Cellular Biology

Front 1

Cell Theory

Back 1

1. All living things are composed of cells

2. The cell is the basic functional unit of life

3. The chemical reactions of life take place inside the cell

4. Cells arise only from pre existing cells

5. Cells carry genetic information in the form of DNA this genetic materil is passed from parent cell to daughter cell

Front 2

Six Kingdoms

Back 2

1. Bacteria

2. Archaea

3. Protista

4. Plantae

5. Animalia

Front 3

Cell Membrane funtion

Back 3

1. Encloses the cell and exhibits selective permeability

A. Permeable to small polar and non polar molecules

B. Small charged molecules pass through protein channels

C. Charged ions and larger charged molecules cross with assurance of carrier proteins

Front 4

Nucleus Function

Back 4

Controls activity of the cell including cell division. Contains DNA

Front 5

Ribosomes Function

Back 5

1. Sites of protein production

Front 6

Endoplasmic Reticulum Function

Back 6

1. Involved in the transport of materials throughout the cell.

A. Smooth ER does not contain ribosomes and not involved with protein synthesis but instead with metabolism and production of lipids

B. Rough ER contains ribosomes and plays a role in production of proteins

Front 7

Golgi Apparatus Function

Back 7

1. Receives vesicles with contents from smooth ER then modifies and repackages them into vesicles and distributes to cell surface by exocytosis

Front 8

Mitochondria Function

Back 8

1. Site of aerobic respiration within the cell and hence the suppliers of energy

Front 9

Centrioles

Back 9

1. Involved in spindle organization during cell division. Only found in animal cells! Made of microtubules!

Front 10

Lysosomes Function

Back 10

1. Membrane bound vesicles the contain hydrolytic enzymes involved in intracellular digestion.

2. Autolysis occurs when a cell commits suicide by rupturing the lysosomes

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Cytoskeleton Funtion

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1. Supports the cell, maintains its shape and aids in cell motility.

2. Composed of microtubules( rods of tubulin), microfilaments( rods of actin), intermediate filaments

Front 12

Simple Diffusion

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1. Passive process(requires no energy) dissolved particles move down their concentration gradient from high to low.

Front 13

Osmosis

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1. A simple diffusion of water from a region of lower solute concentration to a region of higher solute concentration

Front 14

Facilitated Diffusion

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1. Net movement of dissolved particles down their concentration gradient through special channels or carrier proteins (requires no energy)

Front 15

Active Transport

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1. The net movement of dissolved particles against their concentration gradients with help of transport proteins. Requires energy!

Front 16

Energy-independent carriers

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Facilitate the movement of compounds along a concentration gradient (Active Transport)

Front 17

Symporters

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Move two or more ions or molecules in the same direction across the membrane (Active Transport)

Front 18

Antiporters

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Exchange one or more ions or molecules for another ion or molecules across the membrane (Active Transport)

Front 19

Pumps

Back 19

Energy dependent carriers (requires ATP)

Front 20

Endocytosis

Back 20

Process in which the cell membrane invaginates forming a vesicle that contains extracellular medium allowing large volumes of extracellular material inside the cell.

Front 21

Pinocytosis

Back 21

The ingestion of fluids or small particles

Front 22

Phagocytosis

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The engulfing of large particles

Front 23

Exocytosis

Back 23

A vesicle within the cell fuses with the cell membrane and releases a large volume of contents to the outside

Front 24

Intracellular Circulatiin

Back 24

1. Brownian movement: kinetic energy spreads small suspended particles throughout the cytoplasm of the cell

2. Cyclosis or streaming: the circular motion of cytoplasm around the cell transports molecules

3. ER: forms a network of channels throughout the cytoplasm and provides a direct continuous passage way from the plasma membrane to the nuclear membrane

Front 25

Extracellular Circulation

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1. Diffusion

2. Circulatory system

Hint 25

2 examples

Front 26

Cell division definition

Back 26

Process by which a cell doubles its organelles and cytoplasm, replicates its DNA and the divides in two

1. Unicellular organisms: cell division is a means of reproduction

2. Multicellular organisms: it is a method of growth, development and replacement of worn-out cells

Front 27

Interphase

Back 27

A period of growth and chromosome replication. 90% of a cells life is spent in interphase. Chromosomes are not visible! DNA is uncoiled and called chromatin.

Front 28

Interphase consist of what 3 parts?

Back 28

1. G1: initiates interphase. Cell increases in size and synthesizes proteins. Length of G1 phase determines the length of entire cell cycle

2. S: DNA synthesis

3. G2: cell prepares to divide . It grows and synthesizes proteins

Front 29

Mitosis

Back 29

The division and distribution of the cells DNA to its two daughter cells such that each received a complete copy of the original genome. Takes place in somatic cells

Front 30

Karyokinesis

Back 30

Nuclear division

Front 31

Cytokineses

Back 31

Cell division

Near the end of telophase the cytoplasm divides into two daughter cells with a complete nucleus and its own set of organelles. In Animal cells a cleavage furrow forms. In plant cells a cell plate forms.

Front 32

Order of Mitosis

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1. Prophase

2. Metaphase

3. Anaphase

4. Telophase

5. Cytokinesis

Front 33

Prophase

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Chromosomes condense. Centriole pairs (only animals) separate and move toward opposite poles. Spindle apparatus forms. Nuclear membrane dissolves which allows for spindle fibers to interact with chromosomes

Front 34

Metaphase

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Centriole pairs are at opposite poles. Fibers of the spindle apparatus attach to each chromatid at the kinetochore( a protein located on the centromere). The spindle fibers align the chromosomes at the can't of the cell forming a metaphase plate.

Front 35

Anaphase

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Centromeres split so each chromatid has its own distinct centromere this allowing sister chromatids to separate by the shortening of the spindle fibers

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Telophase

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Spindle apparatus disappears. Nuclear membrane forms around each chromosome(diploid 2N) similar to it's parent cell. The chromosomes uncoil resuming their interphase form.

Front 37

Meiosis

Back 37

Process by which sex cells are produced which are haploid(1N). Involves 2 divisions of primary sex cells resulting in 4 haploid cells called gametes.

Front 38

Prophase I

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Chromatin condense to chromosomes. Spindle apparatus forms. The nucleoli and nuclear membrane disappear. Homologous chromosomes come together and intertwine in a process called synapses. Crossing over occurs and sister cromatids are no longer identical

Front 39

Tetrad

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Each synaptic pair of homogous chromosomes contains four chromatids (prophase I)

Front 40

Crossing over

Back 40

Sometimes chromatids of homogous chromosomes break at corresponding points and exchange equivalent pieces of DNA. These contact points are called chiasmata.

Front 41

Metaphase I

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Homologous pairs (tetrads) align at the equatorial plane and each pair attaches to a separate spindle fiber at kinetochore

Front 42

Anaphase I

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The homogous pairs separate and are pulled to opposite poles of the cell this process is called disjunction

Front 43

Disjunction

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In anaphase each chromosome of parental origin separates from is homologue of maternal origin and either chromosome can end up in either daughter cell

Front 44

Nondisjunction

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Occurs when cells do not separate appropriately during meiosis and results in daughter cells having an incorrect number of chromosomes

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Telophase I

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A nuclear membrane forms around each new nucleus. Each chromosome still consist of sister chromatid joined at a centromere

Front 46

Second meiotic division

Back 46

Similar to mitosis except that meiosis 2 is not proceeded by chromosomal replication. The new cells have haploid chromosomes