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Flashcards in Cells Deck (56)
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1

smaller units combined to make larger units

Hierarchy

2

Life originating from non-living material

ex. garbage --> rats
rotting food --> flies
mud --> frogs

Spontaneous Generation
(Abiogenesis)

3

life originating from life

Biogenesis

4

*microscope
*sends light thru object
*image is inverted

Compound Light Microscope

5

*microscope
*bounces light off object
*object has same orientation as on stage

Dissecting Scope

6

*microscope
*electrons are passed thru thin sections of object
*higher magnification due to resolution
*non-living material only

Transmission Electron Microscope

7

*microscope
*electrons are bounced off the object's surface
*non-living material only

Scanning Electron Microscope

8

*year
*cell theory created by Schleiden + Schwann

1838

9

*year
*cell theory created by Virchow

1858

10

*year
*Pasteur disproves spontaneous generation; proves biogenesis

1865

11

Scientist:
Hooke

*discovered and coined the term "cells"
*developed 1st microscope

12

Scientist:
van Leeuwenhoek

1st to observe and describe micro organisms which he referred to as "animalcules"

13

Scientist:
Aristotle

one of the first scientists to believe spontaneous generation did NOT occur in higher level organisms

14

Scientist:
Redi

disproved spontaneous generation (by observing maggot development in opened and closed meat containers) but was DENIED by scientific community

15

Scientist:
Needham

thought to have proved existence of spontaneous generation but used erroneous method (with errors)

16

Scientist:
Spallanzani

redid Needham's experiment correctly to disprove spontaneous generation

17

Scientists:
Schleiden + Schwann

created cell theory that states all life is composed of cells

18

Scientist:
Virchow

created cell theory that states all cells come from pre-existing cells

19

Scientist:
Pasteur

*credited with disproving spontaneous generation
*created flask that gathered microbes in neck

20

Scientist:
Margulis

created endosymbiont hypothesis

21

Scientists:
Uzzell + Spolsky

created membrane invagination hypothesis

22

Compare + Contrast:
Prokaryotic vs. Eukaryotic

BOTH --> types of cells

PRO --> does NOT contain a membrane bound nucleus
-Kingdom Monera

EUK --> contains a membrane-bound nucleus
-Kingdom Protista, Fungi, Plantae, Animalia

23

Compare + Contrast:
Endosymbiont vs. Membrane Invagination Hypothesis

BOTH --> refer to the origin of the eukaryotic cell

ENDO --> accepted; larger cell engulfed a smaller, simpler cell which became the membrane-bound nucleus

MEMB --> rejected; membrane folded in on itself and produced membrane-bound organelles

24

Major Cell Structures + Functions
(4)

1. Cell Wall - found in plants, algae, and prokaryotes only

2. Cell (plasma) Membrane - found in all cells, outer boundary of cell that separates internal processes from environment, contains receptors for external molecules that alter cell's function

3. Cytoplasm - found in all cells, portion of cell outside of nucleus, contains organelles

4. Nucleus - found in eukaryotes only, control center of cell, contains genetic material (DNA)

25

Cell Structures:
Protoplasm

*colorless substance that is the living part of cells
*contains cytoplasm and nucleus

26

Fluid Mosaic Model

According to this model, a membrane is...
- a double layer of proteins and phospholipids
- fluid (rather than solid)

27

Scientists:
Singer + Nicolson

developed the Fluid Mosaic Model

28

Transmembrane Proteins

*permanently attached to membrane
*span entirety of membrane
*function as gateways to permit transport of specific substances across membrane

29

Peripheral Proteins

*membrane proteins temporaily attached to the outer membrane surface

30

Phospholipid Bilayer

two layers of phospholipid molecules