Human Anatomy and Physiology Quiz

Amphibian hearts have three chambers: two atria and one ventricle.

Reptile hearts are four-chambered, with two atria and a partially divided ventricle.

Bird hearts have four chambers, two atria and two ventricles.

Mammal hearts have four chambers: two atria and two ventricles, with complete separation of oxygenated and deoxygenated blood.

Animals that regulate body temperature through external sources.

Animals that regulate body temperature internally.

Simple excretory structures found in flatworms.

Excretory organs in annelids, arranged metamerically (segmented).

Accessory pumping structures in earthworms, resembling hearts.

The time taken for the electrical signal to travel from the sinoatrial node to the atrioventricular node is approximately 0.1 seconds.

In a monohybrid cross, approximately three-fourths of the offspring will show the dominant phenotype.

Leydig cells are cells in the testes that produce testosterone.

The contraction of striated muscles starts with the release of energy in the presence of calcium ions.

Creatine phosphate is a high-energy phosphate reserve in muscles that quickly regenerates ATP for intense activity.

The production of Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH) by the pituitary gland is regulated by the hypothalamus.

Oxytocin causes labor pains by affecting the myometrium (the muscular tissue of the uterus).

The uterus is the pear-shaped, muscular organ where pregnancy develops in human females.

Bacterial cells maintain their shape through the presence of a cell wall.

Ventilation is the process of bringing oxygen-rich air into contact with the gas exchange surfaces.

Smooth muscles are found in the trachea, bronchi, and bronchioles, but not in the alveoli.

Lymph eventually returns to the circulatory system via the subclavian veins.

The descending aorta splits into two iliac arteries, supplying blood to the thigh muscles

Variation among individuals within a population is the core concept of Darwinism.

Prokaryotes likely first appeared approximately 3.5 billion years ago, according to evolutionary studies.

Competitive inhibitors are similar in structure to substrates and compete for enzyme active sites.

Oxytocin is a hormone that causes the milk ducts in mammary glands to dilate.

In a typical nerve, the duration of an action potential is approximately 1 millisecond.

Neurotransmitters are chemical messengers that transmit signals across synapses.

Pacinian corpuscles are pressure receptors in the human body that detect deep pressure stimuli.

A period of time after a nerve impulse where the nerve cell cannot respond to another stimulus.

The prominent thyroid cartilage in the neck.

Part of the brain stem controlling vital functions like heart rate and breathing.

Brain region controlling the autonomic nervous system and pituitary gland.

Causes personality disorders and inappropriate social behavior.

Major nerve supplying many organs in the chest and abdomen, plus head and neck.

Immune cells that clean up synapses.

Determines the effect of a neurotransmitter (e.g., constrict or dilate blood vessels).

One neurotransmitter having both inhibitory and excitatory effects, depending on the receptor.

Light-sensitive cells active in dim light.

Generally larger in females compared to males.

Cold temperatures are likely to stimulate TSH release.

Hypocalcemia (low calcium) is a potential risk after thyroid surgery.

Pancreas has more exocrine (90%) than endocrine (10%) tissue.

Hypersecretion of growth hormone in adulthood, causing changes in bones and tissues.

GnRH (Gonadotropin-Releasing Hormone) is secreted first.

Sex cells (sperm and egg).

Sperm is stored in the epididymis until ejaculation.

Cells in the testes that produce testosterone.

The seminal vesicles contribute most of the volume to semen.

A surge of LH triggers ovulation.

Drop in estrogen and progesterone levels triggers menstruation.

William Bateson coined the term 'genetics' in 1906.

Mating between individuals with different alleles at one gene.

True-breeding organism for a particular trait.

Heterozygous phenotype is intermediate between homozygous phenotypes.

Small bones embedded in tendons or muscles, often near joints.

The electrical potential difference across a cell membrane when it's not stimulated(-70mV).

30 times greater inside than outside the cell.

Nearly 10 times greater outside than inside the cell.

Membrane protein maintaining ion gradients by pumping 3NA+ out and 2K+ in.

Chemical messengers transmitting signals across synapses.

Part of the autonomic nervous system, prepares for stress (fight or flight).

Part of the autonomic nervous system, promotes relaxation and maintenance (rest and digest).

Cranial nerve 10, primarily parasympathetic.

