Q1. How does your chromatogram differ from one that another group did with a different plant? How are they similar? Q2. pigments fluoresce? What colour does each of the fluorescent pigments appear under UV light? Q3. How can you explain the presence of colours on the chromatogram that are absent in the original leaf? Q4. Explain how you would account for the differential rates of migration of the various pigments using specific examples. What is the principle behind the separation? LABORATORY EXERCISE 5: Anatomy Laboratory Exercise 5: Plant Anatomy In this lab you will examine several types of plant tissue under the microscope. Part A: Pre-Lab Quiz Questions. (5 points) Lab 5 Pre-Lab Quiz Questions In your own words, define each of the following terms. Apical bud Axillary bud Collenchyma Cotyledon Ground tissue Meristem Parenchyma Petiole Phloem Sclerenchyma Sclerid Xylem Part B: Lab Protocols. 1) Primary growth and development Plants produce new throughout their lifetime as a result of cell division in meristems. Tissues produced by apical meristems are called primary tissues, and this growth is called primary growth. Primary growth occurs along the plant axis at the shoot and root tip.
Simple lungs evolved some 450 million years ago in fish. Some evolved into swim bladders and other evolved into more complex structures we call lungs. Paired lungs are the respiratory surfaces in all reptiles (including birds) and mammals. The amphibian lung is a simple, convoluted sac. The lungs are small and do not contribute to the majority of gas exchange. Instead, the skin performs most of the respiration in these animals. Reptiles and mammals do not use the skin as a primary respiratory surface and instead possess lungs with numerous alveoli. Diffusion of gases occurs across the alveolar surface. RAT Obtain your specimen of the rate used in the digestion and circulatory system labs. Open the mouth of the rat wide enough to expose the tubes leaving the pharynx by cutting through the skin, muscle and bone on both sides of the jaw. Locate the external nostrils and the pathway of air from here into the pharynx. the neck region, locate the trachea. Note the position of the trachea relative to the esophagus and note the differences in their structures and how these differences correlate to their functions. Follow the trachea in a posterior direction it branches into two bronchi, each of which enters one of the two lungs. Make a longitudinal cut through one lung to see the branches of a bronchus. Examine the dissected rat lung under the dissecting microscope. Can you see the alveolae? SKETCH what you see, and include it with your lab report. FROG: Obtain your frog. Remove one lung, and make a lateral incision, cutting it in half. Examine it under the dissecting microscope. Can you see the alveolae? Which type of lung, rat or frog, has the greater amount of alveolae per unit area? SKETCH what you see, and include it with your lab report. PIG: Observe the fresh lung of a pig and observe its texture. Locate a bronchus and trace it as far as you can by carefully cutting along its path. Appreciate the fine structure of the lung; a series of tubes terminating in microscopic sacs called alveoli. Locate the various divisions of the bronchi: primary, secondary and tertiary. HUMAN:
Which part of the human kidney has a higher concentration of urea, the renal cortex or the renal medulla? Where is urine collected in the human kidney before it enters the ureter? What is the name of the microscopic tubes in which sperm cells are formed in a teste? (Answer in the lab protocol.) When you are dissecting a female rat, or any other female mammal, what is one easy way to distinguish the uterus from the urinary bladder? (Answer in the lab protocol.) Part B: Lab Protocols. The Renal (Kidney) System: Cells produce water and carbon dioxide as by-products of metabolic breakdown of sugars, fats, and proteins. Chemical groups such as nitrogen, sulfur and phosphorus must be stripped from the large molecules to which they are attached as part of preparing them for energy conversion. The continuous production of metabolic wastes establishes a steep concentration gradient across the plasma membrane, causing wastes to diffuse out of cells and into the extracellular fluid. Single-celled organisms have most of their wastes diffuse out into the outside environment. Multicellular organisms, however, and animals in particular, must have a specialized organ system to concentrate and remove the wastes from the interstitial fluid. These wastes are moved into the blood capillaries and eventually deposited at a collection point for removal entirely from the body. Excretory systems serve this purpose. In animals, this system regulates the chemical composition of body fluids by removing metabolic wastes and retaining the proper amounts of water, salts, and nutrients. MAMMALIAN KIDNEYS The Rat: Obtain your rat from last time. With the help of the following diagrams, identify the following structures. (You may have to cut further down into the abdomen than you already have to expose these structures.) Abdominal Renal arteries Renal veins Kidneys Ureters Urinary bladder Ovaries (female) Uterus (female) Seminal vessicles (male) Prostate gland (male) Vas deferens (male)