Life Processes: Communication, Homeostasis, and Energy in Living Organisms

Question 1

In a negative feedback loop, how do receptor proteins and effectors contribute to maintaining homeostasis?

Accepted Answer

Receptor proteins bind to molecules, triggering events that lead to responses carried out by effectors.

Answer

Receptor proteins detect changes and trigger responses, while effectors amplify these signals.

Answer

Receptor proteins and effectors work independently to detect changes and maintain homeostasis.

Question 2

In homeothermic organisms, how does cellular respiration contribute to maintaining a stable body temperature?

Accepted Answer

Produces heat as a byproduct, raising body temperature when needed.

Answer

Consumes glucose, lowering blood sugar levels and triggering shivering for heat generation.

Answer

Stimulates hormone release, increasing metabolic rate and heat production.

Question 3

How do organisms balance energy allocation between maintaining homeostasis and other biological functions?

Accepted Answer

Energy allocation shifts between homeostasis and other functions based on environmental conditions.

Answer

Homeostasis is always prioritized, regardless of the cost.

Answer

Organisms can invest equally in both homeostasis and other functions without trade-offs.

Question 4

In which physiological process do positive feedback mechanisms play a crucial role?

Accepted Answer

Initiation of labor during childbirth

Answer

Regulation of blood glucose levels

Answer

Body temperature maintenance

Question 5

How does hormonal communication contribute to maintaining homeostasis in multicellular organisms?

Accepted Answer

Hormones coordinate responses to maintain homeostasis by integrating signals from various sources.

Answer

Hormones enable rapid responses to stimuli, allowing organisms to react quickly to environmental changes.

Answer

Hormones act locally, targeting specific cells or tissues near their release site.

Answer

Hormones can directly alter gene expression, influencing the production of proteins and enzymes involved in homeostasis.

Question 6

Which hormone primarily regulates blood glucose levels?

Accepted Answer

Insulin

Answer

Glucagon

Answer

Thyroxine

Answer

Epinephrine

Question 7

In maintaining blood glucose homeostasis, the pancreas primarily releases:

Accepted Answer

Insulin and glucagon

Answer

Epinephrine and norepinephrine

Answer

Thyroxine and triiodothyronine

Answer

Somatotropin and prolactin

Question 8

The primary energy currency of cells is:

Accepted Answer

ATP

Answer

Glucose

Answer

Glycogen

Answer

NADH

Question 9

Photosynthesis is the process by which plants convert which form of energy?

Accepted Answer

Light

Answer

Heat

Answer

Sound

Answer

Chemical

Question 10

The final electron acceptor in cellular respiration is:

Accepted Answer

Oxygen

Answer

Water

Answer

NADH

Answer

FADH2

Question 11

Which substance acts as a neurotransmitter?

Accepted Answer

Dopamine

Answer

Glucagon

Answer

Estrogen

Answer

Testosterone

Question 12

The hypothalamus, in relation to body temperature regulation:

Accepted Answer

Detects temperature changes and triggers responses

Answer

Produces hormones that directly control temperature

Answer

Shivers to generate heat

Answer

Dilates blood vessels to release heat

Question 13

Which function is not carried out by the kidneys?

Accepted Answer

Producing red blood cells

Answer

Filtering waste products from the blood

Answer

Regulating blood pH

Answer

Secreting hormones

Question 14

The correct sequence of events in hormonal signaling is:

Accepted Answer

Receptor binding → Second messenger production → Target cell response

Answer

Target cell response → Second messenger production → Receptor binding

Answer

Second messenger production → Target cell response → Receptor binding

Answer

Receptor binding → Target cell response → Second messenger production

Question 15

Which of the following is a key characteristic of negative feedback loops in homeostasis?

Accepted Answer

They stabilize the internal environment by reversing changes from the set point.

Answer

They amplify the initial stimulus and cause the system to overshoot the set point.

Answer

They only occur in response to large changes in the internal environment.

Answer

They require an external signal to initiate the response.

Question 16

Which of the following is NOT a function of the nervous system?

Accepted Answer

Storing energy for the body

Answer

Receiving and processing sensory information

Answer

Controlling movement and muscle activity

Answer

Regulating body temperature

Question 17

The primary source of ATP production in cells is:

Accepted Answer

Oxidative phosphorylation

Answer

Glycolysis

Answer

Krebs cycle

Answer

Electron transport chain

Question 18

The main function of ribosomes in cells is:

Accepted Answer

Protein synthesis

Answer

DNA replication

Answer

RNA transcription

Answer

Lipid synthesis

Question 19

The correct sequence of stages in the cell cycle is:

Accepted Answer

Interphase → Prophase → Metaphase → Anaphase → Telophase

Answer

Interphase → Metaphase → Prophase → Anaphase → Telophase

Answer

Prophase → Interphase → Metaphase → Anaphase → Telophase

Answer

Prophase → Metaphase → Interphase → Anaphase → Telophase

Question 20

The Golgi apparatus is primarily responsible for:

