speed up nervous system activity.
Excessive dietary iodine causes hyperactivity of the nervous system.
Deficiency of insulin affects the nervous system.
Which condition results from hypothyroidism from birth and is characterized by physical deformity and learning difficulties?
Myxedema
Cretinism
Hyperthyroidism
Goiter
What is a common physical symptom of myxedema?
Excessive sweating
Puffy appearance of face, hands, and feet
Rapid heartbeat
Weight loss
Hypothyroidism can lead to the development of which of the following conditions, and how do their clinical presentations differ?
Cretinism results from hypothyroidism from birth causing physical and mental developmental issues, while myxedema is characterized by puffiness due to water-retaining carbohydrates in adults.
Cretinism is due to hypothyroidism in adulthood, while myxedema is due to hypothyroidism from birth; both cause weight loss.
Both cretinism and myxedema are caused by hyperthyroidism and result in increased metabolism.
Cretinism and myxedema are unrelated to thyroid hormone abnormalities.
Which of the following is the outermost layer of the adrenal cortex?
Zona glomerulosa
Zona fasciculata
Zona reticularis
Zona medullaris
What hormone is mainly secreted by the zona glomerulosa?
Cortisol
Aldosterone
Dehydroepiandrosterone (DHEA)
Adrenaline
Which layer of the adrenal cortex is responsible for secreting glucocorticoids?
Zona glomerulosa
Zona fasciculata
Zona reticularis
Zona medullaris
What is the primary function of glucocorticoids secreted by the zona fasciculata?
Influence mineral balance
Major role in glucose metabolism and adaptation to stress
Stimulate muscle contraction
Regulate heart rate
Which hormone is the most abundant and physiologically important sex hormone secreted by the zona reticularis?
Testosterone
Estrogen
Dehydroepiandrosterone (DHEA)
Progesterone
The zona reticularis of the adrenal cortex secretes hormones that are:
Identical or similar to those produced by the gonads
Only involved in glucose metabolism
Responsible for heart rate regulation
Exclusively mineralocorticoids
The adrenal cortex contributes to the body's adaptation to stress by:
Secreting glucocorticoids, which play a role in glucose metabolism and help the body respond to stress
Increasing heart rate directly
Producing only mineralocorticoids
Secreting insulin
What is the principal action site for aldosterone in the body?
Proximal tubules of the kidney
Distal and collecting tubules of the kidney
Liver cells
Adrenal medulla
Which of the following increases the secretion of aldosterone?
Decrease in plasma K+ concentration
Activation of RAAS due to a reduction in Na+ and a fall in blood pressure
Increase in blood glucose levels
Inhibition of RAAS
Aldosterone secretion is regulated largely independently of which of the following?
Posterior pituitary control
Anterior pituitary control
Thyroid gland control
Pancreatic control
Which of the following would most likely lead to an increase in aldosterone secretion?
Decrease in plasma K+ concentration
Increase in plasma K+ concentration
Increase in plasma Na+ concentration
Decrease in blood glucose concentration
A patient has a fall in blood pressure and a reduction in Na+ levels. Which physiological system is activated to increase aldosterone secretion?
Sympathetic nervous system
Renin-Angiotensin-Aldosterone System (RAAS)
Parasympathetic nervous system
Hypothalamic-pituitary-adrenal axis
What is the result of hypersecretion of adrenal androgen (DHEA)?
Feminizing condition
Masculinizing condition
Decreased body hair
Reduced muscle mass
Which of the following is a symptom of adrenogenital syndrome in adult females?
Decreased body hair
Hirsutism (increase in body hair)
Increased breast size
Higher-pitched voice
What is a likely symptom in newborn females with adrenogenital syndrome?
Smaller breasts
Male-type external genitalia
Deepening of voice
Increased sex drive
Which of the following best describes the effect of DHEA hypersecretion in adult males?
Premature development of deep voice
Hirsutism
No apparent effect
Increased breast size
A prepubertal male with DHEA hypersecretion is most likely to experience which of the following?
Decreased sex drive
Premature development of deep voice and beard
Smaller penis
Feminizing symptoms
Which of the following best describes Addison’s disease?
