Cell Structure (Chapter 4)

Question 1

What are the 2 types of microscopes?

Answer 1

Light Microscopes
-Use magnifying lenses with visible light
-Resolve structures that are 200 nm apart
-Resolution is limited by wavelength of light

Electron Microscopes
-Use beam of electrons
-Resolve structures that are 0.2 nm apart

Question 2

Cell Theory

Answer 2

-All organisms are composed of cells
-Cells are the smallest living things
-Cells arise only from pre-existing cells
-All cells today represent a continuous line of descent from the first living cells

Question 3

Rate of Diffusion is affected by

Answer 3

-Surface area available
-Temperature
-Concentration gradient
-Distance

Question 4

As a cell’s size increases,

Answer 4

It’s volume increases much more rapidly than it’s surface area

Question 5

Basic structural similarities between prokaryotes and eukaryotes

Answer 5

1. Nucleoid or nucleus where DNA is located
2. Cytoplasm
3. Ribosomes
4. Plasma Membrane

Question 6

Prokaryotic Cells

Answer 6

-Simplest organisms
-Lack a membrane-bound nucleus
-Cell wall outside of plasma membrane
-Do contain ribosomes
-Two domains of prokaryotes
-Archaea
-Bacteria

Question 7

Coccus, Bacillus, and Spirillum are

Answer 7

Three basic Primary Shapes

Question 8

Facts about Bacteria cell walls

Answer 8

-Most bacterial cells are encased by a strong cell wall composed of peptidoglycan
-The cell wall can be a target for antibiotics such as penicillin
-The cell wall is often covered with a capsule made of (lipo) polysaccharides

Question 9

Are used for locomotion

Answer 9

Flagella

Question 10

Pili

Answer 10

They exchange genetic material during conjugation

Question 11

Bacteria use _____ to attach to a host cell

Answer 11

Fimbriae

Question 12

Nucleoid Region and Ribosomes

Answer 12

-Contains the singular, circular chromosome. May also contain plasmids

-Smaller than those of eukaryotes. Differ in protein and RNA content. Targeted by some antibiotics

Question 13

Endospores

Answer 13

Some prokaryotes have the ability to develop a thick wall around their genome and a small portion of the cytoplasm when exposed to environmental stress. When conditions improve they can germinate and return to normal cell division.

Question 14

-Possess a membrane-bound nucleus
-More complex than prokaryotic cells
-Possess a cytoskeleton for support and to maintain cellular structure

Answer 14

Eukaryotic Cells

Question 15

Nucleus

Answer 15

-Repository of the genetic information
-Most eukaryotic cells possess a single nucleus
-Nucleolus - region where ribosomal RNA synthesis takes place
-Nuclear envelope
-2 phospholipids bilayers
-Nuclear pores-control passage in and out
-In eukaryotes, the DNA is divided into multiple linear chromosomes

Question 16

Ribosomes

Answer 16

-Cell’s protein synthesis machinery
-Found in all cell types in all 3 domains
-Ribosomal RNA (rRNA) - protein complex
-Synthetizes proteins based on messenger RNA (mRNA) code
-Ribosomes may be free in cytoplasm or associated with internal membranes

Question 17

Endomembrane System

Answer 17

-Series of membranes throughout the cytoplasm
-Divides cell into compartments where different cellular functions occur
-One of the fundamental distinctions between eukaryotes and prokaryotes