Science practice test

A person is suddenly frightened. Which of the following reactions occurs next?

A. Liver cells absorb glucose from the blood stream

B. Blood vessels supplying skeletal muscles constrict

C. Blood vessels supplying the intestines dilate

D. Liver cells release glucose into the blood stream

D

Epinephrine causes liver cells to break down glycogen, which causes an increase in sugar in the blood stream

_____ causes liver cells to break down glycogen, causes an increase in sugar in the blood stream

Epinephrine

_____ causes blood vessels supplying skeletal muscles to dilate?

Epinephrine

_____ causes intestines to constrict, restricting blood flow to the organs of the digestive system?

Epinephrine

Which of the following is an example of positive feedback?

A. Oxytocin causes an increase in uterine muscle contractions, ultimately causing the posterior pituitary to release more oxytocin

B. An increase in blood glucose level causes the release of insulin, which results in the lowering of glucose levels in the blood and halting the release of insulin

C. A drop in body temperature causes the hypothalamus to activate warming mechanism, which results in the increase of body temperature

D. An increase in blood osmolarity causes the release of ADH, which causes urine to become more concentrated and osmolarity to decrease

A

when a response reinforces a stimulus, causing an even greater response, positive feedback in occurring

Is this a negative or positive feedback?

An increase in blood glucose level causes the release of insulin, which results in the lowering of glucose levels in the blood and halting the release of insulin

Negative

the response of lower glucose levels reduce the initial stimulus and stop the pancreas from releasing insulin

Is this a negative of positive feedback?

A drop in body temperature causes the hypothalamus to activate warming mechanism, which results in the increase of body temperature

Negative

the response increasing body temperature reduces the initial stimulus and stop the hypothalamus from activating warming mechanisms

Is this a negative of positive feedback?

An increase in blood osmolarity causes the release of ADH, which causes urine to become more concentrated and osmolarity to decrease

Negative

an osmolarity increase causes a response that decreases osmolarity and reduces the release of ADH

Demyelinization results in which of the following?

A. Inhibited detection of a stimulus at the dendrites of a nerve cell

B. Disrupted propagation of an action potential along the axon of a nerve cell

C. Inhibited uptake of neurotransmitters at the synapse of a nerve cell

D. Disrupted ability of the Na+/K+ pumps to depolarize a cell

B

Myelin sheath, which I a lipid-based structure, insulates the axon, allowing rapid electrical conduction of the action potential down the axon. Deterioration of the myelin sheath disrupts this process

The nephridium in worms has a function most similar to which the following organs in humans?

A. Liver

B. Spleen

C. Lymph nodes

D. Kidney

D

Nephridia is segmented worms operate similarly to the nephron of the kidneys. Nephrons in the kidneys contain a collecting tubule that aids in urine production

the organ that produces bile, regulates glycogen storage

Liver

the organ that remove old, fragmented red blood cells and pathogens from blood

Spleen

______ filter out pathogens from interstitial fluids?

lymph nodes

Which of the following cell types is responsible for the production of soluble antibodies?

A. Cytotoxic T-cell

B. Macrophage cell

C. Helper T-cell

D. B-cell

D

the production of antibodies by B-cells is part of the humoral response to antigens

what kind of cell destroy pathogens and infected cells?

Cytotoxic T-cells

What kind of white blood cell ingest and digest both non-self cells and dead cells?

Macrophages

Which of the following organ system is responsible for transporting nutrients, wastes, and other substances throughout the human body?

A. Respiratory

B. Immune

C. Nervous

D. Circulatory

D

the heart pumping blood through the arteries, capillaries, and veins provide the means of transporting substances throughout the body

_____ system is in charge of exchanging gases with the outdid environment, bringing oxygen in and letting carbon dioxide out?

Respiratory

_____ system is in charge of protecting the body from pathogens using a combination of white blood cells and antibodies?

Immune

_____ system is includes the brain, spinal cord, and peripheral nerves, control the actions of other body systems?

Nervous

Which of the following is characteristic of the human organism?

A. Autotrophic with a genome stored in DNA

B. Heterotrophic with a genome stored in DNA

C. Autotrophic with a genome stored in RNA

D. Heterotrophic with a genome stored in RNA

B

Human consume rather than manufacture nutrient molecules, human gene encoded in DNA

Which of the following is the function of the lymph nodes in mammals?

A. Pump oxygen into tissue spaces

B. Store extra glucose for emergencies

C. Synthesize hemoglobin for erythrocytes

D. Filter debris from intracellular spaces

D

filter debris, lymphocytes, and pathogens from intracellular fluid

Glucose is stored as glycogen in what organ muscle of mammals?

liver

The bands in muscle sarcomere are formed by actin and which of the following other proteins?

A. Myosin

B. Dynein

C. Karatin

D. Laminin

A

contains “heads” that contact actin and pull the actin fibers together in an ATP-dependent mechanism that causes muscles to contract

_____ is and ATP-dependent molecule that “walk” along microtubules, causing them to move, but it is not part of the sarcomere?

