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Flashcards in Cells and organelles Deck (51)
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1

Definition of a cell

Semi independent, living unit within body (completely independent in unicellular)
Site of metabolism mechanisms, growth, replication
Made up of aqueous solution of organism molecules, membrane bound

2

Definition of an organelle

Subunit within cell
Defined structure w specific integrated activities
Not all are membrane bound

3

Definition of a tissue

Organized assembly of cells and extracellular products
Carry out similar, coordinated activities in body

4

Definition of an organ

Assembly of tissues, coordinated to perform specific body functions

5

Definition of a system

Assembly of organs w specific, related activities, sharing regulatory influences
Can be a diffuse functional network of cells situated in many body parts, sharing specific activities

6

Definition of a prokaryote

Unicellular organism, circular strand of free chromosomes
No membrane bound organelles

7

Definition of a eukaryote

Uni/multicellular, chromosomes in nucleus, normally have cytoplasmic, membranous organelles, DNA divided into many linear chromosomes, vary from cel to cell within organism
Includes complex organisms

8

Definition of a virus

Assemblage of DNA/RNA and proteins, parasitic of prokaryotes/eukaryotes
Invade cell, hijack protein synthesis to make more viruses
Only operate in host cells, no plasma membrane

9

What are living organisms made up of

Cells

10

What are higher organisms considered

Communities of vells

11

What can individual cells within communities do

Peform specialized functions

12

What is not considered a cell

Virus

13

Genetic structure of prokaryotes

Single, circular chromosome
In nuclei
No nucleus
No histones
Has plasmids

14

Genetic structure of eukaryotes

Paired chromosomes
Membrane bound nucleus
Has nucleolus
Has histones
Has extrachromosomal DNA in mitochondria and plasmids

15

Intracellular structures of prokaryotes

No mitotic spindle
No sterols
Internal membrane only in photosynthetic organisms
No ER
Respiration at cell membrane
No golgi
No lysososomes
No peroxisomes
70S ribosomes
No cytoskeleton

16

Intracellular structures of eukaryotes

Has mitotic spindle
Has sterols
Has membrane bound organelles
Has ER
Respiration at mitochondria
Has golgi
Has lysosomes
Has peroxisomes
80S ribosomes in cytoplasm, 70S in mitochondria
Has cytoskeleton

17

Extracellular structures of prokaryotes

Peptodoglycan, LPS, teichoic acid cell wall
Has capsule/slime layer
No cilia
Has pili and flagella

18

Extracellular structures of eukaryotes

Most don't have cell walls, chitin in fungi
Most don't have capsules or slime layers, pellicle/shell in some parasites
Cilia in some cell types
No pilli
Flagella in some cell types

19

Reproduction of prokaryotes

Binary fission
Asexual

20

Reproduction of eukaryotes

Mitosis/meiosis
Asexual/sexual

21

What is cell theory

All living things are made from cells
Arise through division of preexisting cells

22

Subcellular resolution and microscopes

Only EM can reveal subcellular details
TEM, see ultrastructure, electrons go through specimen
SEM, see cell surface, electrons scattered off cell surg=face by heavy metal coating of Au

23

Downfalls of EM

Elaborate prep needed
Only dead cells can be viewed

24

What limits the max size of a cell

Diffusion<50um = efficient
As cell size increases, V:SA decreases

25

How do specialized cells overcome the limitations of diffusion

Thin processes
Giant multinucleate cells
Gap junctions

26

Whats a thin process

Directed transport of substances around cell via, cytoskeleton (neurons, oligodendrocytes)

27

Giant multinucleate celles

Gene expression occurs in more than 1 place (skeletal muscle cells)

28

Gap juctions

Channels between cells, allow movement of substances between cells

29

Purpose of membrane bound cellular organelles

Allows specialized environments within
Different functions operate under different conditions (pH)
Single cell can have many functional compartments

30

Protein filaments that make up the cytoskeleton

Actin
-thinnest muscle fibres
Microtubules
-thickest, pull daughter cells apart
Intermediate filaments
-mechanical strength of cell