Chapter 1: Animal Anatomy and Physiology

What is homeostasis?

The maintenance of stable internal conditions.

For example, the hypothalamus regulates functions like body temperature and fluid balance, and the sympathetic and parasympathetic nervous systems work together to maintain it

What is a eukaryote?

A cell that has a membrane-bound nucleus and contains many different membrane-bound organelles. All multicellular organisms are composed of eukaryotic cells

What are the three major parts of eukaryotic cells?

The cell membrane, cytoplasm, and nucleus

What is the function of the cell membrane?

It separates the cell from its external environment and is semipermeable, allowing various substances to move in and out of the cell

What is the "powerhouse" of the cell and its main product?

Mitochondria.

It produces ATP (adenosine triphosphate) through cellular respiration

What is the function of ribosomes?

They are the site of protein synthesis

Distinguish between Rough Endoplasmic Reticulum (RER) and Smooth Endoplasmic Reticulum (SER).

RER: A hollow system of flattened membranous channels with attached ribosomes that acts as a transportation network for proteins.

SER: A hollow system of flattened membranous channels without attached ribosomes important in synthesizing cholesterol, steroid-based hormones, and lipids, as well as detoxification of drugs, breakdown of glycogen, and transportation of fats

What is the function of the Golgi complex?

Functions as a receiving, packaging, and distribution center, modifies and synthesizes carbohydrate portions of glycoproteins, and packages substances from the ER for export or internal use. It also produces lysosomes

What is the function of the nucleus?

It is the control center of the cell and contains DNA, which governs heredity and protein synthesis

diffusion

The movement of molecules (e.g., water and ions) from a high concentration to a low concentration. Oxygen enters and carbon dioxide exits a cell by simple diffusion.

Define osmosis and osmotic pressure.

Osmosis: The movement of water through a semipermeable membrane from a region of low solute concentration (high solvent) to a region of high solute concentration (low solvent).

Osmotic pressure: The amount of pressure necessary to stop the flow of water across the membrane

Define hypotonic solutions regarding RBC's.

Extracellular fluid is less concentrated than intracellular fluid; RBCs gain water and burst (hemolysis)

Define hypertonic solutions regarding RBC's.

Extracellular fluid is more concentrated than intracellular fluid. RBCs lose water and crenate (shrivel).

Define isotonic solutions regarding RBC's.

Concentrations of extracellular and intracellular fluids are equal; RBCs remain unchanged

What is active transport?

The movement of molecules from a low concentration to a high concentration with the aid of carrier proteins, requiring energy.

The sodium-potassium pump is an example.

What is endocytosis?

the process by which materials are taken into the cell.

What are the two types of endocytosis?

Phagocytosis (cell eating) and pinocytosis (cell drinking).

What is exocytosis?

Exocytosis is the process by which materials are expelled by a cell.

List the four primary types of body tissue.

Epithelial, Connective, Muscle, and Nervous

What are the main functions of epithelial tissue?

Protection, secretion, excretion, filtration, absorption of nutrients, and receipt of sensory information. It covers body surfaces, lines body cavities, and forms glands.

Distinguish between endocrine and exocrine glands.

Endocrine glands: Are ductless and secrete hormones directly into the bloodstream (ex. estrogen from ovaries).

Exocrine glands: Have ducts and secrete onto an epithelial surface (ex. sweat glands)

Describe skeletal muscle tissue.

Skeletal (striated): Voluntary control, long, parallel striated fibers with multiple peripheral nuclei; attaches to and moves bones.

Describe smooth muscle tissue.

Smooth (visceral, nonstriated): Involuntary control, spindle-shaped, smooth cells with a centrally located nucleus; found in walls of hollow organs (e.g., digestive tract, blood vessels).

Describe cardiac muscle tissue.

Cardiac (myocardium): Involuntary control, long, striated cells joined by intercalated discs; has a single, centrally located nucleus; found only in the heart

What are the two major cell types in nervous tissue?

Neurons (which conduct impulses) and neuroglial (glial) cells (which are supporting cells and do not conduct impulses).

What are the three types of membranes in the body?

