Animal Form & Function

1. Animal Form & Function Chapter 40

2. Chapter 40 – Basic Principles • Cells  Tissues  Organs  Organ Systems • Tissues – groups of cells w/ common structure & function • Organs – groups of tissues w/ common structure & function • Organ System – group of organs that work together

3. 4 Types of Tissue • 1. Epithelial Tissue – covers or lines organs or the body • 2. Connective Tissue – supports & binds other tissue • 3. Muscle Tissue – responsible for body movement • 4. Nervous Tissue – responsible for sensing stimuli & response to the stimuli

4. ECMN • How will u memorize the 4 types of tissue?

5. Epithelial Tissue • 1. Epithelial Tissue • Covers the body, lines the organs, & acts as a protective barrier • One side is always bound to basement membrane • Underlying supportive surface • Other side faces air, environment or fluids

7. 3 Types of Epithelium • 1. Simple – 1 layer of cells • 2. Stratified – Multiple layers of cells • 3. Glandular – absorb or secrete chemicals (mucus, etc.) • Cells at the Exposed surface • Cuboidal – Like dice • Columnar – Like brick standing on end • Squamous – Like floor tiles

9. Connective Tissue (CT) • Supports & binds other tissues • Sparse population of cells scattered throughout an extracellular matrix • 3 Kinds of CT fibers • 1. Collagenous – collagen & inelastic (not demand) • 2. Elastic – long fibers made of elastin • 3. Reticular – collagen & continuous with collagenous fibers

11. Examples of Connective Tissue • Cartilage – shark skeleton – flexible – tip of nose, ears • Bone – not so flexible • Ligaments – connect bone to bone • Tendons – connect muscle to bone • Blood – since it has an extensive extracellular matrix • Loose connective tissue – most widespread • Adipose tissue – loose connective tissue that stores fats

13. Muscle Tissue • Skeletal – responsible for voluntary movements • Building muscles does not increase # of cells, but does enlarge the fixed number of muscle cells • Also called striated muscle • Smooth – responsible for INvoluntary movements • Arterial constriction, bowel movements • Lacks striations = smooth • Cardiac – heart muscle • Cardiac contractions • Striated like skeletal muscle

14. SKELETAL MUSCLE

15. SMOOTH

16. CARDIAC

18. Nervous Tissue • Functional unit is the neuron or nerve cells • Sense stimuli & transmit signals across the body • Transmit signals to other neurons, glands, muscles, & brain

20. 2 Important Systems • Coordination & Control • Endocrine System – responsible for hormone production • Hormones – chemical signals responsible for long-distance signaling • Hormones are released into the bloodstream • Bloodstream broadcasts the hormones throughout the body • Remember Signal Transduction Pathways? • Nervous System – transmit information between specific locations • Neurons, muscle cells, & endocrine cells

21. Homeostasis • Homeostasis is a key concept in animal physiology • Homeostasis – maintenance of a relatively constant internal environment • Set Point – reference point for homeostatic mechanism • Body has sensors that detect any deviation from the set point • If there is a deviation (+ or -), physiological response will return the body to the set point

22. Homeostasis Exercise • Find 2 biological examples of Homeostasis • Explain each of your 2 examples of homeostasis • Explain the effects of at least 2 deviations from the set point • 1 Positive deviation & 1 Negative deviation • Explain the homeostatic response mechanism for each of the deviations.

23. Feedback Systems • Negative Feedback System – Physiological response to a stimulus REDUCES the stimulus -- Exercise (Stimulus)  Body Temp Rises  Perspiration (body cooling) -- Air temperature decreases Shivering  Friction (body warming) • Positive Feedback System – stimulus elicits a response that amplifies the effect of the stimulus • Childbirth  increased pressure on opening of uterine wall   Stimulates increased uterine wall contractions  Greater pressure on opening of uterine wall

24. Negative Feedback Mechanism pp. 955 - BIOLOGY

25. Positive Feedback Mechanism pp. 981 - BIOLOGY

26. Thermoregulation • Thermoregulation – How animals maintain their internal temperature within a tolerable range • Endotherms – body warmed by heat generated by metabolism • Examples: birds & mammals • Ectotherms • Gain most of their heat from environment • Invertebrates, fish, amphibians, reptiles

28. Countercurrent Exchange • Reduction of heat loss depends on countercurrent exchange • Birds & Mammals • Antiparallel arrangement of blood vessels • Warm blood from the animal’s core goes to the extremities • This blood transfers heat to the colder extremities • Heat that usually is lost to environment is used to heat extremities