Division of the peripheral nervous system controlling voluntary movements and sensory input.

Cone-shaped papillae, covering the entire tongue, lacking taste buds.

Mushroom-shaped papillae, located at tongue tip and sides, with taste buds.

Folded papillae along sides of tongue, containing taste buds.

Flat, mound shaped papillae at the back of the tongue, containing taste buds.

Over 1000 types, each sensitive to a different odor.

Decreases with hair removal.

The middle loop in all transfer RNA molecules is composed of 7 base pairs.

One turn of the DNA double helix consists of 10 base pairs.

Ribozymes are enzymes composed of RNA.

The active site of an enzyme typically consists of 3-12 amino acids.

Bacteriophage capsids have 12 vertices and 20 faces.

Polio virus has 32 capsomers.

Herpes viruses possess 162 capsomers.

Adenoviruses, which cause common colds, have 252 capsomers.

Ribosomal RNA (rRNA) is commonly used as a molecular clock.

Mycoplasma bacteria have a diameter of 0.1-0.2 μm.

Escherichia coli have a diameter of 1.8 μm.

Escherichia coli have a length of 7 μm.

Bacterial flagella have a diameter of 20 nm.

Bacterial flagellum have a length of 20 μm.

Milk is pasteurized by heating at 71°C for 15 seconds and 62°C for 32 minutes.

The gastrointestinal tract (GIT) is approximately 9 m (30 ft) long.

Saliva has a pH between 6 and 7.

The oesophagus is 25 cm long.

Villi have a length of 0.5-1.5 mm.

The vermiform appendix is 9 cm long.

The gall bladder is 8 cm long.

The gall bladder is 4 cm wide.

Capillaries are 1 mm long.

The aorta has a diameter of 23 mm.

Arterioles have a diameter of 0.2 mm.

Venules have a diameter of 40-50 μm.

Veins have a diameter of 2 mm.

The cross-sectional area of the aorta is about 2.5 cm^2^.

Blood speed in the aorta is approximately 30 cm/s.

Blood speed in capillaries is approximately 0.26 cm/s.

A phospholipid is formed from phosphatidic acid combined with a nitrogenous base, amino alcohol, or amino acid (e.g., choline).

Acylglycerols are the most common lipids in living things.

Each intermediate filament is made of three vimentin chains.

Amyloplasts store starch.

Elaioplasts store lipids.

Proteinoplasts store proteins.

3 pairs of cranial nerves are sensory, 5 are motor, and 4 are mixed.

At the laryngopharynx, the respiratory and digestive systems diverge.

Alveoli contain collagen and elastic fibers to enable expansion and recoil.

Isoniazid and rifampicin are common TB drugs.

Molluscs, annelids, and arthropods fall into the protostome category.

Echinoderms and chordates are deuterostomes.

Aschelminths (nematodes or roundworms) are pseudocoelomates.

Platyhelminths (flatworms) are acoelomates.

The posterior part of the brain, consisting of the medulla oblongata, pons, and cerebellum.

Part of the hindbrain; connects to the spinal cord and controls vital functions like breathing and heart rate.

Cerebrum, limbic system, and thalamus are the main parts of the forebrain.

Hypothalamus, amygdala, and hippocampus make up the limbic system.

The largest part of the forebrain, responsible for higher-level functions and thinking.

The cerebrum has left and right hemispheres connected by the corpus callosum, sending signals between them.

A band of axons connecting the left and right hemispheres of the cerebrum.

The cerebrum has four main lobes: frontal, parietal, temporal, and occipital.

The cerebrum contains sensory, association, and motor areas.

A relay center for sensory information (except smell) to the limbic system, located below the cerebrum.

Controls homeostasis, emotions, and hormone release; part of the limbic system.

Almond-shaped structures in the limbic system related to emotions (fear, pleasure).

Brain region associated with learning and forming long-term memories.

A reduced part of the brain in humans; acts as a relay center for visual and auditory information.

A part of the brainstem that connects the cerebrum, medulla, and cerebellum and controls breathing.

A part of the hindbrain responsible for coordination, movement, and balance.

Stiffening of muscles after death, lasting approximately 34 hours.

16 nm in diameter

7-8 nm in diameter

1-3 ms^-1^ in humans

Up to 120 meters per second