Mucous membranes (mucosae), Serous membranes (serosa), and Cutaneous membranes (integument or skin).

What is the function of mucous membranes?

They line cavities that ultimately connect to the exterior of the body and are adapted to absorb and secrete, normally secreting mucus to lubricate pathways.

Cranial:

Toward the head.

Caudal:

Toward the tail.

Dorsal:

Toward the backbone.

Ventral:

Away from the backbone

Proximal:

The point closest to the backbone.

Distal:

The point farthest from the backbone

Palmar:

The bottom of the front foot.

Plantar:

The bottom of the rear foot

What are the five functions of bones?

They support soft tissues, protect vital organs, act as levers for muscle attachment, store minerals, and produce blood cells.

Define osteoblast.

Immature bone cell that produces the bone matrix (osteoid).

Define Osteocyte.

A mature bone cell.

Define Osteoclast.

A very large multinucleated cell capable of dissolving bone matrix (osteolysis or resorption).

What are the three classifications of joints (articulations) by function?

Synarthrosis: Immovable joint (ex. skull sutures).

Amphiarthrosis: Slightly movable joint (ex. pubic symphysis).

Diarthrosis: Freely movable joint (ex. stifle).

What are the three functions of muscles?

Produces movement, maintains posture, and produces heat.

What is the functional unit of skeletal muscle?

A sarcomere

What is the "all-or-none principle" in muscle contraction?

Muscle fibers either contract to their fullest or not at all.

What makes up the Central Nervous System (CNS)?

The brain and spinal cord.

What makes up the Peripheral Nervous System (PNS)?

All nerves connecting to the CNS, including all cranial and spinal nerves.

What is the primary function of the cerebrum?

It is the site of motor control, interpretation of sensory impulses, and areas of association.

What are the key functions of the thalamus?

Acts as a relay station for sensory impulses and interprets some sensations, such as temperature and pain.

What are the key functions of the hypothalamus?

Regulates many homeostatic functions (ex. body temperature, fluid balance, thirst, urine output, food intake, emotion, and behavioral patterns) and has an important connection with the endocrine system

What is the cerebellum responsible for?

Coordination and balance.

Distinguish between afferent (sensory) and efferent (motor) nerves.

Afferent: Carry impulses from sensory receptors to the CNS.

Efferent: Carry impulses from the CNS to skeletal muscle (somatic division) or smooth muscle, glands, and heart (autonomic system)

What are the two divisions of the autonomic nervous system and their primary responses?

Sympathetic: Elicits the "fight-or-flight" response (e.g., increased heart rate, respiratory rate, and blood flow) by releasing norepinephrine.

Parasympathetic: Responsible for quiet activities (e.g., digestion, heart rate) and returns the body to normal levels by releasing acetylcholine

What is the function of the heart?

Provides the force to circulate blood to all parts of the body.

What are the protective layers of the heart?

The pericardium (a double-walled membranous sac covering the myocardium, containing pericardial fluid to reduce friction)

The endocardium (a serous membrane lining the inner chambers)

What are the three main events of the cardiac cycle represented on an ECG?

P wave: Represents the electrical events during atrial systole (depolarization).

QRS complex: Represents the electrical events of ventricular systole (depolarization).

T wave: Represents the electrical events during ventricular diastole (repolarization)

Distinguish between arteries and veins.

Arteries: Carry blood away from the heart (mostly oxygenated, except pulmonary artery); are thicker and stronger than veins; have greater pressure.

Veins: Carry blood back to the heart (mostly deoxygenated); are larger than arteries and have thinner walls; have low pressure and valves to prevent backflow

Where does the exchange of oxygen and carbon dioxide take place in the circulatory system?

In the capillaries.

List the five basic processes of the digestive system.

Ingestion, mechanical and chemical digestion, peristalsis, absorption, and defecation

What are the four compartments of a ruminant stomach?

Rumen, Reticulum, Omasum, and Abomasum.

What is the major site of digestion and absorption?

The small intestine.

What are the key pancreatic enzymes and their functions?

Trypsin (digests proteins), Lipase (digests fat), and Amylase (digests starch).

What are the four functions of the lymphatic system?

