The Human Body: An Orientation Chapter Maintaining life

Bellwork Write these vocabulary words on your bell work sheet 2 9. cephal 10. cyto/cyte 11. Anatomy 12. Physiology 13. Metabolism 14. Homeostasis 15. Tissue 1.a-/an 2.ad 3.ana 4.anti 5.arthr 6.auto 7.bi 8.cata-

Now with a partner define these. You can use your books, or your phone Quiz: This Friday

1.a-/an 2.ad 3.ana 4.anti 5.arthr 6.auto 7.bi 8.cata- 9.cephal- 10.cyto/cyte 11. Anatomy 12. Physiology 13. Metabolism 14. Homeostasis 15. Tissue #1-10 Include a word using the prefix or suffix as an example

Life Processes of Humans ▪ Vocabulary Metabolism: Chemical process to breakdown large, complex molecules into smaller ones Energy is released and new materials can be made Responsiveness: Ability to sense changes and react 5

Life Processes of Humans ▪ Vocabulary Movement: Motion of organelles, cells, organs or the whole body Growth: An increase in body size Increase in size of cells, number of cells or amount of material surrounding cells 6

Life Processes of Humans ▪ Vocabulary Differentiation:Unspecialized cells(stem cells) become specialized Reproduction: Formation of new cells for growth, repair or replacement. Production of a new individual Examples: Stem cells become white blood cells Stem cells become kidney cells Etc. 7

Life Processes of Humans ▪ Review Pay attention, you might see these questions again(hint, hint) 8

Life Processes of Humans A: MovementB: Metabolism C: Differentiation D: Responsiveness E: Growth F: Reproduction 1.________ Chemical processes which involve the breakdown of large complex molecules into smaller ones with a release of energy 9

Life Processes of Humans A: MovementB: Metabolism C: Differentiation D: Responsiveness E: Growth F: Reproduction 2.________ Changes that cells undergo during development from unspecialized to specialized; like bone or muscle 10

Life Processes of Humans A: MovementB: Metabolism C: Differentiation D: Responsiveness E: Growth F: Reproduction 3.________ Formation of new cells for growth, repair, or replacement, or for production of a new individual 11

Life Processes of Humans A: MovementB: Metabolism C: Differentiation D: Responsiveness E: Growth F: Reproduction 4.________ Ability to detect and respond to changes in the environment 12

Life Processes of Humans A: MovementB: Metabolism C: Differentiation D: Responsiveness E: Growth F: Reproduction 5.________ Food passes through the body, change location, blood cells travel around the body 13

Life Processes of Humans ▪ Pick a life process and explain why it’s important to sustaining life 14

Objectives: Part 2 1.Define homeostasis and explain its importance 2.Describe the components of a feedback system 3.Compare the operation of negative and positive feedback systems 15

Homeostasis Homeostasis: Maintenance of a stable environment A.K.A: a balance Body’s internal environment stays the same even when the external environment changes Under control of the nervous system and the endocrine system 16

Homeostasis Nervous System: detects changes in the system and sends signals to organs Endocrine System: produces hormones to correct changes and restore homeostasis 17 Quick Response Slow Response

Homeostasis ▪ Feedback Loops: cycle of events in which the body is continuously monitored. Examples: body temperature, blood pressure, blood glucose Can be positive or negative 18

Homeostasis ▪ Feedback Loops Continued 3 Components to a Feedback Loop 1.Receptor: A type of sensor that responds to changes in the environment Sends nerve impulses or chemical signals to the control center Example: nerve endings in your fingers 19

Homeostasis ▪ Feedback Loops Continued 3 Components to a Feedback Loop 2.Control Center: What is known as the human control center? Evaluates and analyzes the information it receives from the receptor and then determines the response The Brain 20

Homeostasis ▪ Feedback Loops Continued 3 Components to a Feedback Loop 3.Effector: A body structure(muscle or gland) that acts out the control center’s response to the stimulus Feedback Loop 21

Homeostasis 22

Homeostasis ▪ Feedback Loops Continued Negative Feedback Loop: Negative Feedback= For example when you get to hot and start sweating Includes most homeostatic control mechanisms: 99% Works like a household thermostat Shuts off the original stimulus, or reduces its intensity 23 GOING BACK TO NORMAL

Thermostat is set to 72 o, what happens when the temperature drops 1. Thermostat (Receptor) detects drop in temperature ( ) 2. Furnace ( ) turns on to release heat 3. Room temperature increases ( ) 4. Negative feedback occurs as warmer air reaches the thermostat causing it to shut off 24 INPUT OUTPUT Control Center Stimuli Effector

Use a negative feedback loop to describe what happens when your body temperature drops 1. Body ( ) detects a drop in temperature ( ) 2. Brain ( ) sends messages in response to input 3. Heat is generated by muscles ( ) ; so temperature increases 4. 25

Negative Feedback Loop 26

Homeostasis ▪ Feedback Loops Continued Positive Feedback Loop: Not very common Examples: Blood clotting and giving birth of a baby Increases the original stimulus to push the variable farther; Think…MORE MORE MORE 27

Stretch receptors in wall of uterus send signals to the brain ( ) Childbirth Brain causes release of hormone ( ) Uterine smooth muscle contracts more forcefully ( ) More stretch, more hormones, MORE CONTRACTIONS ( ) Loop ends with birth of baby 28 stimulus control center effector

Positive Feedback Loop 29

Feedback ▪ Men experiencing labor Men experiencing labor ▪ And again....hehehe And again....hehehe 30