1 / 86

Topic 1: Body Organization

Topic 1: Body Organization. Zygote: fertilized cell created by the union of the egg and sperm >200 types of human cells Embryonic stem cells Created during earliest divisions Potential to become any type of cell. Determination. Determination

nassor
Download Presentation

Topic 1: Body Organization

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Topic 1: Body Organization • Zygote: fertilized cell created by the union of the egg and sperm • >200 types of human cells • Embryonic stem cells • Created during earliest divisions • Potential to become any type of cell

  2. Determination • Determination • Process where stem cells commit to a specific type • Few weeks into development • Irreversible

  3. Differentiation • Differentiation • Process where cells acquire the structures & functions of a specialized cell • Specific genes activated • Ex: Nerve cells grow dendrites

  4. Organization • Cell: Basic unit • Tissue: Group of cells • 4 types • Organ: Groups of tissue • Ex: lung contains each tissue • Organ System: Group of organs working together • Digestive System • Organism: all organ systems working together

  5. Muscle: contracting cells Skeletal, cardiac cells Body Tissues

  6. Connective Tissue: Support the body Bone, fat, tendons Body Tissues

  7. Epithelial: protection sheet of cells skin, stomach lining Body Tissues

  8. Nerve Tissue: Transmit electric signals Brain & Spinal Cord Body Tissues

  9. Topic 2: Homeostasis

  10. Homeostasis • Process where the body maintains a constant internal environment • Reactions & enzymes work best in specific conditions • Control systems adjust to internal/external changes • pH, temp, fluids • Constant internal environment maintained

  11. !*%!?%&# Control Systems • Sensors (aka: receptors) • Gather information about the body and environment • Ex: skin senses pressure • Communication Center • Messages sent throughout the body to respond • Ex: Impulse travel through your nerves • Control Center • Receives information from the sensors • Ex: Brain interprets the impulse • Targets • Body part that changes its activity • Ex: Muscles in foot stretch/contract abruptly

  12. Negative Feedback Loops • Regulates most of the body • Counters changes in the body that move conditions away from a set point • Reverses the change • Keeps internal environment stable

  13. Positive Feedback Loop • Increases the changes away from set points • Important when rapid changes needed • Ex: Oxytocin released • When uterus contractions begin, oxytocin released to speed up the contractions (not stop them)

  14. Working Together • Thermoregulation: Maintenance of body temperature • Skin: sensors provide feedback to brain • Nervous & Endocrine system: send messages to/from brain • Muscles: Start to shiver

  15. Homeostasis disruption • Sensors fail • Wrong messages sent • Message doesn’t reach target • Serious injury • Microorganism infection • Short Term • Temporary discomfort (usually)

  16. Long Term: Diabetes • Normal Cells • Glucose circulates in blood; pancreas releases insulin • High glucose levels: insulin opens gates of cells to allow glucose to enter • Glucose levels lowered • Type 1 Diabetes • Immune system destroys cells to produce insulin • Pancreas fails: no signal for gates to open = glucose accumulated in blood stream • Type 2 Diabetes • Low insulin production due to overworked pancreas • No signal for gates to open = glucose accumulated in blood stream

  17. Topic 3: The Nervous System

  18. Neurons • AKA: Nerve Cells • Transfer electrical impulses to/from the brain • 3 Main Parts • Cell body: contains nucleus and organelles • Dendrites: branches that receive messages from neighboring cells • Axon: extension that carries messages away from the cell body

  19. Resting Potential - - - - - - - - - - - - - - - - - - - - - - - - - - APPEAR/HIDE • Defined: Neuron at rest • Neuron Exterior: • Positive charge • Mainly Na+ outside the cell • Neuron Interior: • Negative charge (from various proteins) • K+ inside the cell

  20. Action Potential • Defined: Electrical impulse is triggered • Front end of impulse • Na+ enter the cell • Negative impulse attracted towards positive Na+ • Back end of impulse • K+ exits the cell • Interior returns to normal charge • Impulse pulled along by the changing of electrical charges

  21. impulse

  22. Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ K+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ K+ K+ Na+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ negative impulse K+ K+ K+ K+ K+ K+ K+ Na+ K+ Na+ K+ K+ K+ K+ K+ K+ Na+ K+ K+ K+ Na+ K+ K+ K+ K+ K+ K+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ K+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+