Accepted Answer

Modifying, sorting, and packaging macromolecules

Answer

Protein synthesis

Answer

Lipid synthesis

Answer

DNA replication

Question 21

Homeostasis refers to the:

Accepted Answer

Maintenance of a stable internal environment

Answer

Production of hormones

Answer

Transport of nutrients

Answer

Removal of waste products

Question 22

Mitochondria are primarily responsible for:

Accepted Answer

Electron transport chain

Answer

Glycolysis

Answer

Citric acid cycle

Answer

Photosynthesis

Question 23

Endocrine glands release hormones into the:

Accepted Answer

Bloodstream

Answer

Lymph

Answer

Interstitial fluid

Answer

Stomach

Question 24

The energy currency of the cell is:

Accepted Answer

ATP

Answer

Glucose

Answer

NADH

Answer

FADH2

Question 25

Which of these is not a method of cell-to-cell communication?

Accepted Answer

Osmosis

Answer

Direct contact

Answer

Paracrine signaling

Answer

Endocrine signaling

Question 26

Which of these triggers the release of adrenaline from the adrenal glands?

Accepted Answer

Stress

Answer

Low blood sugar levels

Answer

High blood pressure

Answer

Hunger

Question 27

What is the main purpose of the respiratory system?

Accepted Answer

Exchange of gases between the blood and tissues

Answer

Regulation of body temperature

Answer

Removal of waste products

Answer

Protection from pathogens

Question 28

Which of these is an example of a negative feedback mechanism?

Accepted Answer

Regulation of blood glucose levels by insulin

Answer

Release of adrenaline in response to stress

Answer

Regulation of body temperature by sweating

Answer

Release of hormones in response to low blood pressure

Question 29

Which of these is not a function of the nervous system?

Accepted Answer

Storage of genetic information

Answer

Coordination of muscle movements

Answer

Transmission of sensory information

Answer

Regulation of body temperature

Question 30

Which hormone is secreted by the pancreas?

Accepted Answer

Insulin

Answer

Thyroxine

Answer

Growth hormone

Answer

Adrenaline

Question 31

Where in the cell does protein synthesis take place?

Accepted Answer

Ribosomes

Answer

Nucleus

Answer

Golgi apparatus

Answer

Endoplasmic reticulum

Question 32

Which process is responsible for maintaining a stable body temperature?

Accepted Answer

Thermoregulation

Answer

Osmosis

Answer

Respiration

Answer

Photosynthesis

Question 33

Which of these is a distinctive feature of eukaryotic cells?

Accepted Answer

Presence of a nucleus

Answer

Absence of membrane-bound organelles

Answer

Small size

Answer

Prokaryotic ribosomes

Question 34

In a negative feedback mechanism, the response to a stimulus:

Accepted Answer

Opposes the initial stimulus

Answer

Amplifies the initial stimulus

Answer

Remains constant regardless of the stimulus

Answer

Increases gradually over time

Question 35

The molecule that serves as the main energy currency in cells is:

Accepted Answer

ATP

Answer

Glucose

Answer

NADH

Answer

FADH2

Question 36

The process by which plants harness light energy to create chemical energy is called:

Accepted Answer

Photosynthesis

Answer

Chemosynthesis

Answer

Glycolysis

Answer

Respiration

Question 37

Which hormone plays a crucial role in controlling blood sugar levels?

Accepted Answer

Insulin

Answer

Thyroid hormone

Answer

Adrenaline

Answer

Cortisol

Question 38

The breakdown of glucose in the presence of oxygen is referred to as:

Accepted Answer

Cellular respiration

Answer

Glycolysis

Answer

Fermentation

Answer

Chemosynthesis

Question 39

A characteristic of negative feedback loops is that they:

Accepted Answer

Maintain a stable internal environment

Answer

Intensify the initial stimulus

Answer

Are rare in biological systems

Answer

Require external input to function

Question 40

The communication method used by cells to interact over long distances is known as:

Accepted Answer

Endocrine signaling

Answer

Paracrine signaling

Answer

Autocrine signaling

Answer

Juxtacrine signaling

Question 41

In eukaryotic cells, the primary site for ATP synthesis is:

Accepted Answer

Mitochondria

Answer

Cytoplasm

Answer

Chloroplasts

Answer

Ribosomes

Question 42

The breakdown of glucose in the absence of oxygen is known as:

Accepted Answer

Fermentation

Answer

Glycolysis

Answer

Cellular respiration

Answer

Chemosynthesis

Question 43

Which of the following is NOT a key function of the circulatory system?