Dynein

_____ is a fibrous protein of hair and nails and not part of the sarcomere?

Keratin

____ is a protein of the nuclear envelope and is not part of the sarcomere?

Laminin

Which of the following structures within a human cell is responsible for recycling the materials no longer functional or needed within the cell?

A. Ribosome

B. Lysosome

C. Mitochondrion

D. Nucleolus

B

specialized vacuoles containing digestive enzyme

function in cellular respiration, facilitating the production of ATP

Mitochondria

functions in the assembly of ribosome

nucleolus

Which of the following is the correct structure and function of the cell membrane?

A. A double glycoproteins structure with embedded lipid bodies provides shape and rigidity to the cytoplasm

B. A double layer of phosphate proteins with lipid channels allows molecules to pass from the Indies to the outside of cells

C. Nonpolar phosphate heads and polar lipid tails form a bilayer to control the transport of proteins

D. A phospholipid bilayer with embedded proteins regulates molecules entering and leaving cytoplasm

D

the cell membrane consists of a phospholipid bilayer with polar phosphate heads, nonpolar lipid tails, and embedded proteins, which permit the movement of molecules across the membrane

In which of the following areas does protein breakdown begin in the human body?

A. Mouth

B. Stomach

C. Small intestine

D. Large intestine

B

is the first place in the digestive system in which proteinases are produced

Carbohydrates digestion start in where of the human body?

mouth

Which of the following chemical compounds prevents the lungs from collapsing?

A. Mucus

B. Surfactan

C. Enzymes

D. Buffers

B

are lipopolysaccharides that have a hydrophobic and hydrophilic layer. They keep the lungs inflated

Lipopolysaccharides that have a hydrophilic layer that keep the lungs inflated?

surfactants

Which of the these structures diverts food into the esophagus, and prevents it from entering the lungs?

A. Uvula

B. Soft palate

C. Tonsils

D. Epiglottis

D

shuts off the tracheal opening, diverting food into the esophagus

_____ is found in the back of the throat and prevents food entry into the nasal passage?

Uvula

_____ is found in the back of the buccal cavity. It helps in swallowing and prevents food entry into the nasal passages?

soft palate

_____ are made of lymphatic tissue the does not typically interfere with food movement?

tonsils

Which of these terms related to the respiratory system refers to the “voice box” for sound production?

A. Pharynx

B. Trachea

C. Larynx

D. Uvula

C

a cartilaginous structure containing the vocal cords, which is used to generated sound

_____ is the muscular region at the intersection of the respiratory and digestive systems?

pharynx

_____ is the large tube containing cartilaginous rings through which air passes into and out of the lungs?

trachea

_____ is a fleshly extension of the back of the soft palate, hanging above the throat?

Uvula

Unlike skeletal muscle, cardiac muscle is highly resistant to lactate-mediated fatigue because cardiac muscle

A. uses aerobic respiration in mitochondria for energy

B. operates with electrical energy supplied by the sinoartrial (SA) node

C primarily metabolize glucose using the fermentation pathway

D. does not need oxygen for the production of energy

A

almost exclusively used by the heart

_____ also known as the pacemaker, produces electrical impulses for the heart contraction. It does not provide energy to the heart

Sinoatrial (SA) node

the lactose-producing fermentation pathway operates during ____ deprivation in the skeletal muscle.

Oxygen

Which of the following arteries directly supplies oxygenated blood to the reproductive system?

A. Common carotid artery

B. Gonadal artery

C. Femoral artery

D. Subclavian artery

B

the primary artery that supplies oxygenated blood to the gonads and male reproductive system. Its Calle testicular artery in males and ovarian artery in females

_____ artery supplies oxygenated blood to the head?

common carotid

_____ artery supplies oxygenated blood to the lower limbs?

femeral

_____ artery supplies oxygenated blood to the upper limbs?

subclavian

Which of the following options represents the chromosomal composition of a normal human zygote?

A. 23 chromosomes

B. 46 chromosomes

C. 69 chromosomes

D. 92 chromosomes

B

the fusion of a sperm with 23 chromosomes and an egg with 23 chromosomes would result in a zygote with 46 chromosomes

Which of the following produces progesterone to prepare the uterus for pregnancy?

A. Endometrium

B. Cervix

C. Corpus luteum

D. Fallopian tubes

C

refers to the remnant of the Grain folic. It secretes progesterone to prepare the uterus for the pregnancy

____ a highly vascularized tissue of the uterine lining

endometrium

_____ is the external opening of the uterus

cervix

______ carries the egg from the ovary to the uterus

fallopian tube

Which of the following cell type provides a waterproofing function for the outer layers of skin?

