Lab Question Answers

Lab 1

1. How many layers of cells are there in an Elodea leaf? 2 or 3

2. How should a coverslip be applied to a drop of liquid on a microscope slide? 45’angle

3. When chloroplasts appear to be moving within a living cell, what is the cause of their movement called? cyclosis

4. In most living cells, such as those of Elodea, where is the cytoplasm located? How extensive are plant cell vacuoles? l Along the edges of the cell, with the greater portion (up to 90%) of volume occupied by one or two central vacuoles

5. What are cytoplasmic bridges? Narrow stretches of cytoplasm that criss-cross the central vacuole

6. What parts of cells are normally visible with the aid of a compound light microscope? Nucleus, nucleolus, chloroplast, chromoplasts, other plastids, cell wall, mitochondria are barely visible in good light microscopes

7. If present in a cell, where are anthocyanin pigments located? . In the cell sap within vacuoles, gives red, blue or purple color to flowers and some leaves

8. How are starch grains distinguished from parenchyma cells in a potato? .  Grains are located within cells, may exhibit concentric rings, often several are located within a given cell.  Will stain darkly with iodine

9. What are striae, and where are they located in a spiderwort stamen hair cell? . Fine lines that are roughly parallel and are located on the cell surface

10. How does a chromoplast differ from a chloroplast? .  Primarily by the green color of chlorophyll in the chloroplasts. Stern text says they can be of similar size

The Cell

1. In what part of a cell are chloroplasts located?  cytoplasm

2. What is cyclosis? Cytoplasmic streaming, the movement of the cytoplasm and inclusions in it

3. What is a vacuole? Enclosed chamber within the cell. The boundary is a vacuolar membrane (tonoplast) that is generally not directly visible in light microscopes

What is the thin boundary of the vacuole called?tonoplast Is it visible? no

4. Where would you look for the nucleus in an Elodea cell? Along the edge of cell or nestled in a corner, they tend to be grayish, oblong and large (relative to other cell structures)

5. Anthocyanin pigments and chromoplasts may both be red in color. If you were to observe a cell that had both, how could you distinguish between them? The anthocyanin pigments are water soluble; while the contents of the chromoplasts tend to be lipid soluble

6. How can you tell a potato starch grain from a cell? No cell wall, several grains are often found in each cell

7. How would you distinguish a starch grain from a chloroplast? Chloroplast will be green and have a fairly regular oval shape

8. What is a cytoplasmic bridge? Narrow strands of cytoplasm that tend to criss-cross the central vacuoles

9. Specifically where do starch grains develop in a cell? Inside leucoplasts (membrane bound plastids, especially amyloplastids), on pyrenoids of larger chloroplasts

10. Where would you expect to find a nucleolus? Inside the nucleus, often appears to be a darker region within it


Optional Exercise


2. Normal cell functions such as protein synthesis and respiration occur during which phase? Interphase

3. The duplication of DNA and chromatids occurs during which phase?  S Interphase

4. If a parent cell has 32 chromosomes, then after mitosis daughter cells each have how many chromosomes? 32

5. Contrast the telophase in animal and plant cells. Constriction-cleavage  vs cell plate




2. As potato cells are placed in solutions that are increasingly hypotonic, what tends to happen? swell

3. 20.0 gm of salt in 600.0 gm of solution is a what percent solution?  3%

4. How many gm of salt and how many gm of water are needed to make 300.0 gm of a 4.0 percent solution? 12 salt 288 water

5. 250.0 gm of a 2.0 percent salt solution contains how many gm of: 
                                 5   gm of solute


245 gm. of solvent


250 gm of solution


8. 20.0 gm of salt added to 200.0 gm of water is a what percent solution? 9%
Comparing two solutions with free diffusion.