Absorbs protein-containing fluid that escapes from capillaries and returns it to the venous system, transports fats from the digestive tract to blood, produces lymphocytes, and develops immunity.

What are the three basic processes of respiration in mammals?

Ventilation, External respiration (exchange of gases between alveoli and blood), and Internal respiration (exchange of gases between blood and cells).

What is the main function of the alveoli?

Microscopic air sacs where the exchange of oxygen and carbon dioxide takes place. GAS EXCHANGE.

Define tidal volume, residual volume, and dead space.

Tidal volume: The volume of air exchanged during normal breathing.

Residual volume: Air remaining in the lungs after a forced expiration.

Dead space: Air in the pathways of the respiratory system.

Define eupnea.

Normal quiet respiration.

Define dyspnea

Difficult breathing

Define apnea.

No breathing.

What is the primary chemical factor that controls respiratory rate?

An increase of carbon dioxide results in an increase in respiratory effort.

What is the microscopic unit of the kidney?

The nephron.

List the three phases of urine production.

Filtration, Reabsorption, and Secretion.

What is the function of Antidiuretic Hormone (ADH) in the kidney?

An increase in ADH release increases the reabsorption of water within the kidney.

What is the function of Aldosterone in the kidney?

Stimulates sodium reabsorption in the kidney.

What are the primary functions of the testicles?

Seminiferous tubules produce sperm, and Interstitial cells of Leydig produce testosterone

What is the function of the epididymis?

Provides storage for sperm and a place for maturation.

What hormones influence spermatogenesis and testosterone production?

Follicle-stimulating hormone (FSH) causes spermatogenesis

Interstitial cell-stimulating hormone (ICSH) causes Leydig cells to produce testosterone

What are the primary functions of the ovaries?

They produce ova and hormones.

Distinguish between uniparous and multiparous animals.

Uniparous: Giving birth to one offspring at a time (young develop in the body of the uterus).

Multiparous: Giving birth to more than one offspring at a time (ex, dogs and cats, young develop in uterine horns).

What is the difference between spontaneous ovulators and nonspontaneous (induced) ovulators?

Spontaneous ovulators: Ovulation occurs naturally regardless of coitus (dog, cattle, horse).

Nonspontaneous (induced) ovulators: Ovulate after being bred (cat, rabbit, ferret, llama, alpaca).

What are the three stages of parturition?

Stage 1: Uterine contractions begin (under the influence of oxytocin).

Stage 2: Delivery of fetus.

Stage 3: Delivery of placenta (afterbirth)

What is colostrum and why is it important for neonates?

The first milk, which contains antibodies, proteins, and vitamins, making it important for the neonate.

What hormones influence milk production (lactation) and milk letdown?

Prolactin influences milk production; Oxytocin influences milk letdown.

What are endocrine glands?

Ductless glands that produce hormones secreted directly into the bloodstream to have a specific effect on a target area.

How is hormone secretion most commonly regulated?

Through a negative feedback system; as hormone levels rise, their secretion is inhibited.

What are the two main layers of the skin and the underlying layer?

The epidermis (superficial layer) and the dermis, with the hypodermis (subcutaneous layer) underlying the dermis.

What are the functions of the skin?

It acts as a protective barrier, a sense organ, and a site for vitamin D synthesis.

What are melanocytes?

Pigment cells in the stratum germinativum of the epidermis that produce melanin, giving skin its color.

What are the three main layers (tunics) of the eye?

The sclera (outermost fibrous layer)

the uvea (middle vascular layer, including iris, ciliary body, and choroid)

the retina (innermost, light-sensitive layer housing photoreceptors)

What are rods and cones in the retina?

They are photoreceptors.

Rods: Respond to dim light (more are present in nocturnal animals).

Cones: Respond to bright light and color.

What are the three regions of the ear?

The outer ear (from pinna to tympanic membrane)

the middle ear (houses ossicles: malleus, incus, stapes)

the inner ear (houses cochlea, vestibule, and semicircular canals).

Where are hearing receptors (organ of Corti) located?

In the cochlea of the inner ear.

Where are taste receptors located?

Enclosed in gustatory papillae on the tongue.