1. To investigate cells macroscopically
Agenda: 2/19
Homework: Thursday – Lab notebooks with Dissecting Egg
Friday Test: Cell function & structure
To investigate cells macroscopically
After the lab
Cells – structure and function
Presentation
Video

2. “Dissecting a “Cell” and Examining Its Components
Lab procedures pp
Biotechnology Laboratory Manual
Ellen Daughtery

3. After Lab Review

4. “Dissecting a “Cell” and Examining Its Components
What do you think these eggs represent?
(Sized to scale)
A bird ovulates a single egg cell at a time.
The egg cell is what we call the yolk.
Most eggs are too small to be seen without the aid of a microscope.
However, we can study the chicken egg macroscopically.

5. Composition of a chicken egg

6. SHELL
Bumpy and grainy in texture, an eggshell is covered with as many as 17,000 tiny pores. Eggshell is made almost entirely of calcium carbonate (CaCO3) crystals. It is a semipermeable membrane, which means that air and moisture can pass through its pores. The shell also has a thin outermost coating called the bloom or cuticle that helps keep out bacteria and dust.
INNER AND OUTER MEMBRANES
Lying between the eggshell and egg white, these two transparent protein membranes provide efficient defense against bacterial invasion. If you give these layers a tug, you’ll find they’re surprisingly strong. They’re made partly of keratin, a protein that’s also in human hair.
ALBUMEN
The egg white is known as the albumen, which comes from albus, the Latin word for “white.” Four alternating layers of thick and thin albumen contain approximately 40 different proteins, the main components of the egg white in addition to water.
CHALAZAE
Opaque ropes of egg white, the chalazae hold the yolk in the center of the egg. Like little anchors, they attach the yolk’s casing to the membrane lining the eggshell. The more prominent they are, the fresher the egg.

7. VITELLINE MEMBRANE
The clear casing that encloses the yolk.
YOLK
The yolk contains less water and more protein than the white, some fat, and most of the vitamins and minerals of the egg. These include iron, vitamin A, vitamin D, phosphorus, calcium, thiamine, and riboflavin. The yolk is also a source of lecithin, an effective emulsifier. Yolk color ranges from just a hint of yellow to a magnificent deep orange, according to the feed and breed of the hen.

8. Main constituents (%) of edible part of a medium chicken egg: (Total caloric value 77 Kcal)
White %
Yolk
Protein
10.9
16.5
Fats
trace
32.0
Carbohydrates
1.0
Water
87.0
49.0

9. Nutrient content of large egg

10. Carbohydrate
Definition
Any of the group of organic compounds consisting of carbon, hydrogen, and oxygen, usually in the ratio of 1:2:1, hence the general formula: C H2 O. Examples include sugar, starch, cellulose and gums.

11. Indicator Tests Biology Labs ~ KCC Distance Learning Object
Indicators: solutions that change color in the presence of another type of molecule
Positive test
Negative test – no color change

12. Lugol’s Iodine Solution for Starch
Turns from yellowish brown to blue-black in the presence of starch

13. Biuret indicator for protein Interpret the colors
Observations and Interpretation
                                                                                                                                   
Biuret indicator for protein Interpret the colors

14. Biuret indicator for protein
Observations and Interpretation
                                                                                                                                   
Biuret indicator for protein
Positive test: blue to purple = protein presence
blue to pink = amino acids (building blocks of proteins
Negative test: remains blue

15. Class notebook Date Topic Page 2/10 Inside the Cell – Table
What is a cell? Notes from video & presentation
2/11
Warm-up: Probe: Speculation on what happened
2/19
Types of cells- prokarylotic & eukaryotic
compare plant & animal cells
Cells Structure and Function - Organelles
Voyage into the cell – video notes

16. Cell Structure & Function

17. Cell Theory All living things are made up of cells.
Cells are the smallest working units of all living things.
All cells come from preexisting cells through cell division.

18. Definition of Cell
A cell is the smallest unit that is capable of performing life functions.

19. Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell
Nerve Cell

20. Prokaryotic Eukaryotic
Two Types of Cells
Prokaryotic
Eukaryotic

21. Prokaryotic Do not have structures surrounded by membranes
Few internal structures
One-celled organisms, Bacteria

22. Eukaryotic Contain organelles surrounded by membranes Plant Animal

23. How do plant and animal cells differ?
Examine the following slides. Compare and contrast the cells.

24. “Typical” Animal Cell

25. “Typical” Plant Cell

26. Cell Parts
Organelles

27. Surrounding the Cell

28. Cell Membrane
Outer membrane of cell that controls movement in and out of the cell
Double layer

29. Cell Wall Most commonly found in plant cells & bacteria
Supports & protects cells

30. Inside the Cell

31. Nucleus Directs cell activities
Separated from cytoplasm by nuclear membrane
Contains genetic material - DNA

32. Nuclear Membrane Surrounds nucleus Made of two layers
Openings allow material to enter and leave nucleus

33. Chromosomes In nucleus Made of DNA
Contain instructions for traits & characteristics

34. Nucleolus Inside nucleus Contains RNA to build proteins

35. Cytoplasm Gel-like mixture Surrounded by cell membrane
Contains hereditary material

36. Endoplasmic Reticulum
Moves materials around in cell
Smooth type: lacks ribosomes
Rough type (pictured): ribosomes embedded in surface

37. Ribosomes Each cell contains thousands Make proteins
Found on endoplasmic reticulum (ER) & floating throughout the cell

38. Mitochondria
Produces energy through chemical reactions – breaking down fats & carbohydrates
Controls level of water and other materials in cell
Recycles and decomposes proteins, fats, and carbohydrates

39. Golgi Bodies Protein 'packaging plant' Move materials within the cell
Move materials out of the cell

40. Lysosome Digestive 'plant' for proteins, fats, and carbohydrates
Transports undigested material to cell membrane for removal
Cell breaks down if lysosome explodes

41. Vacuoles Membrane-bound sacs for storage, digestion, and waste removal
Contains water solution
Help plants maintain shape

42. Chloroplast Usually found in plant cells Contains green chlorophyll
Where photosynthesis takes place

43. Voyage Inside the Cell

44. Cells 101: Business Basics
Inside the Cell
Read and take Cornell notes

45. Using a Light Microscope to Study Cells
A light or compound microscope used light and 2 or more lenses to enlarge and focus on an image.
The eyepiece contains the ocular lens
Magnifies 10X
The rotating lenses are 4X, 10X, 40X & 100X
What magnification can be achieved?

46. Parts of the Microscope
See your notes: diagram and function