key terms unit 2

Question 1

endocrine gland

Answer 1

Endocrine glands are glands of the Endocrine system that secrete hormones directly into the bloodstream to a target gland or organ.

Examples: adrenal gland, pancreas, thyroid gland, hypothalamus, pituitary gland

Question 2

exocrine gland

Answer 2

Exocrine glands are glands that secrete substances onto the surface.

Examples: sweat, salivary, mammary

Question 3

peptide hormone

Answer 3

Peptide hormones are hormones that bind to the receptors on the surface of the cell because they are lipophobic(fat-hating)

Examples: Insulin, Glucagon, Oxytocin

Question 4

steroid hormone

Answer 4

Steroid hormones are hormones that bind to the receptor inside the cell(nucleus or cytoplasm) because they are lipophilic(fat-loving).

Examples: Estrogen and Testosterone

Question 5

cornea

Answer 5

A tough, clear covering over the iris and the pupil that helps protect the eye. Light bends as it passes through the cornea. This is the first step in making an image on the retina. The cornea begins bending light to make an image; the lens finishes the job.

Question 6

pupil

Answer 6

The pupil is the dark circle in the center of your iris. It’s a hole that lets light into the inner eye. Your pupil is round, a cows pupil is oval.

Question 7

aqueous humor

Answer 7

A clear fluid that helps the cornea keep its rounded shape.

Question 8

iris

Answer 8

A muscle that controls how much light enters the eye. It is suspended between the cornea and the lens. Human iris’ comes in many colors.

Question 9

lens

Answer 9

A clear, flexible structure that makes an image on the eye’s retina. The lens is flexible so that it can change shape, focusing on objects that are far away.

Question 10

retina

Answer 10

The layer of light-sensitive cells at the back of the eye. The retina detects images focused by the cornea and the lens. The retina is connected to the brain by the optic nerve.

Question 11

vitreous humor

Answer 11

The thick, clear jelly that helps give the eyeball its shape.

Question 12

sclera

Answer 12

The thick, tough, white outer covering of the eyeball.

Question 13

blind spot

Answer 13

The place where the optic nerve leaves the retina. Each eye has a blind spot where there are no light-sensitive cells.

Question 14

optic nerve

Answer 14

The bundle of nerve fibers that carry information from the retina to the brain.

Question 15

tapetum

Answer 15

The colorful, shiny material located behind the retina. Found in animals with good night vision, the tapetum reflects light back through the retina.

Question 16

accommodation

Answer 16

Accommodation is the combination of reflex actions by which the lens of the eye changes to keep the distance between the center of the lens and its focal point, constant. Ciliary muscles in the eye assist adjustment of the lens.

Question 17

afterimages

Answer 17

Afterimages are optical illusions that occur when looking away after staring at intently at a fixed image or color. The constant light stimulating the retina causes the cones in that area to become fatigued, and after looking away from the image, the less-stimulated cones, which are not fatigued still function.

Question 18

astigmatism

Answer 18

Astigmatism is a condition in which the cornea of the lens is irregularly shaped. This shape change causes incoming light rays to converge improperly. The light rays do not focus at the specific point on the retina and can cause blurry or distorted images.

Question 19

color vision

Answer 19

Color vision is possible because of the retina, which contains two types of photoreceptors - rods and cones. Impulses from the rods and cones pass through the nerve cells to the optic nerve.

Question 20

cones

Answer 20

Cones are a type of photoreceptor that function in bright light and provide sharp, colorful images. There are three cones(blue, red, and green) which combine to see other colors as well. If one cone malfunctions, color blindness can occur.

Question 21

depth perception

Answer 21

Depth perception is the ability to judge the relative distances between objects in three dimensions.

Question 22

optical illusions

Answer 22

Optical Illusions are visual tricks that take place in the brain rather than the eye. The visual cortex of the brain decipher images sent from the eye, but surrounding objects cause the mind to interpret the image differently.

Question 23

peripheral vision

Answer 23

Peripheral Vision is the ability to see things that fall outside of our direct line of vision. This vision is better for detecting movement than for processing sharp images and is most strong in the dark.

Question 24

rods

Answer 24

Rods are one of our photoreceptors and function in dim light to see shades of gray.

Question 25

growth hormone

Answer 25

The growth hormone is secreted by the pituitary gland, targets the liver and other tissues causing growth of bone, liver, or fat.

Question 26

oxytocin

Answer 26

Oxytocin is secreted by the pituitary gland, targets the breasts, uterus, and mammary gland causing contractions and helping male reproduction.

Question 27

adrenaline

Answer 27

Adrenaline is secreted by the adrenal glands, targets the heart causing a faster heartbeat, an increase in blood flow to the brain and muscles while helping the body to react quickly.

Question 28

MSH

Answer 28

MSH is secreted by the pituitary gland and causes skin darkening.

Question 29

FSH

Answer 29

FSH is secreted b the pituitary gland, targets the testes/ovaries causing pubertal maturation, regulates development, growth and reproductive processes.

Question 30

LH

Answer 30

LH is secreted by the pituitary gland, targets the gonads causing control of the testes/ovaries.

Question 31

ACTH

Answer 31

ACTH is secreted by the pituitary gland, targets the adrenal cortex causing regulation of the steroid hormone, cortisol.

Question 32

TSH

Answer 32

TSH is secreted by the pituitary gland, targets the thyroid gland causing stimulation of the metabolism of tissues.

Question 33

myopia

Answer 33

• nearsightedness
• eyeball is too long
• image lands in front of the retina
• divergent lens(concave)

Question 34

hyperopia

Answer 34

• farsightedness
• eyeball is too short
• image lands beyond the retina
• convergent lens(convex)