  23. Synapse • Defined: Gap between neurons • Problem: Impulse cannot cross the gap • Solution: Impulse converted into chemical molecules (neurotransmitters) • Steps: • Impulse reaches neuron’s end • Vesicle releases neurotransmitters • Neurotransmitters attach to neighboring neuron • New impulse created

  24. Impulse stimulates a vesicle, which contains neurotransmitters Vesicle exits the cell and dissolves impulse Start of another cell End of one cell

  25. Neurotransmitters stimulate a new impulse Neurotransmitters cross the synapse and attach to receptors of a neighboring neuron impulse impulse Start of another cell End of one cell

  26. Brain …. …. …. …. Feet

  27. Motor neurons reach the muscles Impulse causes the muscles to stretch and contract…this causes MOVEMENT!

  28. Topic 4: The Senses

  29. Eye Anatomy Cornea Protective layer of the eye Iris Colored part of the eye Contains muscles to open & close the pupil Pupil Size adjusts with light Small: more light Large: less light Lens Focuses light onto the retina Retina Back of the eye Contains rods & cones

  30. Vision Process 1) Light passes through pupil 2) Lens focuses light onto retina 3) Photoreceptors of the retina create impulses Impulse travels up optic nerve to brain #3 #2 #1

  31. Ear Anatomy Pinna Outer ear Eardrum Amplifies sound by 3 bones: malleus, incus, stapes Cochlea Contains mechanoreceptors (measures pressure)

  32. SoundTransmission 1) Sound waves (vibration of the air) enters the ear canal 2) Eardrum & the small bones vibrate 3) Fluid in the cochlea vibrates 4) Hair cells in the cochlea bend 5) Impulse transmitted through the auditory nerve and to the brain

  33. Smell & Taste Nose Scent chemicals dissolve in mucus Impulse travels from olfactory nerve to brain Tongue Chemicals dissolve in saliva Chemoreceptors in taste buds creates impulse

  34. Touch, Temperature, Pain Mechanoreceptors in skin sense pressure Upper layer: gentle touches Lower layer: heavy pressure Thermoreceptors & Pain receptors detect temps and chemicals released by damaged cells Impulses sent to brain

  35. Topic 5: The Immune System

  36. The Skin • 1st line of defense: physical barrier • Oils & sweat destroy some pathogens • Some cells burst • Some cells shrivel

  37. Mucus Membranes • Coat the openings of the body • Nose, mouth, ears, eyes, genitals, anus • Lined with cilia & sticky fluids to trap pathogens

  38. White Blood Cells • Job: Search & destroy • 1) Phagocytes: surround & engulf invaders by phagocytosis • 2) Lymphocytes: • T cells: destroy infected body cells • B cells: Inactivate invaders

  39. phagocyte bacteria phagocyte

  40. Defense Proteins • Complimentary Proteins • Weaken cell membrane • Attract phagocytes • Cause microbes to stick to wall of blood vessel

  41. Defense Proteins • Antibodies • Made by B cells • Stick to pathogens • Causes pathogens to clump • More susceptible to phagocytes • Weakens the cell membrane • Causes them to burst

  42. Defense Proteins • Interferon • Produced by virus infected cells • Stimulates uninfected cells to create infection preventing enzymes

  43. Prevents infections (not a cure) Memory cells developed without actually getting the disease Vaccine Contains antigens of a pathogen Weakened pathogen is injected Stimulates the production of memory cells Speeds up immune response if you encounter the unweakened virus Vaccination

  44. Topic 6: Blood

  45. Components of Blood Whole blood RBCs WBCs Platelets: cell fragments that aid in clotting Plasma 90% water (allows materials to dissolve) Amino acids, glucose, hormones, vitamins, salts, waste Concentrations allows diffusion in/out of blood stream

  46. Red Blood Cells Produced from stem cells in bone marrow Lose nucleus as they mature Transport O2 to cells O2 binds to hemoglobin proteins Dead cells filtered by liver & spleen

  47. Proteins on blood cells determined blood type Antigen (markers) proteins on cell’s surface that identify cells as foreign or natural Antibodies: proteins from WBCs to attack invaders Float freely in plasma ABO Blood Groups

More Related