HESI A2 A&P Test 2026/2027 | Complete Practice Exam | Verified Q&A | Latest Updated Version

HESI A2 A&P Test 2026/2027 | Complete Practice Exam | Verified Q&A | Latest Updated Version Q: Tissue Answer Group of cells that work together to perform specific functions Q: 4 tissue types & function Answer Epithelial: cover, line, and protect the body and its internal organs Connective: the framework of the body, providing support and structure for the organs. Nerve: composed of neurons and connective tissue cells that are referred to as neuroglia Muscle: has the ability to contract or shorten. It is classified as voluntary muscle (skeletal muscles) or involuntary muscle (smooth muscle and cardiac muscle) Q: Explain Mitosis Answer Essential for growth and repair. In this process DNA is duplicated and distributed evenly to two caught cells Q: Explain Meiosis Answer The special cell division that takes place in the gonads, that is, the ovaries and testes. In the process of meiosis, the chromosome number is reduced from 46 to 23, so when the egg and sperm unite in fertilization the zygote will have the correct number of chromosomes. Q: Functions of the Skeletal system (7) Answer 1. Support 2. Movement 3. Blood cell formation (hemopoiesis) 4. Protection of internal organs 5. Detoxification (removal of poisons) 6. Provision for muscle attachment 7. Mineral storage (particularly Ca2+ and phosphorus) Q: The body framework consists of (4) Answer 1. Bone 2. Cartilage 3. Ligaments 4. Joints Q: Individual bones are classified by shape: 5 Answer 1. Long bones 2. Short bones 3. Flat bones 4. Irregular bones 5. Sesamoid bones Q: Osteoblasts Answer Cells that form compact bone. When they become fixed in the dense bone matrix, they stop dividing but continue to maintain bone tissue as osteocytes Q: Axial Skeleton Answer Consists of the 28 bones of the skull, which are then separated into: 14 facial bones and 14 bones of the cranium, 33 bones of the vertebral column, Bones of the thorax, the sternum, and 12 pairs of ribs Q: Axial Skeleton: 14 Facial bones Answer 2 Nasal bones 2 Maxillary bones 2 zygomatic bones 1 mandible (only movable bone of the skull) 2 palatine bones 1 vomer 2 lacrimal bones 2 inferior nasal conchae Q: Axial Skeleton: 14 Cranial bones Answer 1. Occipital 2. Frontal 3. Ethmoid 4. Sphenoid 5. (2) Parietal 6. (2) Temporal 7. (3) Ossicles of the ear (malleus, incus, and stapes) Q: Axial Skeleton: 33 Bones of the Vertebral Column Answer 7 Cervical vertebrae 12 Thoracic vertebrae 5 lumbar vertebrae 5 sacral vertebrae (fused together to form the sacrum) Coccygeal vertebrae (known as the tailbone) Q: Epidermis Answer The outermost protective protective layer of dead keratinized epithelial cells As the epidermal cells move away from the deepest layers to the superficial layers, they move away from their blood and nutrient supply; subsequently, they dehydrate and die. Q: Dermis Answer (Inner layer) The underlying layer of fibrous connective tissue with blood vessels, sensory nerve endings, hair follicles, glands, and associated skin structures. It rests on the subcutaneous (adipose) tissue (hypodermis) that connects the skin to the superficial muscles Q: Name the layers of the Epidermis from outer layer to inner layer Answer 1. Stratum corneum 2. Stratum lucidum 3. Stratum granulosum 4. Inner most stratum germinativum (which includes the stratum basale and stratum spinosum) Q: What layer of the Epidermis does Mitosis take place Answer The inner most stratum germinative (which includes the stratum basale and stratum spinosum) Q: What cells contain melanin Answer Epidermal cells contain the protein pigment called melanin, which protects against the radiation from the sun Q: Name the two types of sweat glands Answer Eccrine: Most widely distributed sweat gland, regulates body temperature by releasing a watery secretion that evaporates from the surface of the skin Apocrine: Mainly in armpits and groin area, display apocrine secretion. This secretion contains bits of cytoplasm from the secreting cells. This cell debris attracts bacteria, and the presence of body odor occurs. Q: Sebaceous Glands Answer Release an oily secretion (sebum) through the hair follicles that lubricates the skin and prevents drying. Oil is produced by Holocrine secretion in which the whole cells of the gland are part of the secretion. These glands are susceptible to becoming clogged and attracting bacteria, particularly in during adolescence. Q: Appendages of skin (2) Answer Hair and Nails: Both are composed of a strong protein called keratin Q: Appendicular Skeleton includes the Answer Girdle and limbs Q: What must be present for a muscle cell to contract? Answer Ca2+ and Adenosine Triphosphate (ATP) Muscles produce movement by Answer Contracting in response to nervous stimulation Muscle contraction results from Answer the sliding together of actin and myosin filaments within the muscle cell or fiber Process of muscle contraction Answer Nervous stimulation from motor neurons causes the release of Ca2+ ions from the sarcoplasmic reticulum. Ca2+ ions attach to inhibitory proteins on the actin filaments within the