A. Melanocytes

B. Keratinocytes

C. Merkel cells

D. Langerhans cells

B

produce in the epidermis and migrate upwards, tight junctions between cells prevent water entry

_______ pigment cells found in the lowest layer of the epidermis of the skin, the basal layer, produce melanin

Melanocytes

______ cells that work as mechanoreceptors and sense touch and pressure

Merkel cells

_____ are dendritic cells of the immune system and are found in the lower layers of the epidermis. They immunologically process material that enters through the skin

Langerhans

Stores of subcutaneous fat can be found in which of the following layers of the skin in the human body?

A. Epidermis

B. Dermis

C. Hypodermis

D. Dermal papillae

C

_____ contains living and dead keratinocytes, melanocytes, as well as dendritic and tactile cells

epidermis

_____ a layer of skin that contains blood capillaries, hair shafts, nail roots, and sweat glands

dermis

_____ are wavy projections of the dermis into the epidermis that lock the two layers together

dermal papillae

Which of the following glands primarily supplies hair shafts and skin with oily secretions?

A. Eccrine gland

B. Apocrine gland

C. Sebaceous gland

D. Ceruminous gland

C

_____ gland are distributed across the surface of the skin and produce a dilute, salty sweat

Eccrine, or merocrine

____ usually found in the groin and armpits and produce sweat and scent

Apocrine

_____ produce a waxy secretion in the ear canals

cerumionous

Which of the following glands is the primary producer of insulin?

A. Thyroid

B. Adrenal

C. Pituitary

D. Pancreas

D

_____ produces thyroid and stress hormone

adrenal

_____ secretes hormones that control other glands

pituitary

Type I diabetes is a disease associated with which of the following hormones?

A. Estrogen

B. Insulin

C. Testosterone

D. Thyroxine

B

Which of the following connects the kidneys to the bladder?

A. Capillaries

B. Ureters

C. Urethras

D. Arteries

B

_____ connect veins to arteries

capillaries

_____ connect the bladder to the outside of the body

urethras

_____ carry blood away from the heart

arteries

Which of the following organs is the site of blood filtration?

A. Kidney

B. Heart

C. Lung

D. Brain

A

Kidneys remove which of the following from the blood?

A. Platelets

B. Salts

C. Oxygen

D. Fat

B

_____ removed by the spleen and liver

platelets

In which part of the body to T-cells mature?

A. Bone marrow

B. Thymus

C. Adrenal glands

D. Thyroid

B

_____ are produced in the bone marrow, but they are not matured.

T-cells

_____ produce several hormones, but they do not produce parts of the immune system

Adrenal glands

Which of the following is classified as a flat bone?

A. Tarsal

B. Vertebra

C. Rib

D. Humerus

C

Which of the following connects two bones together?

A. Ligament

B. Tendon

C. Marrow

D. Muscle

A

connect bones to bones

Ligaments

connect muscle to bone

Tendons

Which of the following are sesamoid bones?

A. Phalanges

B. Patellae

C. Scapulae

D. Metatarsals

B

response to strain

The shape of villi and microvilli facilities which of the following?

A. Pushing food along the intestine via ciliary motion of villi

B. Creating barriers to food movement to increase digestion time

C. Decreasing surface area for absorption

D. Increasing surface area for absorption

D

the folds increase the surface area, allowing more nutrients to be absorbed and delivered to the blood stream

Ca+H2SO4 which of the following statements correctly describes the product of the reaction above?

A. Calcium sulfate

B. Hydrogen sulfide

C. Calcium sulfide

D. Hydrogen sulfate

A

calcium and sulfuric react to produce calcium sulfate and hydrogen gas

Which of the following classes of biomolecules can influence the rate of specific chemical reactions within the living cell?

A. Nucleic acids

B. Proteins

C. Lipids

D. Carbohydrates

B

some fold into shape that allow them to function as biochemical catalysts or enzymes within a cell

these contain genetic information for the synthesis of proteins

Nucleic acid

these molecules, which repel water, function in cellular membranes and in the storage of excess energy

lipids

these “sugar and starch” molecules function in energy input and storage, as well as in some functional capacities

carbohydrates

Which of the following terms describes a sample composed of particles condensed into a small space and having vibrational, but not translational, motion?

A. Solid

B. Liquid

C. Gas

D. Plasma

A

_____ have little space between particles, and the particles vibrate within a fixed lattice structure

solids

_____ particles move about in a fluid manner due to translational motion

liquid

______ particles are widely separated by empty space and move about randomly due to translational motion

gas

_____ in a plasma state move so rapidly that their electrons separate from the rest of the atom

atoms

An atom has 3 protons, 4 neutrons, and 3 electrons. Which of the following is the atom’s mass number?

A. 3

B. 6

C. 7

D. 10

C

\#protons + #neutrons =

mass of an atom

Which of the following substances will dissolve in water?

A. CH4

B. CCl4

C. CH3OH

D. C8H18

C

polar molecule, oxygen is highly electronegative and draws electrons toward itself