SELECT ONE:                        a. isotonic solution


b. hypertonic solution


c. hypotonic solution


The water would move primarily into the  hypertonic solution

The solute would move primarily out of the hypertonic solution

The solvent would move primarily out of the hypotonic solution

 Movement of solute and solvent would continue until both solutions were isotonic


1. With which specific region of roots is this exercise concerned? Zone of maturation (differentiation)

2. In which tissues do the following originate?

Root hairs    epidermal/region of differentiation Lateral roots  pericycle

3. What evidence of the food-storage function of cortex is present in buttercup roots? Granules in cortex cells

4. Which tissue surrounds and borders the stele of a dicot root?the endodermis 

Which tissues comprise the stele? stele is comprised of pericycle, xylem and phloem

5. What is the function of the vascular cambium?  Usually develops between the primary xylem and phloem and produces secondary xylem and phloem

6. Of what substance are Casparian strips composed? Bands of fatty suberin

7. Is a pith present in all roots? no  If not, in which roots is it present? monocot

8. As lateral roots develop inside a primary root, through which tissues must they grow to reach the surface ? Through the endodermis, cortex and epidermis (although epidermis of lateral root becomes continuous with epidermis of primary root 


1. From which tissue do lateral roots arise? pericycle

2. Between which tissues is the vascular cambium located? Between primary xylem and phloem

3. Which tissue of stems is not present in dicot roots? Pith

4. In which tissues are root hairs to be found?  epidermal

5. Which tissue is immediately adjacent to the endodermis on the side toward the center? Pericycle

6. In which region of the root does differentiation of cells into various cell types take place? Zone of maturation

7. What is present in cells of the cortex that gives evidence of its function as a food-storage tissue? Granules  

8. Of what fatty substance are Casparian strips composed? suberin

9. What tissue produces cells that add to the girth (diameter) of the root? Vascular cambium

10. What water-conducting tissue is present in the center of a dicot root? primary xylem





1. What protects the buds of dormant twigs?  Terminal Bud Scales

2. What are bundle scars?_ Sealed ends of vascular veins that led into petiole from stem.

3. Where, specifically, are axillary buds located? In the angle between the stem and the petiole of leaf

4. What structures associated with gas exchange are found throughout stem internodes? lenticles

5. What is the difference between bud scale scars and leaf scars? . Bud scale scars result in a series of narrow linear raised regions around the “stem”, usually one at start of each growing season; leaf scars are formed by the separation of leaf petiole from stem

6. Which tissue separates cortex from pith in an older alfalfa stem? What is the function of this tissue? The meristematic vascular cambium that gives rise to xylem and phloem


7. What is the primary function of cortex and pith? Storing and sometimes manufacturing food

8. Which tissue conducts water and minerals in solution?  xylem

9. If you saw cross sections of Begonia or Coleus and alfalfa stems side by side, what differences would be obvious? . The arrangement of the vascular bundles and the presence of a pith in the dicot stem

10. Which stains are used to make the tissues of your handmade linden (basswood) slide more readily visible? Gentian violet and eosin

11. If you wished to make your handmade linden (basswood) slide permanent, which additional substances would you use? Xylene and balsam

12. Which two tissues are produced by the cork cambium, and which two tissues are produced by the vascular cambium? Cork cambium produces cork and phelloderm

vascular cambium produces secondary xylem and secondary phloem



1. Where are axillary buds located? In the angle between petiole and stem

2. What are the small bumps of parenchyma tissue on the surface of the internodes called?lenticles

3. How is a bundle scar formed? When the leaf petiole separates from stem breaks a vascular vein

4. What is the function of a lenticel?  Gas exchange

5. Which of the stems in this exercise has the most complex phloem? basswood

6. What stains are used in making your own linden (basswood) slide? Gentian violet and eosin

7. In addition to cork, what tissue is usually produced by the cork cambium?phelloderm cells

8. How are vascular bundles arranged in a monocot stem Scattered through out the fundamental tissue, with the phloem oriented toward the outside

9. Which of the stems featured in this laboratory exercise is (are) NOT (a) dicot(s)?corn

10. To make your own microscope slide of a linden (basswood) stem permanent, what substance  would you add just before placing a coverslip on it? Balsam (xylene would be added before balsam)


Leaf Lab


1. How does a compound leaf differ from a simple leaf? Compound leaf’s blade has two or more separate leaflets attached to the end of a petiole or along a central ramis; simple leaf has a single undivided blade

2. What fatty or waxy substance present on the outer walls of leaf epidermal cells is usually lost in the preparation of slides? Fatty or waxy cuticle

3. When you view a cross section of a leaf with the upper epidermis at the top, where is the phloem located in a vein?in lower part of vein

