Animal Physiology 1

What is homeostasis?

The process by which living organisms regulate their internal environment to maintain stable, constant conditions despite external changes.

Define metabolism.

The sum of all chemical reactions that occur within an organism to maintain life, including catabolism and anabolism.

What are phospholipids?

Amphipathic molecules that possess both hydrophilic (polar) and hydrophobic (nonpolar) regions, crucial for forming cell membranes.

What role does cholesterol play in cell membranes?

helps stabilize the membrane's fluidity and prevents fatty acid chains of phospholipids from packing too closely together.

What are glycolipids?

Molecules that make up approximately 5% of the lipids in the cell membrane and play significant roles in cell recognition and signaling.

What are integral proteins?

Proteins that span the entire membrane and are often involved in functions such as channels or transporters.

Define facilitated diffusion.

A passive transport mechanism that involves specific transporter proteins to move molecules across the membrane down their concentration gradient.

What is the sodium-potassium pump?

A primary active transport mechanism that expels Na+ ions from the cell while bringing K+ ions in, crucial for maintaining cellular ion balance.

What are tight junctions?

Type of cell junctions that seal adjacent epithelial cells to regulate permeability and force substances to enter cells selectively.

Describe osmotic pressure.

the concentration of solute particles that cannot cross the membrane, influencing cell volume and pressure.

What is the process of keratinization?

The process involving the accumulation of keratin as cells move from the stratum basale to the surface, undergoing apoptosis.

What do melanocytes do?

These cells in the basal layer of the epidermis are responsible for synthesizing melanin, influencing skin color.

What is the function of intercalated discs in cardiac muscle?

They connect adjacent cardiac muscle cells, allowing for synchronized contractions.

What are synapses?

Connections between neurons where information is transmitted, classified as electrical or chemical.

What is the final common pathway in blood clotting?

Involves positive feedback from thrombin, which accelerates the formation of prothrombinase and activates platelets for effective clot formation.

How do action potentials propagate in neurons?

They involve rapid changes in membrane potential, primarily driven by Na+ and K+ voltage-gated channels.

What is the primary function of the respiratory system?

To facilitate gas exchange, intake of oxygen, and expulsion of carbon dioxide.

How is cardiac output (CO) calculated?

stroke volume (SV) times heart rate (HR): CO = SV x HR.

What is the role of tubular secretion in the renal system?

Involves the movement of substances from the blood into the nephron's filtrate to regulate pH and waste elimination.

What is the significance of myelin in neural communication?

insulates axons and facilitates rapid transmission of electrical signals between neurons.

What are the primary types of muscle tissue?

Skeletal, cardiac, and smooth muscle, each with distinct structures and functions.

Differentiate between rough ER and smooth ER.

Rough ER is studded with ribosomes and synthesizes proteins, while smooth ER is involved in lipid synthesis and detoxification.

What is the role of the Golgi apparatus?

modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

What is apoptosis?

The programmed cell death process that eliminates damaged or unnecessary cells without causing an inflammatory response.

Define stem cells.

Undifferentiated cells with the potential to develop into various cell types or self-renew indefinitely.

What is the significance of cell signaling?

regulates cellular activities and allows cells to communicate, respond to their environment, and coordinate responses.

Explain what an enzyme is.

biological catalysts that accelerate chemical reactions without being consumed in the process.

What factors influence enzyme activity?

Temperature, pH, substrate concentration, and the presence of inhibitors or activators can all affect enzyme function.

What is feedback inhibition?

A regulatory mechanism where the end product of a metabolic pathway inhibits an earlier step to prevent overproduction.

What is the function of DNA?

stores genetic information that guides the development, functioning, growth, and reproduction of all living organisms.

Describe the structure of DNA.

two strands forming a double helix, consisting of nucleotides containing a sugar, phosphate group, and nitrogenous base.

What are complementary base pairs in DNA?

Pairs of nitrogenous bases that bond; adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G).

What is the function of RNA?

transcribes and translates the genetic information from DNA to synthesize proteins.

Define transcription.

The process by which messenger RNA (mRNA) is synthesized from a DNA template.

Explain translation.

The process by which ribosomes synthesize proteins by decoding the mRNA sequence.

What are mutations?

Changes in the DNA sequence that can lead to variations in traits; they can be beneficial, harmful, or neutral.

What is the cell cycle?

The series of steps that a cell goes through to grow and divide, consisting of interphase and the mitotic phase.

Describe mitosis.

The process of nuclear division in which one cell divides to produce two genetically identical daughter cells.

What is meiosis?

A specialized form of cell division that reduces the chromosome number by half and leads to the formation of gametes.

What is the role of the plasma membrane?

regulates the movement of substances in and out of the cell, maintaining homeostasis.

Define endocytosis and exocytosis.

Endocytosis is the process of taking substances into the cell, while exocytosis is the process of expelling substances from the cell.

What are chemical messengers?

Molecules such as hormones or neurotransmitters that transmit signals between cells and coordinate physiological processes.

What is the difference between active and passive transport?

Active transport requires energy to move substances against their concentration gradient, while passive transport moves substances down their gradient without energy.

Define the term ‘gene’.

unit of heredity that consists of a sequence of DNA coding for a specific protein or trait.

What is a chromosome?

a long strand of DNA wrapped around proteins, containing many genes.

What is the purpose of the cell wall in plant cells?

provides structural support, protection, and helps to maintain the shape of plant cells.

