Presentation on theme: "What type of tissue is composed of cells embedded in a matrix? a) nervous b) epithelial c) muscle d) connective e) None of the above are."— Presentation transcript:
What type of tissue is composed of cells embedded in a matrix? a) nervous b) epithelial c) muscle d) connective e) None of the above are correct.
Which of the following is a main benefit of multicellularity? a) Each cell can perform all of the necessary physiological processes needed by the body. b) Each cell can dump its waste directly into the environment. c) Only some body cells need to make ATP. d) Cells can divide up the labor of performing essential physiological processes. e) Each cell has direct access to nutrients in the environment.
Different types of tissues working together for a common function = organ Different organs working together for a common function = organ system
Which organ system(s) control or regulate body activities? a) nervous system b) endocrine system c) circulatory system d) immune system e) Both a) and b) control or regulate body activity.
What is the function of the respiratory system? a) exchange gases between the internal and external environment b) recycling fluids that leak from the circulatory system c) transport gases to and from tissues in the body d) make ATP from glucose and other energy-rich molecules e) purify the blood by filtering out wastes
2 main functions: › Maintains the proper water balance for body › Cleans blood of waste bi-products
The diffusion of water across a semi- permeable membrane Why should we care? › Our cells are sacs with semi-permeable membranes › Without the proper balance of water in cells, life systems shut down
Water will move from a dilute solution to a concentrated solution
Demonstrated in the last slide Concentration of solutions relative to adjoining solutions (one cell to the next cell or body relative to surroundings, etc.) Ex. Red Blood Cell in different solutions ABC
Different environments present different problems › Marine – tendency to gain salt + lose water › Freshwater – opposite – gain water, lose salt › Terrestrial – dry – very hypertonic Humans drink 2300 ml/day get 200 from metabolism gain 2500 Urinate1500 ml/day Lost due to evaporation: 1000 ml/day
Physical barriers to water movement › Scales on fish, cuticle, hair, feathers Pump water or salt from body › Urinate, flame cells of Planaria › Salt glands of marine birds and reptiles Pump water or salt into body › Drink › Freshwater fish have gill pumps that take in salt and concentrates it in the blood
Waste – what is it? › Ammonia (NH 3 ) is the most toxic Biproduct of protein breakdown If eliminated in its pure form – needs to be with lots of water – ex. Freshwater animals If terrestrial and need to conserve water – Ammonia is changed to a less toxic form Chemical change requires energy Urea – 2 ammonia + CO 2 (fish, amphibians, mammals, some invertebrates) Uric Acid – ring structure = powdery product (terrestrial organisms in dry locations)
Single celled animals – contractile vacuoles Earthworms – tube with cilia filters coelomic fluid and blood vessels associated with tube give off waste from blood
Body has different fluid compartments: › Blood - 5% body wt › Interstitial -15% body wt (lymph collects and returns to blood) › Intracellular (inside cells of body) – 50% body wt
Nephron 1 million/kidney
1.Filter blood 2.Secrete molecules/ions into nephron 3.Reabsorb some ions/molecules 4.Regulate amount of water lost 5.Eliminate urine
Secretion (2) › Selective (requires energy) transport of additional molecules in blood into proximal tubule Reabsorption (3) › Selective (requires energy) transport of needed substances back into blood › Most of water, solutes such as sodium, amino acids and glucose
Osmoregulation (4) › Loop of Henle › Salt gradient in cortex and medulla of kidney Medulla high conc Water removed from tubes Bottom of loop – inside tube = hypertonic Upward arm of Loop – membrane not permeable to water Salts pulled out More water pulled out through wall of collecting duct
Distal Tubule (2 +3) › Drugs and toxins removed from blood › Again much by active transport (requires energy) Collecting Duct › Eliminates urine (5)
a) Bowman’s capsule, proximal tubule, loop of Henle, distal tubule, collecting duct b) Loop of Henle, Bowman’s capsule, proximal and distal tubules, collecting duct c) Proximal tubule, loop on Henle, distal tubule, collecting duct, Bowman’s capsule
Drop in blood pressure detected by heart sensors Sensor information stimulates hypothalamus to secrete ADH ADH makes collecting ducts more permeable to water More water reabsorbed and retained by body, blood volume increases, blood pressure increases
________________ gain most of their heat from their environment, while _________________ can use metabolic heat to regulate their body temperature. a) Endotherms; ectotherms b) Plants; animals c) Fungi; animals d) Birds, lizards e) Ectotherms; endotherms
Which is the correct order of the processes used by the kidney in forming urine? a) reabsorption > filtration > excretion b) filtration > reabsorption > excretion c) excretion > filtration > reabsorption d) filtration > excretion > reabsorption e) excretion > reabsorption > filtration