LBYZOOL Activity 01-04 (Lab Exam 1)

The Microscope, Animal Cell Structure, Membrane Transport, & Cell Division - Mitosis

Microscopy

term for any technique for producing visible images of structures or details too small to otherwise be seen by the human eye

Microscope

instrument used to magnify objects that can't be seen by the naked/unaided eye

Ocular / Eyepiece

the lens through which the object or the specimen is viewed

10x magnification

for Magnification

Revolving Nosepiece

holds and shifts the 4 objectives

feel the distinctive "click" as each objective is in proper position for viewing

for Support

Objective Lens

gives initial magnification

Scanning Lens / Scanner

4x magnification, red

Low Power Objective (LPO)

10x magnification, yellow

High Power Objective (HPO)

40x magnification, blue

Oil Immersion Objective (OIO)

100x magnification, white

Stage

flat surface where the slide/specimen is positioned

for Support

Aperture

round opening in the center of the stage

the slide/specimen is positioned over it

Stage Clips

holds the slide in place on the stage

Mechanical Stage

a type of stage that allows the slide to be manipulated by means of the 2 knobs located underneath it

Substage Condenser

condenses the light and focuses it on the specimen

lens under stage & specimen

for Illumination

Iris Diaphragm

controls the amount of light passing through the specimen

beneath the condenser

for Illumination

Substage Illuminator

source of light which illuminates the object being viewed

may be replaced by a mirror

for Illumination

Illuminator Control Knob

knob located on the side of the base below the mechanical stage adjustment knobs

controls the light output of the illuminator

Coarse Adjustment Knob

knob for focusing the Scanner and LPO

bigger movements

for Support

Fine Adjustment Knob

knob for focusing the HPO and OIO

smaller movements

for Support

Resolving Power

measure of lens quality

ability to deliver a clear image in fine detail

Field of View

size of the area that the lens views

higher magnification, smaller the area

Total Magnification

product of magnifications of eyepiece and objective lens

Parfocal Capability

ability of a microscope to stay relatively in focus as the user switches among objectives

Working distance

distance between the front of the microscope objective lens and the surface of the specimen

Image and Direction of movement under a Compound Microscope

Image:
appears upside-down & backward

Direction of Movement:
appears to be in opposite direction than actual movement

Stage Micrometer

glass slide etched with a scale of known units, usually divided into 0.01mm graduations

Ocular / Eyepiece Micrometer

circle of glass/plastic etched with non-unit scale ranging from 0 to 100

placed in ocular lens

Formula for Calibration Constant (mm)

( stage micrometer spaces / ocular micrometer spaces ) * 0.01mm

^multiply answer to 1000 when using micrometer (μm)

Dissecting microscope

a type of microscope used when magnifications between 5x and 50x are desired

used for small animals or body parts of larger animals

gives a 3D view of object

Cell

basic structure and functional unit of all organisms

basic unit of life

Cytology

study of cells

Prokaryotic Cell

type of cell:

small & simple
unicellular organisms
NO nucleus
LACK of membrane-bound organelles

Eukaryotic Cell

type of cell:

large & complex
unicellular or multicellular organisms
presence of nucleus
has membrane-bound organelles

Methylene Blue

dye used to stain nucleus, organelles, DNA, and RNA

Fusiform or Spindle-shaped Cell

an animal cell shape:

long, cylindrical, and tapered on both ends

seen in smooth muscle cells of a frog's stomach

Spherical-shaped Cell

an animal cell shape:

seen in the egg cells in a frog's ovary

Oval Shape

an animal cell shape:

seen in the red blood cells of a frog's blood smear

Amorphous Shape

an animal cell shape:

seen in the white blood cells of a frog's blood smear

Whip-like Flagella

an animal cell shape

threadlike appearance

seen in the sperm cells in the frog's testis

Homeostasis

constant internal environment

necessitates a constant entrance of materials into the cell and the passage of other substances out of it

Diffusion

type of membrane transport:

spontaneous movement of molecules of different substances

results from kinetic energy of the molecules

from higher concentration to lower concentration of the solute

until substance is equally distributed

Rate of Diffusion

increases with HIGH temperature and LOW molecular weight and size

Diffusion Rate (Gas) Experiment

glass tube with HCl and NH4OH at both ends, forming a white ring made of H2O and NH4Cl

Diffusion Rate (Liquid) Experiment

Congo Red, Methylene Blue, and Potassium Permanganate in solidified agar media

Diffusion and Temperature Experiment

Potassium Permanganate in beakers with hot and cold water

Diffusion and Molecular Size Experiment

Cellulose sac with starch solution placed in beaker with iodine solution, producing a blue-black color in the sac

Osmosis

diffusion of water through a semi-permeable membrane

high to low concentration of WATER

from a dilute solution to a concentrated one

Dialysis

process of diffusion of crystalloid solute through a semi-permeable membrane

Rate of Osmosis Experiment

5 sacs and 4 beakers with water and 1 beaker with sucrose

NEGATIVE % change in weight for sac E

Graph of % change in weight vs sucrose concentration

concave-like downwards

Facilitated Diffusion

type of passive transport:

movement of specific molecules across the cell membrane with the help of a transport proteins

Active Transport

type of membrane transport:

moves substances AGAINST their concentration gradients

requires energy (ATP)

Sodium Potassium pump

Example of Active Transport

Isosmotic

equal concentrations of solute in & out of cell

Hypoosmotic

less concentration of solute outside of the cell

water will enter cell

cell will swell & burst

Hyperosmotic

greater concentration of solute outside

water will leave the cell

cell will shrivel

2 Main stages of the Cell Cycle

Interphase and Mitosis

Interphase

longest phase of the cell cycle (90%)

composed of G1, S, and G2 phases

Chromatin

thread-like genetic materials inside the nucleus

Nucleoli

1-2 in nucleus

dense, darkly stained bodies formed by several chromosomal materials that code for certain RNAs

G0 phase

phase when cells become non-dividing

Centrosome

organelle near the nucleus that contains centrioles

Prophase

mitotic phase wherein:

chromatin condenses into chromosomes

centrioles with asters in opposite poles of the cell

mitotic spindles form between centrioles

nuclear membrane & nucleoli disappear

Asters

ray-like microtubule bodies around centriole

Metaphase

mitotic phase wherein:

chromosomes line up in the _______ Plate / Equatorial Region

spindle fibers attach to the centromere of each chromosome

Kinetochore

protein complex around the centromere of a chromosome

Centromere

region of each chromosome where the chromatids are held together to form an X shape

Kinetochore microtubules

mitotic spindles that get longer & attach to the chromosomes' kinetochores

Nonkinetochore microtubules

spindles NOT attached to chromosome

elongate the cell

Anaphase

mitotic phase wherein:

sister chromatids are pulled toward the opposite poles and will be considered as daughter chromosomes

Telophase

mitotic phase wherein:

the cell has a cleavage furrow

nuclear membrane and nucleolus reappear

chromosomes uncoil

Cleavage furrow

constriction of plasma membrane at the equatorial plate

Cytokinesis

division of the cytoplasm

Karyokinesis

division of nucleus

formation of 2 nuclei for the 2 daughter cells

Diploid

2 sets of chromosomes

2 daughter cells with 46 chromosomes each

Meiosis

division of sex cells (sperm and egg cells)

contains the formation of chiasma

result in 4 daughter cells

haploid (23 chromosomes each)

Haploid

1 set of chromosomes

23 chromosomes per cell

Chiasma

site of crossing over of 2 chromatids from homologous chromosomes

Whitefish Blastula

this animal's embryo is constantly dividing its cells so each stage of the cell cycle is easily observed