Explain the role of chloroplasts in plant cells.

organelles that conduct photosynthesis, converting light energy into chemical energy stored as glucose.

What is photosynthesis?

The process by which green plants convert carbon dioxide and water into glucose and oxygen using sunlight.

Define cellular respiration in simple terms.

how cells convert glucose and oxygen into energy (ATP), carbon dioxide, and water.

What is ATP?

primary energy carrier in cells, providing energy for various cellular processes.

What are the phases of cellular respiration?

The three phases are glycolysis, the Krebs cycle, and electron transport chain.

What is glycolysis?

The metabolic process that breaks down glucose to produce ATP, occurring in the cytoplasm.

Describe the Krebs cycle.

A series of enzyme-catalyzed chemical reactions that generate energy through the oxidation of acetyl-CoA.

What is oxidative phosphorylation?

The final stage of cellular respiration where ATP is produced in the presence of oxygen during the electron transport chain.

What is the function of mitochondria?

powerhouse of the cell, responsible for producing ATP through cellular respiration.

Define homeostasis in simple terms.

ability of an organism to maintain a stable internal environment despite external changes.

What are the basic functions of the nervous system?

To receive stimuli, process information, and coordinate responses throughout the body.

What is a neurotransmitter?

Chemicals that transmit signals across synapses between neurons and other cells.

What is an action potential?

A rapid rise and subsequent fall in voltage or membrane potential across a cellular membrane.

What are the roles of sensory neurons?

transmit sensory information from receptors to the central nervous system (CNS).

Define motor neurons.

transmit signals from the CNS to muscles or glands, facilitating movement and action.

What is the function of the autonomic nervous system?

regulates involuntary bodily functions such as heart rate, digestion, and respiratory rate.

What is the somatic nervous system?

controls voluntary movements and transmits sensory information to the CNS.

What is a reflex arc?

The neural pathway that mediates a reflex action, allowing an immediate response to a stimulus.

What is the function of the endocrine system?

regulates bodily functions through hormones that are secreted into the bloodstream.

What is the role of hormones?

Chemical messengers that help regulate processes such as growth, metabolism, and mood.

Describe the function of the immune system.

protects the body from infections and diseases through a complex network of cells, tissues, and organs.

What are antibodies?

Proteins produced by the immune system that specifically target and neutralize pathogens.

What is an antigen?

A substance that induces an immune response, often recognized by antibodies as foreign.

What is the significance of vaccination?

stimulates the immune system to develop immunity to a disease without causing the disease itself.

What is innate immunity?

non-specific first line of defense that the body has against pathogens.

What is adaptive immunity?

immune response that develops over time, often through exposure to pathogens.

What is the primary role of red blood cells?

transport oxygen from the lungs to the body's tissues and carry carbon dioxide back to the lungs.

What is hemoglobin?

A protein in red blood cells that binds to oxygen and carries it throughout the body.

Define the structure of the heart.

four chambers: two atria and two ventricles, which pump blood through the circulatory system.

What is blood pressure?

force exerted by circulating blood on the walls of blood vessels.

What is the role of platelets?

cell fragments involved in the blood clotting process to prevent excessive bleeding.

Explain the difference between arteries and veins.

Arteries carry blood away from the heart, while veins bring blood back to the heart.

What is the function of the lymphatic system?

maintain fluid balance, absorb fats, and provide immune responses.

What are the primary functions of the urinary system?

regulates fluid balance, excretes waste products, and helps maintain electrolyte levels.

What is the role of the kidneys?

filter blood, remove waste, and regulate fluid and electrolyte balance.

Define nephron.

functional unit of the kidney that filters blood and produces urine.

What is urine composed of?

water, urea, creatinine, and various ions and molecules.

What is the function of the gastrointestinal system?

responsible for the digestion and absorption of nutrients and the elimination of waste.

What is the role of the liver in digestion?

produces bile, which aids in the digestion and absorption of fats, and processes nutrients from the digestive system.

What is the function of enzymes in digestion?

break down food into smaller, absorbable molecules.

What are the main types of nutrients?

carbohydrates, proteins, fats, vitamins, and minerals.

What is metabolism?

encompasses all chemical reactions that occur within an organism to maintain life.

Describe the role of vitamins in the body.

organic compounds that are essential for various metabolic processes and overall health.

What is the role of minerals in the body?

inorganic nutrients that support various bodily functions, including bone health, fluid balance, and muscle contractions.

What is the role of ribosomes in a cell?

molecular machines that synthesize proteins by translating messenger RNA (mRNA) sequences.

What is the primary function of lysosomes?

contain digestive enzymes that break down waste materials and cellular debris.

What is the difference between prokaryotic and eukaryotic cells?

Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have a nucleus and organelles.

What is osmosis?

movement of water across a selectively permeable membrane from an area of lower solute concentration to higher solute concentration.

What is active transport?

process of moving substances across a cell membrane against their concentration gradient, requiring energy.

What are the two main types of nucleic acids?

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).

What is the function of the rough endoplasmic reticulum (rough ER)?

involved in the synthesis and packaging of proteins due to its ribosome-studded surface.

What is the role of smooth endoplasmic reticulum (smooth ER)?

responsible for lipid synthesis, detoxification, and calcium ion storage.

What is the importance of cell differentiation?

allows for the specialization of cells to perform unique functions within an organism.

What are stem cells?

undifferentiated cells capable of giving rise to various cell types.