4. Which of the larger organelles are most abundant in palisade mesophyll cells?chloroplasts

5. What specific tissue marks the outer boundary of transfusion tissue in a pine leaf?endodermis

6. Which tissue lies between the epidermis and the endodermis in a pine leaf? Mesophyll

7. Where are the resin canals located in a pine leaf?in mesophyll

What is their function? help protect from herbivores and pathogens

8. What are sunken stomata? Recessed openings for gas exchange; plants found in xeric and cold conditions,

With which types of plants are they associated?desert plants/pines

9. What is the function of a hypodermis? Reduction in water loss

Where is a hypodermis located? ; found below the epidermis of pine needles

10. Apart from size and shape, how do guard cells differ from the epidermal cells that surround them?contain chloroplasts


1. What are stipules? Pair of leaf-like or scale-like appendages on either side of petiole

2. What is the fatty or waxy substance that coats a leaf epidermis called?cuticle

3. What tissue composed of thick-walled cells is found just beneath the epidermis of a pine leaf?hypodermis

4. In prepared slides of lilac leaves, why are some veins visible in cross section while others are visible in longitudinal section? Veins branch out in leaf, so some are cut in cross section while others are cut longitudinally

5. Which tissue of pine leaves differs from that of lilac leaves in its not being divided into two distinguishable layers? Mesophyll not divided into palisade and spongy

6. Of which two tissues are leaf veins primarily composed? Vascular tissue—xylem and phloem

7. Where are stomata generally most abundant in the majority of leaves?lower surface

8. Which layer of mesophyll is closest to the upper epidermis of a leaf? Palisade mesophyll

9. In what kind of leaf would you expect to find resin canals? pine

10. The two cells that form and surround a stoma are known  as Guard cells




Seeds and fruit lab

1. What distinguishes a hesperidium from a pepo? Pepos have leathery rind-hesperidium has leathery skin that contains oil

2. Which of the fruit types is derived from more than one pistil     aggrigate-raspberry flower/fruit

3. How doe you tell a grain (caryopsis) from an achene? Achene is a fruit with 1 seed and seed is attached to it at any point, grain is single seed fused with the fruit wall

4. If you were to cut an apple in half, you would notice that the endocarp around the seeds is somewhat papery. How would you classify it as to fruit type?

5. Drupes and nuts both have a single seed. What distinguishes them from one another?nuts surrounded by hard case wall and drupe is enclosed in a pit

6. Black raspberries and mulberries look quite a bit alike, but raspberries are aggregate fruits while mulberries are multiple fruits. What is the difference? Raspberries have a bunch of small fruits formed from a single flower with many pistles

7. Choose one of the poisonous plants and tell which part or parts is(are) poisonous.

8. When you use oregano as a spice, what part of the plant is involved? leaves

9. Name two spices that are derived from flowers or flower buds. Nutmeg, cinnamon

10. Choose one of the survival  plants and tell how it is used.

1. Which fleshy fruits have a single seed enclosed in a hard pit? Olives, almonds

2. Strawberry flowers have numerous pistils on a common receptacle. What fruit type does that make them? accessory

3. How many seeds does a typical berry have? many

4. What distinguishes a hesperidium from a true berry? Berries have a fleshy wall and a hesperidium has a leathery skin

5. Do both aggregate and multiple fruits come from more than one pistil? Explain. Aggregates come from one pistle but multiple are laural flowers on the same plant

6. Give a common example of a fruit in which the seeds do not develop. Pineapple/banana

7. Which dry, splitting fruit has a central partition to which the seeds may be attached          pea

8. What type of dry, nonsplitting fruit has a wing at maturity?caryopsis

9. What type of dry, splitting fruit splits only along one edge?follicle

10. How do you tell a grain (caryopsis) from an achene?achene is a single seeded fruit in which the seed is attached to the pericarp only at its base           grain: a dried fruit in which the pericarp is tightly fused to the seed.


Moss and fern Lab


1. How do moss "leaves" differ from the leaves of more complex plants? No vascular tissue and are haploid

2. What is the difference between a calyptra and an operculum? Calyptra is haploid developing from archegonial material and covers the capsule as a “pixie cap”; operculum is diploid and covers the capsule over the peristome

3. How is the release of spores controlled in mosses? . Peristome’s membranous teeth in capsule change shape with changing conditions releasing the spores

4. Where does meiosis take place in mosses? Inside capsule

5. Where, in mosses, are zygotes and embryos formed? By fertilization inside archegonia

6. In Marchantia, what is the function of archegoniophores and antheridiophores? Archegoniophores and antheridiophores are the elevated holders of archegonia and antheridia, respectively.