cell, moving them aside so that cross-bridges can from between actin and myosin filaments. Using energy supplied by ATP, the filaments slide together to produce contraction Skeletal muscles, which make up the muscular system, are also called voluntary muscles because Answer they are under conscious control Explain why skeletal muscles must work in pairs and how they do so Answer The muscle that executes a given movement is the prime mover, whereas the muscle that produces the opposite movement is the antagonist. What are muscles called that work in cooperation with the prime mover? Synergists What do Flexors do reduce the angle at the joint What do extensors do Increase the angle at the joint What do abductors/adductors do Draw a limb away from the midline, and adductors return the limb back toward the body What does the nervous system consist of? Brain, spinal cord, and nerves What does the nervous system do? (3 main) 1. Enables us to perceive many of the changes that take place in our external and internal environment and to respond to those changes (seeing, hearing, tasting, smelling, and touching are examples of perception). 2. It enables us to think, reason, remember, and carry out other abstract activities. It makes body movements by skeletal muscles possible by supplying them with nerve impulses that cause contraction. 3. It works closely with the endocrine glands, correlating and integrating body functions such as digestion and reproduction What do ALL actions of the nervous system depend on? Transmission of nerve impulses over neurons, or nerve cells, the functional units of the nervous system. What are the main parts of a neuron and functions? (3) 1. Dendrites: transmit the impulse toward the cell body 2. Axons: transmit the impulse away from the cell body. 3. Body What can two things can the CNS be divided into? CNS and PNS What does the PNS consist of? ALL the nerves that transmit information to and from the CNS Sensory (afferent) neurons transmit nerve impulses toward the CNS Motor (efferent) neurons transmit nerve impulses away from the CNS toward the effector organs such as muscles, glands, and digestive organs What are the major parts of the brain 1. Cerebrum: Associated with movement and sensory input 2. Cerebellum: Responsible for muscular coordination 3. Medulla Oblongata: Controls many vital functions such as respiration and HR How long is the spinal cord? It extends from to 18 inches long; extends from the base of the skull (foramen magnum) to the first or second lumbar vertebrae (L1 or L2) How many pairs of spinal nerves exit the spinal cord? 31 What are simple (spinal) reflexes? They are those in which nerve impulses travel through the spinal cord only and do not reach the brain. Most reflex pathways involve impulses traveling to and from the brain in ascending and descending tracts of the spinal cord. Sensory Impulses enter the dorsal horns of the spinal cord, and motor impulses leave through the central horns of the spinal cord. What does the endocrine system do? (3) Assists the nervous system in homeostasis and plays important roles in growth and sexual maturation. The nervous system and endocrine system meet at the hypothalamus and pituitary gland The hypothalamus governs and is in turn controlled by the pituitary gland; the feedback of hormones in the blood List the major endocrine glands: 10 Pineal, Parathyroids, Thymus, Testes, Ovaries, Pancreas, Adrenals, Thyroid, Pituitary, Hypothalamus What are hormones and what do they do? They are chemical messengers that control the growth, differentiation, and metabolism of specific target cells What are the 2 major types of hormones and their functions? Steroid and non-steroid hormones. Steroid hormones enter the target cells and have a direct effect on the DNA of the nucleus. Some non-steroid hormones are protein hormones. Many protein hormones remain at the cell surface and act through a second messenger, usually a substance called adenosine monophosphate (AMP) How do hormones affect cell activity? By altering the rate of protein synthesis What other organs (outside of the endocrine ones) produce hormones? (3) Stomach, small intestine, and Kidneys What does the cortisol released from the adrenal cortex do? reduces inflammation, raises blood sugar level, and inhibits the release of histamine What is the master gland? The pituitary gland The pituitary gland is attached to the by a hypothalamus; by a stalk called the infundibulum What are the 2 portions of the pituitary gland and what type of hormone does each portion secrete? The anterior lobe (adenohypophysis): hormones of the anterior lobe are called "tropic hormones" because they act mainly on other endocrine glands The include: -Somatotropin Hormone (STH) or growth hormone (GH) - Adenocorticotropic hormone (ACTH) - Thyroid-stimulating hormone (TSH) - Follicle-stimulating hormone (FSH) - Luteinizing hormone (LH) The posterior lobe (neurohypophysis): hormones released from here include: - oxytocin (labor hormone) - and antidiuretic hormone (ADH) Whole blood consists of % and % 55% plasma; 45% formed elements such as erythrocytes (RBC), leukocytes (WBC), and