Accepted Answer

Production of hormones

Answer

Transport of nutrients and oxygen

Answer

Regulation of body temperature

Answer

Removal of waste products

Question 44

Which hormone is responsible for lowering blood glucose levels?

Accepted Answer

Insulin

Answer

Glucagon

Answer

Testosterone

Answer

Estrogen

Question 45

Which of the following is a characteristic of a negative feedback loop in homeostasis?

Accepted Answer

The response counteracts the initial change, bringing it back to the set point.

Answer

The response amplifies the initial change, leading to a greater deviation from the set point.

Answer

The response is independent of the initial change, and does not affect the set point.

Answer

The response is triggered by an increase in the stimulus, rather than a decrease.

Question 46

Which type of chemical reaction involves the release of energy?

Accepted Answer

Exothermic

Answer

Endothermic

Answer

Neutralization

Answer

Redox

Question 47

What is the primary role of ribosomes in cells?

Accepted Answer

Protein synthesis

Answer

DNA replication

Answer

RNA transcription

Answer

Lipid metabolism

Question 48

Which of the following is NOT a stage in cellular respiration?

Accepted Answer

Lactic acid fermentation

Answer

Glycolysis

Answer

Krebs cycle

Answer

Electron transport chain

Question 49

What is the key role of enzymes in biological processes?

Accepted Answer

To speed up chemical reactions by lowering the activation energy

Answer

To provide energy for reactions

Answer

To alter the equilibrium of reactions

Answer

To produce new molecules from scratch

Question 50

Which hormone is primarily responsible for regulating blood glucose levels?

Accepted Answer

Insulin

Answer

Estrogen

Answer

Testosterone

Answer

Cortisol

Question 51

The process of maintaining a stable internal environment despite external changes is known as:

Accepted Answer

Homeostasis

Answer

Allostasis

Answer

Thermoregulation

Answer

Osmoregulation

Question 52

The primary function of ATP in energy metabolism is to:

Accepted Answer

Act as a short-term energy storage molecule

Answer

Transfer electrons in the electron transport chain

Answer

Synthesize proteins

Answer

Split water molecules in photosynthesis

Question 53

The final electron acceptor in cellular respiration is:

Accepted Answer

Oxygen

Answer

NADH

Answer

FADH2

Answer

Carbon dioxide

Question 54

The process by which plants convert light energy into chemical energy is known as:

Accepted Answer

Photosynthesis

Answer

Cellular respiration

Answer

Glycolysis

Answer

Krebs cycle

Question 55

Which hormone, produced by the pituitary gland, stimulates the adrenal cortex to release hormones?

Accepted Answer

Adrenocorticotropic hormone (ACTH)

Answer

Antidiuretic hormone (ADH)

Answer

Follicle-stimulating hormone (FSH)

Answer

Luteinizing hormone (LH)

Question 56

Which hormone is responsible for regulating blood glucose levels?

Accepted Answer

Insulin

Answer

Epinephrine

Answer

Cortisol

Answer

Thyroxine

Question 57

What is the primary function of a negative feedback loop in homeostasis?

Accepted Answer

To maintain a stable internal environment

Answer

To amplify physiological responses

Answer

To trigger the release of hormones

Answer

To inhibit cellular processes

Question 58

Which of the following is NOT a component of the human respiratory system?

Accepted Answer

Liver

Answer

Lungs

Answer

Trachea

Answer

Diaphragm

Question 59

What is the main energy currency of cells?

Accepted Answer

ATP

Answer

Glucose

Answer

Oxygen

Answer

Carbon dioxide

Question 60

Which stage of cellular respiration releases the most energy?

Accepted Answer

Electron transport chain

Answer

Glycolysis

Answer

Krebs cycle

Answer

Beta-oxidation

Question 61

What is the difference between a first messenger and a second messenger in signal transduction?

Accepted Answer

First messengers are ligands that bind to receptors, while second messengers are intracellular molecules that relay the signal.

Answer

First messengers are intracellular molecules that relay the signal, while second messengers are ligands that bind to receptors.

Answer

Both first and second messengers are ligands that bind to receptors.

Answer

Both first and second messengers are intracellular molecules that relay the signal.

Question 62

Which of the following is NOT a characteristic of an effective homeostatic control system?

Accepted Answer

Amplification

Answer

Sensitivity

Answer

Stability

Answer

Precision

Question 63

What is the primary role of the nervous system in communication?

Accepted Answer

To transmit electrical and chemical signals throughout the body

Answer

To regulate body temperature

Answer

To produce hormones

Answer

To digest food

Question 64

Which of the following represents the correct sequence of energy flow in an ecosystem?

Accepted Answer

Sunlight -> Plants -> Animals -> Decomposers

Answer

Sunlight -> Decomposers -> Plants -> Animals

Answer

Animals -> Plants -> Sunlight -> Decomposers

Answer

Decomposers -> Animals -> Sunlight -> Plants