7. What are all the parts of a complete sorus? Clusters of sporangia under an indusium

8. Where, specifically, are fern antheridia located? Among the rhizoids on prothallus

9. What parts of a fern are 2n? 2N:  Frond, rhizome, roots (also zygote and embryo)

  Where, in a fern, does the switch from 2n to n take place? Shift to haploid occurs in the sporangium in sorusWhere, in a fern, does the switch from n to 2n take place? Shift to diploid occurs with fertilization of egg in archegonium forming a zygote

10. In addition to seeds, what do higher plants have that bryophytes lack? Vascular tissue

11. Which phase in the life cycle of a moss consists of a "leafy" plant? Gametophyte

12. In which specific structure of a moss are sperms produced? . Antheridium

13. What is the toothed structure in a moss sporophyte that controls the release of spores from a sporangium? Peristome

14. How does a thalloid liverwort differ in appearance from a moss? Flattened bright green body with elevated structure (archegoniophores and antheridiophores) rather that the leafy structure of mosses

15. What is a cluster of fern sporangia called? Sorus

16. Where does meiosis take place in ferns? Sporangium

17. What name is applied to the gametophyte of ferns? . Prothallus

18. Where are fern antheridia produced (i.e., among what structures on the gametophyte)? Among the rhizoids

19. What are the differences among rhizoids, roots, and rhizomes? Rhizoids are anchoring structures; roots are anchoring and absorptive; rhizomes are underground stems

Gymnosperm lab

Questions 1. What does the term gymnosperm mean, and in what sense does it apply to pine trees? Naked seeds, they develop on surface of cone scale rather than being enclosed within a fruit.

2. Apart from size differences, how can you distinguish a cone scale of a pine seed cone from that of a pine pollen cone? The pollen cone scale is much more membranous (flexible) than seed cone scale

3. Of what does the female gametophyte of a pine consist? What other tissues surround it? The pollen cone scale is much more membranous (flexible) than seed cone scale

4. What is the function of a nucellus? Nutritive

5. What constitutes the sporophyte in a pine? The “tree” and the cones

6. Where, specifically, are pine pollen grains produced? In the microsporangia at base of pollen cone scale

7. What structure of a pine ovule develops into a seed coat? A portion of the integument

8. What do the pollen grains of pine trees have that aid in their dispersal by the wind? Wings

9. Could all the representatives of gymnosperms mentioned in this exercise be differentiated by their leaves alone? If not, why not and if so why? Yes, while the leaves of the Gnetophyta are rather heterogeneous in size and shape, the leaves of the others are distinct from those of Gnetophyta

1. What is the difference between a gymnosperm and an angiosperm? Gymnosperms seeds are naked (not enclosed within a fruit)

 2. How many seeds are produced at the base of each pine seed cone scale? Two

3. What specific cells of pine undergo meiosis? Microsporocytes produce microspores that form pollen grains;

What do these cells then become? megasporocytes produce the megaspores, one of which will form female gametophyte


4. Through what passage is a pollen grain of pine drawn prior to its full development into a mature male gametophyte? Micropyle

5. What is the space above the nucellus in a pine ovule called? Pollen chamber

6. From what specific cell does the embryo of a seed develop? Zygote

7. Where on a pine tree are pollen cones usually produced. Tips of lower branches

8. From what structure does the seed coat of a pine seed develop? Integument

9. Specifically, where are pine sperms produced? In male gametophyte (in pollen tube)

10. Which of the gymnosperms discussed has two straplike leaves? Welwitschia (a Gnetophyta)


angiosperm lab Review Questions 18

1.  Receptacle

2. Filament

3. Stigma

4. Four microspores that form pollen grains

5. Two (tube and generative); three (tube and two sperm)

6. Through micropyle

7. Pollination is the deposition of pollen grain on stigma, while fertilization involves the fusing of the sperm nucleus with the egg nucleus

8. Degenerate

9. One of sperm nuclei fuses with the two central nuclei; endosperm nucleus divides many times forming the endosperm tissue that surround embryo(in monocots forms part of seed; in dicots it becomes incorporated into cotyledons)

10. Integuments


Quiz 18

1. Inflorescence

2. Ovules

3. Synergids

4. The area through which the pollen tube gains access to the female gametophyte

5. Two

6. Sperm nuclei

7. Two central nuclei

8. Megasporocyte

9. In ovule

10. In megagametophyte

Plus All life cycles are fair game