practice questions

What is the name for a group of bundled skeletal muscle cells surrounded by connective tissue?
A) Myofilament
B) Sarcomere
C) Fascicle
D) Endosteum

c

Which ion must bind to troponin to initiate skeletal muscle contraction?

A) Potassium

B) Sodium

C) Chloride

D) Calcium

d

Which muscle type is both involuntary and lacks striations?

A) Skeletal

B) Cardiac

C) Smooth

D) Voluntary

c

1. During muscle contraction, the physical connection formed between thick and thin filaments is called a:
   A) Fiber link
   B) Tension clamp
   C) Cross-bridge
   D) Z-disc

c

Which molecule is released into the synaptic cleft at the neuromuscular junction?

A) GABA

B) Serotonin

C) Acetylcholine

D) Dopamine

c

Which of these bones is considered part of the central axis of the human skeleton?

A) Clavicle

B) Femur

C) Vertebra

D) Scapula

c

The hollow chamber within the shaft of a long bone that houses fat is called the:

A) Epiphysis

B) Central canal

C) Medullary cavity

D) Osteon

c

The mineral salt primarily responsible for bone rigidity is:

A) Collagen

B) Calcium carbonate

C) Hydroxyapatite

D) Keratin

c

Which bone cell type functions to break down bone tissue?
A) Osteocytes
B) Osteoblasts
C) Osteons
D) Osteoclasts

d

Which joint allows for movement in multiple directions including rotation?
A) Hinge
B) Ball-and-socket
C) Plane
D) Saddle

b

Which glial cell lines the ventricles of the brain and helps circulate cerebrospinal fluid?

A) Oligodendrocyte

B) Astrocyte

C) Ependymal cell

D) Schwann cell

c

Which neuron part receives signals from neighboring neurons?
A) Axon
B) Soma
C) Myelin sheath
D) Dendrite

d

What division of the nervous system regulates involuntary actions like heart rate?

A) Somatic

B) Autonomic

C) Central

D) Motor

b

Norepinephrine is broken down in the synapse by which enzyme?
A) Acetylcholinesterase
B) Monoamine oxidase
C) Peptidase
D) Nucleotidase

b

Which brain region plays a key role in maintaining internal homeostasis such as body temperature and thirst?
A) Thalamus
B) Cerebellum
C) Hypothalamus
D) Pons

c

Which gland is responsible for producing the oil that lubricates skin and hair?

A) Eccrine

B) Apocrine

C) Sebaceous

D) Sudoriferous

c

What pigment helps shield the DNA in skin cells from ultraviolet radiation?

A) Hemoglobin

B) Melanin

C) Elastin

D) Keratin

b

The most common and least dangerous form of skin cancer typically arises in which epidermal layer?

A) Stratum corneum

B) Stratum basale

C) Stratum granulosum

D) Dermis

b

Which retinal structure allows for the clearest, most detailed vision?

A) Optic disc

B) Retina margin

C) Fovea centralis

D) Iris

c

In which part of the ear are the organs for hearing and balance located?

A) External ear

B) Tympanic cavity

C) Inner ear

D) Auditory canal

c

Receptors that sense changes in body movement and spatial orientation are called:

A) Thermoreceptors

B) Proprioceptors

C) Nociceptors

D) Baroreceptors

b

What transport process moves substances against a concentration gradient using ATP?

A) Diffusion

B) Facilitated diffusion

C) Active transport

D) Osmosis

c

Which structure in the cell converts nutrients into usable energy?

A) Ribosome

B) Nucleus

C) Golgi apparatus

D) Mitochondrion

d

A positively charged ion formed by the loss of an electron is called a:

A) Anion

B) Isotope

C) Cation

D) Neutron

c

When two atoms share electrons, the bond formed is called:

A) Ionic

B) Hydrogen

C) Covalent

D) Metallic

c

Which organelle acts as the post office of the cell, packaging proteins for delivery?

A) Ribosome

B) Mitochondrion

C) Golgi apparatus

D) Centriole

c

What happens to a red blood cell placed in a solution with a higher solute concentration than inside the cell?

A) It swells

B) It bursts

C) It shrinks

D) Nothing changes

c

Which gyrus of the cerebral cortex is responsible for processing sensory input from the body?

A) Precentral gyrus

B) Central sulcus

C) Postcentral gyrus

D) Occipital lobe

c

Which neurotransmitter is released by all preganglionic neurons of the autonomic nervous system?

A) Epinephrine

B) Dopamine

C) Acetylcholine

D) Serotonin

c

When several neurons transmit signals to a single postsynaptic neuron simultaneously, this is called:

A) Divergence

B) Facilitation

C) Temporal summation

D) Spatial summation

d