platelets. All of the formed elements are produced from stem cells in red bone marrow. The 5 types of WBC's are / and can be distinguished on the basis of (4) 1. Macrophages 2. Neutrophils: microphages (phagocytosis) 3. Eosinophils: specialized immune cells for parasites 4. Basophils: release histamine - 911 Call for help 5. Platelets: Blood clotting 6. Lymphocytes: Acquired immunity (antibody formation) B-Cells- identify foreign invaders and produce antibodies against T-Cells- Target and destroy antibody detected cells They can be distinguished on the basis of size, appearance of the nucleus, staining properties, and the presence or absence of visible cytoplasmic granules. What does blood do Transport O2 and nutrients to body cells and carry away Co2 and metabolic wastes Plasma contains approx 10% (5) Proteins, ions, nutrients, waste products, and hormones which are dissolved and suspended in water. Blood is sent to the lungs for oxygenation through the and to the remainder of the body through the pulmonary circuit; systemic circuit Where are semilunar valves found? At the entrances of the pulmonary trunk and the aorta Blood is supplied to the myocardium by the coronary arteries Blood drains from the myocardium directly into the Right atrium through the coronary sinus. What happens at the capillaries? Exchange s take place between the blood and surrounding tissues, exchanging water, nutrients, and waste products. Describe the walls of the arteries They are thick and elastic and carry blood under high pressure. Describe the walls of veins They are thinner and less elastic than those of the arteries and carry blood under low pressure Vasoconstriction/Vasodilation influence (2) BP and blood distribution to the tissues The heart has an beat initiated by the and transmitted along a conduction system through the myocardium intrinsic; SA node -- that wave is what is measured on an ECG (EKG) What does an ECG measure NOT the diastole and systole but the electrical activity the precedes the contraction-relaxation events of the myocardium What are the components of the Respiratory system? (8) 1. Nose 2. Pharynx 3. Larynx 4. Trachea 5. Bronchi 6. lungs with their alveoli 7. Diaphragm 8. Muscles surrounding the ribs What is respiration controlled by? The respiratory control center in the medulla of the brain Explain External Respiration The exchange of gases between the atmosphere and the blood through the alveoli Explain Internal Respiration The exchange of gases between the blood and the body cells What do the upper passage ways do? (3) Warm, Filter, Moisten; The passage ways between the nasal cavities and the alveoli conduct gases to and from the lungs What happens during inhalation The contraction of the diaphragm to enlarge the thoracic cavity and draw air into the lungs What happens during exhalation A passive process during which the lungs recoil as the respiratory muscles relax and the thorax decreases in size Where does the interchange of O2 and CO2 take place The alveolar sacs where the interchange of O2 and CO2 takes place through the walls of the grape-like alveoli What does the Alimentary canal/digestive tube consist of? (8) Mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, and anus. What are the accessory organs of digestion? (3) liver, pancreas, and gallbladder What is the process of mastication Where food is mechanically broken down by teeth and tongue How many pairs of salivary glands produce saliva? 3; the saliva lubricates and dilutes food What enzyme does saliva contain and what does it do? Amylase; it starts the digestion of complex CHO What is a bolus A ball of food (formed after amylase begins the digestion of CHO) What muscles force food into the upper portion of the esophagus Constrictive muscles of the pharynx force food into the upper portion of the esophagus and then is swallowed What are the 4 layers of the digestive tract (name from innermost to outer) 1. Mucous membrane 2. Sub mucous layer 3. Muscular layer 4. Serous layer What does the gastric glands of the stomach secrete to break down food? Hydrochloric acid What is Chyme? The stomach muscle churns and mixes the bolus of food, turning the mass into a soupy substance called chyme The stomach also stores and regulates movement of food into the food; small intestine Where does digestion and absorption of food occur? The small intestine; here food is acted on by various enzymes from the small intestine and pancreas and by bile from the liver. Why does the pancreas contribute water to digestion? To dilute chyme and bicarb ions to neutralize the acid from the stomach What are the 3 major regions of the small intestine 1. Duodenum 2. Jejunum 3. ileum Where are nutrients/AA's/Simple sugars/fats absorbed? Nutrients are absorbed through the walls of the small intestine. The AA's and simple sugars are absorbed directly into blood. Most of fats are absorbed into the lymph by the lacteals which are eventually added to the blood stream. After nutrients are absorbed through the walls of the small intestine they enter the be routed to the for hepatic portal vein; liver; decontamination What do villi do They are small finger like projections that increase the surface area of the intestinal wall to What does the large intestine do It reabsorbs water and stores and eliminates undigested food. It also has abundant bacteria called intestinal flora. What are the 5 portions of the large intestine 1. Ascending colon 2. Transverse colon 3. Descending colon 4. Sigmoid colon 5. Rectum (The opening for defecation (expelling of stool) is in the anus Why do the teeth reduce ingested food material to smaller particles To increase surface area for chemical digestion What does the urinary system consist of and their functions? 