Cell Anatomy

Question 1

What is cell theory

Answer 1

-the cell is the smallest structural and functional living unit

Question 2

what do the organismal functions of cells depend on

Answer 2

-individual and collective cell functions

Question 3

what are the biochemical activities of cells dictated by

Answer 3

-their specific subcellular complementarity
-e.g. form dictates functions… anatomy leads to physiology

Question 4

what are the two basic cell types

Answer 4

Prokaryotes: single-celled organisms
Eukaryotes: Present in milti- cellular organisms (make us up

Question 5

what are the functions of cells

Answer 5

-Metabolize and release energy
-Synthesize molecules
-Reproduction and Inheritance
-Provide a means of communication

Question 6

how do cells metabolize and release energy

Answer 6

-chemical reactions that occur within cells
-release of energy in the form of ATP helps maintain body temperature

Question 7

how do cells synthesize molecules

Answer 7

cells differ from each other because they synthesize different kinds of molecules (create proteins and hormones)

Question 8

how do cells Provide a means of communication

Answer 8

-(neurons communicate w/rest of body
achieved by chemical and electrical signaling

Question 9

how do cells provide reproduction and inheritance

Answer 9

Mitosis- division resulting 2 identical daughter cells
Meiosis- creates egg and sperm cells (4 different daughter cells) still divides the cells

Question 10

what three basic parts of a human cell

Answer 10

-plasma membrane: flexible outer boundary
-intercellular fluid (cytosol) containing organelles
- cytoplasm

Question 11

what is the plasma membrane and what does it do

Answer 11

-Bimolecular layer of lipids and proteins in a constantly changing fluid mosaic
-Plays a dynamic role in cellular activity
-Separates intracellular fluid (ICF) from extracellular fluid (ECF)
-Interstitial fluid (IF) = ECF surrounding cells

Question 12

Describe membrane lipids

Answer 12

75% phospholipids (lipid bilayer):
5% glycolipids:
Lipids with polar sugar groups on outer membrane surface
20% cholesterol:
Increases membrane stability and decreases mobility
The more cholesterol the less movable the membrane is

Question 13

what are the 3 membrane junctions

Answer 13

-Tight junction
-Desmosome
-Gap junction

Question 14

what are tight junctions

Answer 14

-Impermeable junctions prevent molecules from passing through the intercellular space
-Found in the skin or the GI tract

Question 15

what are desmosomes

Answer 15

-Anchoring junctions bind adjacent cells together and help form an internal tension-reducing network of fibers.
-Difficult to pull apart but there could still be space, we would find this in the muscles and in the skin

Question 16

what are gap junctions

Answer 16

Communicating junctions allow ions and small molecules to pass from one cell to the next for intercellular communication allows one cell to communicate with another

Question 17

what is cytoplasm

Answer 17

-Between plasma and nucleus
Cytosol:
Water with solutes, proteins, salts, sugars, etc
Cytoplasmic organelles:
Metabolic machinery of cell

Question 18

what are the membranous organelles

Answer 18

-Mitochondria
-Endoplasmic reticulum
-Golgi apparatus
-Lysosomes
-Peroxisomes
-Membranes allow compartmentalization, crucial to cell function

Question 19

what is the mitochondria

Answer 19

-the powerhouse of the cell
-Double-membrane structure
-Provide most of cell’s ATP via aerobic cellular respiration
-ATP=molecule that stores and releases energy
-Contain their own DNA and RNA

Question 20

what are the ribosomes and the different types

Answer 20

-Granules containing protein and rRNA
-Site of protein synthesis
Types:
-Free ribosomes - synthesize soluble proteins
-Membrane-bound ribosomes (on rough ER) - synthesize proteins to be incorporated into membranes or exported from cell

Question 21

what is the endoplasmic reticulum and the two different types

Answer 21

-Interconnected tubes and parallel membranes enclosing cisternae
Continuous with nuclear membrane
Two varieties:
1. Rough ER- synthesizes membrane integral proteins and phospholipids. Manufactures all secreted proteins
2. Smooth ER

Question 22

what are the lysosomes

Answer 22

-the trash cans
-Spherical membranous bags containing digestive enzymes (acid hydrolases)
-digest ingested bacteria, viruses, and toxins
-degrade nonfunctional organelles
-Break down and release glycogen
-Break down bone to release Ca2+
-destroy cells in injured or non-useful tissue (autolysis)

Question 23

what are peroxisomes

Answer 23

-the recycling bin
-Membranous sacs containing powerful enzymes (e.g.,oxidases and catalases)
-Detoxify harmful or toxic substances
-Neutralize dangerous free radicals (highly reactive chemicals with unpaired electrons)

Question 24

What is the nucleus

Answer 24

-genetic library with blueprints for nearly all cellular proteins
-Responds to signals and dictates kinds and amounts of proteins to be synthesized
-Most cells are uninucleate
-Red blood cells are anucleate

Question 25

what is the nuclear envelope

Answer 25

Double-membrane barrier containing pores (large molecule transport)

Question 26

what is the nucleoli

Answer 26

-Dark-staining spherical bodies within nucleus
-Involved in rRNA synthesis and ribosome subunit assembly