Chapter 4 - Homeostasis

Question 0

Positive feedback

Answer 0

Process by which a small effect is amplified, less common in the body

• platelets clamp to form blood clots that signal more platelets are activated
• when breast-feeding the more the baby suckles the more milk is produced
• during follicular phase estrogen causes thickening of the uterine lining

Question 1

Negative feedback mechanism

Answer 1

The process by which a mechanism is activated to restore conditions to their original state

Question 2

Osmoregulation

Answer 2

The process of actively regulating the osmotic pressure of bodily fluids and cells

Question 3

Nephron

Answer 3

The tiny functional unit of the kidney that filters waste from the blood

Question 4

Thermoregulation endotherm’s

Answer 4

• maintain a constant body temperature regardless of their surroundings
• decrease in environmental temperature stimulates an increase in cellular respiration
• normal body temperature in humans is 37°C
• some have special behavioral and psychological adaptations to help thermoregulation

Question 5

Sympathetic nervous system

Answer 5

Prepares the body for stress (ex increases blood flow). Runs through spinal cord

Question 6

Parasympathetic nervous system

Answer 6

Restore normal balance (ex. Decreased blood flow). Contains cranial nerve, which links the brain direct path to the body

Question 7

How blood sugar levels are regulated

Answer 7

Pancreas

• made of two cells:
• one type produces digestive enzymes
• the other produces hormones: located in the islet of langerhans
• beta and alpha cells are responsible for the production of two hormones, insulin and glucagon

Insulin

• produced in the beta cells, released when the blood sugar levels increase
• causes cells of muscles, liver and other organs to become permeable to glucose
• in the liver glucose is converted to glycogen

Glucagon

• produced in the Alpha cells, causes an increase in the blood sugar level which means they’re released when blood sugar levels are low
• converts glycogen to glucose

Question 8

Sensory neuron (afferent neurons)

Answer 8

Carry impulses from sensory receptors to the central nervous system

Question 9

Sensory receptors

Answer 9

Examples are photoreceptors in eyes (light), thermoreceptors in the skin, hypothalamus (heat/cold)

Question 10

Motor neurons (efferent neurons)

Answer 10

Carry impulses from the central nervous system to effectors. Things that produce a response such as muscles organs and glands

Question 11

Homeostasis

Answer 11

Process by which a constant internal environment is maintained despite changes in the external environment

Question 12

Steroid hormones

Answer 12

• made from cholesterol
• fat soluble
• passes through lipid bilayer
• combined with hydrophilic carrier proteins to form water soluble complexes
• ex. sex hormones

Question 13

Protein hormones

Answer 13

• made of amino acid chains
• water soluble
• diffuse well in bloodstream
• combine with receptors on cell membrane
• ex. insulin and growth hormone

Question 14

Mechanoreceptors

Answer 14

Detects mechanical energy, so changes in pressure, body position or acceleration. An example is auditory receptors in the ears

Question 15

Photoreceptors

Answer 15

Detector light energy. Located mainly in the retina

Question 16

Chemoreceptors

Answer 16

To text specific molecules are chemical conditions, such as the acidity. An example is taste buds on the tongue

Question 17

Thermoreceptors

Answer 17

Detect the flow of thermal energy. Located in the skin

Question 18

Nociceptors

Answer 18

Pain receptors that detect tissue damage. Recognize pain. Located in skin and some internal organs

Question 19

Myelinated nerve cells

Answer 19

Fatty material that coats protects and insulates nerve cells enabling them to quickly conduct impulses between the brain and different parts of the body

Question 20

Non-myelinated nerve cells

Answer 20

A nerve that is bear or without the myelin sheath around the axon. It’s slower and conducting impulses and are found in the peripheral nervous system and the gray matter of the nervous system