2 Kidneys: filter blood (regulators of our internal environment) 2 Ureters: tubes that transport urine to the urinary bladder Urinary Bladder: where urine is stored before urination Urethra: urine is expelled thru the urethra to the outside of the body What are the functional units of the kidneys? Functions? Nephrons; They are small coiled tubes that filter waste material out of blood brought to the kidney by the renal artery. Where does the actual filtration process (in kidneys) occur? Through the glomerulus in Bowman's capsule of the nephron. Where does filtration of blood occur In the glomerulus under the force of BP How do components needed by the body reenter the blood? As the glomerular filtrate passes through the nephron, components needed by the body, such as water, glucose, and ions, leave the nephron by diffusion and reenter blood Where is water reabsorbed (kidney)? At the tubules of the nephron What is the final product produced by the millions of nephrons per kidney? Urine What are the 2 functions of the male/female sex organs? Production of gametes (sex cells) and production of hormones- which are under control by the tropic hormones of the pituitary gland How are gametes formed? Meiosis Where does spermatozoa develop (in men)? Within the seminiferous tubules of each testis What produces the testosterone? The interstitial cells between the seminiferous tubules Once produced, the sperm are matured and stored in the epididymis of each testis What is the pathway for ejaculation? What is the medium used to transport sperm and the 3 ex? Vas deferens, ejaculatory duct, urethra. Along the way are glands that produce the transport medium or semen. These include the seminal vesicles, prostate gland, and bulbourethral (Cowpers) gland What does FSH/LH do in men? FSH regulates sperm production and LH (or ICSH) stimulates the interstitial cells to produce testosterone What hormone influences several eggs to ripen within the ovarian follicles in the ovaries? FSH What does estrogen do? Initiates the preparation of the endometrium of the uterus for pregnancy. What happens at day 14 of a women's cycle? LH is released from the pituitary, which stimulates ovulation and the conversion of the follicle to the corpus luteum. What does the corpus luteum do? Secretes estrogen and progesterone; which further stimulates development of the endometrium. If fertilization occurs the corpus luteum remains function/non-functional? Functional; if it does NOT occur it degenerates and menstruation begins What happens to the egg after ovulation? It is swept into the oviduct or fallopian tube. Where does fertilization occur and what happens after It occurs in the oviduct; the fertilized egg or zygote travels to the uterus and implants itself within the enodmetrium. In the uterus the developing embryo is nourished by the placenta, which is formed by maternal and embryonic tissue. During pregnancy, hormones from the placenta maintain the endometrium and prepare the breasts for milk production. Connective Tissue Functions and Properties Gives shapes to organs and holds them in place. Ex. Bone and blood. Has cells scattered throughout an extracellular matrix Epithelial Tissue Functions and Properties Cells tall and thin, no blood vessels in the tissue - Can be found on internal surface of stomach. Muscle types & their function and Properties Cardiac, Skeletal, and Smooth. Cardiac and Skeletal are striated in that they contain sacromeres Smooth muscle has neither. While skeletal muscles are arranged in regular, parallel bundles, cardiac muscle connects at branching, irregular angles Nerve tissue Functions and Properties Functions of the nervous system are sensory input, integration, control of muscles and glands, homeostasis, and mental activity. Bones: What is the epiphysis, diaphysis, Articular cartilage, and Perichondrium. The central shaft is known as the Diaphysis, that widens at each end called an Epiphysis (round part at end of bone). Each epiphysis is covered by a layer of cartilage called articular cartilage to prevent bone from rubbing directly on bone. And Perichondrium is the dense irregular fibrous membrane of connective tissue covering the surface of cartilage except at the endings of joints Compact Bone/Spongy bone Characteristics The dense and hard exterior surface bone is called cortical/compact bone. Cancellous/Spongy bone is found inside of bone & gets its name from the spaces in it making it look sponge like. These spaces contain red bone marrow, which manufactures most of the blood cells.