An autoimmune disease caused by destruction of the adrenal cortex due to erroneous production of adrenal cortex-antibodies
A genetic disorder affecting the thyroid gland
A condition caused by excessive secretion of adrenal hormones
A bacterial infection of the adrenal medulla
What is a common result of aldosterone deficiency?
Hyperkalemia and hyponatremia
Hyperglycemia and dehydration
Hypokalemia and hypernatremia
Increased blood pressure
Which of the following symptoms is associated with cortisol deficiency?
Poor response to stress and hypoglycemia
Increased appetite and weight gain
High blood pressure and tachycardia
Hypernatremia and muscle cramps
A patient presents with both hyperkalemia and hyponatremia. Which hormone deficiency is most likely responsible?
Aldosterone
Insulin
Thyroxine
Parathyroid hormone
All layers of the adrenal cortex being undersecreting leads to Addison’s disease because:
Because all hormones produced by the adrenal cortex are deficient, leading to multiple systemic effects
Because only the outer layer is affected, causing mild symptoms
Because the adrenal medulla compensates for the loss
Because the pituitary gland increases hormone production
Which hormone is secreted during the activation of the sympathetic nervous system as part of the generalized stress response?
Epinephrine
Insulin
Cortisol
Vasopressin
What is the primary function of the CRH-ACTH-cortisol system during the stress response?
Mobilizing metabolic resources to help the body cope
Increasing blood pressure only
Decreasing blood glucose levels
Stimulating insulin secretion
Which of the following changes occurs in blood composition during the stress response?
Elevation of blood glucose and fatty acids
Decrease in blood volume
Decrease in blood pressure
Increase in insulin secretion
During the stress response, which system's increased activity leads to an increase in blood volume and blood pressure?
RAAS (Renin-Angiotensin-Aldosterone System)
Digestive system
Parasympathetic nervous system
Lymphatic system
Which organ coordinates all the actions involved in the generalized stress response?
Hypothalamus
Liver
Pancreas
Adrenal medulla
The activation of the sympathetic nervous system and the CRH-ACTH-cortisol system work together to prepare the body for a stressor by:
Both systems decrease blood glucose and fatty acids.
The sympathetic nervous system prepares the body for immediate action, while the CRH-ACTH-cortisol system mobilizes metabolic resources for sustained coping.
The sympathetic nervous system increases insulin, while the CRH-ACTH-cortisol system decreases blood pressure.
Both systems only affect the digestive system.
Which of the following is a reason why nutrients must be stored in the body?
Because food intake is intermittent
Because the body cannot digest food
Because nutrients are always in excess
Because the body does not use nutrients
In which form is excess circulating glucose primarily stored in the body?
As triglycerides in adipose tissue
As glycogen in liver and muscle
As amino acids in blood
As proteins in muscle
What happens to additional glucose once liver and muscle glycogen stores are filled up?
It is excreted in urine
It is transformed into fatty acids and glycerol and stored in adipose tissue
It is converted into proteins
It is used to build muscle fibers
How are excess circulating fatty acids stored in the body?
As glucose in the liver
As triglycerides in adipose tissue
As amino acids in muscle
As glycogen in muscle
What is the fate of excess circulating amino acids in the body?
They are stored as proteins in the liver
They are converted to glucose and fatty acids, which are then stored as triglycerides
They are excreted directly
They are stored as glycogen in muscle
The body’s metabolic state influences the handling of organic molecules by:
determining whether nutrients are stored or mobilized, affecting how glucose, fatty acids, and amino acids are processed and stored.
only affecting the digestion of food.
having no effect on nutrient storage.
only affecting water absorption.
Which tissue plays a primary role in maintaining normal blood glucose levels?
Muscle
Adipose tissue
Liver
Brain
What is the principal site for metabolic interconversions such as gluconeogenesis?
Muscle
Liver
Brain
Adipose tissue
Which tissue serves as a primary energy storage site for fats?
Muscle
Liver
Adipose tissue
Brain
Why is it mandatory for blood glucose levels to be maintained for the brain?
The brain stores glycogen
The brain can use fatty acids as an energy source
The brain normally can only use glucose as an energy source and does not store glycogen
The brain is not a major energy user
