Cell and Tissue Architecture

Question 1

Cell types are

Answer 1

Diverse

Question 2

Red Blood Cells

Answer 2

Biconcave to maximize surface area for gas exchange and ability to pass through veins

Question 3

Liver Cells

Answer 3

High amount of rough ER for protein synthesis

Question 4

Muscle Cells

Answer 4

Long, multinucleated specialized for contraction

Question 5

Neurons

Answer 5

Long slender extensions let neurons communicate

Question 6

Intestinal Cells

Answer 6

Microvilli increase absorptive surface area

Question 7

Tissue

Answer 7

Collection of cells that work together to perform a specific function

Question 8

Organ

Answer 8

Two or more tissues combine and function together

Question 9

Basal Lamina

Answer 9

Also known as the basement membrane, it is a thin, dense layer of extracellular matrix that lines most tissues forming the supporting structure and scaffolding for epithelial tissue and separates different types of cells, such as nerve cells and muscle cells.

Question 10

Epidermis

Answer 10

The top layer of the skin, made up of keratinocytes and melanocytes

Question 11

Dermis

Answer 11

The second layer of skin

Question 12

Cytoskeleton

Answer 12

Made up of Micortubules, microfilaments, and intermediate filaments. Cytoskeleton has a role in transport, maintaining shape and internal organization

Question 13

Microtubule

Answer 13

A hollow tube formed from tubulin dimers. Largest tube in diameter. Have a role in transport. Associated with the centrosome and cell division, as well as organelle arrangement. Consists of an alpha and beta subunit.

Question 14

Microfilament

Answer 14

A double helix of actin monomers, has a role in cell-cell attachment. Surrounds the circumference of the cell. Has a role in transport, muscle contraction, cell division, cytokinesis.

Question 15

Intermediate Filament

Answer 15

A strong fiber composed of IMF proteins, of which there are a diverse high number. Give cells stability and structure. Made of lamins in the nucleus and keratins in the cytoplasm.

Question 16

Microvilli

Answer 16

Increases cell surface area for absorption, has cross-linked actin-binding proteins

Question 17

Dynamic Instability

Answer 17

Polymerization and de polymerization. Growing and looking for something to latch onto, and moving back when not finding it. Plus end assembles quickly, minus end assembles slowly. Microtubules and microfilaments.

Question 18

Microtubule Transport

Answer 18

Kinesin carries cargo (vesicles) to the plus end, and Dynein to the minus end. This requires energy, ATP.

Question 19

Fish embryos

Answer 19

Melanin is dispersed outwards by kinesin, making the embryo dark in the dark. Granules are moved toward the center by dynein, causing the embryo to be light colored.

Question 20

H. V. Wilson

Answer 20

Broke sponges up into individual cells, then swirled back together and the cells were able to sort themselves out. This is due to cadherins, which are highly specific.

Question 21

Cadherins

Answer 21

Transmembrane proteins that provide cell-cell attachment

Question 22

Integrins

Answer 22

Transmembrane receptors that attach cells to proteins in the ECM.

Question 23

Tight Junction

Answer 23

Made up of occludin and claudin proteins, which hold cells together. Prevents stuff from getting between the cells. Is not structural.

Question 24

Adherens Junctions and Desmosomes

Answer 24

Involves intermediate filaments and cadherins. Cadherins between two cells will line up parallel with one another and hold the cells together, IMFs will attach to the parts of the cadherin within the cell. Cell-cell rigidity.

Question 25

Hemidesmosomes

Answer 25

Anchors the epithelial cells to the basal lamina by integrin. Also involved intermediate filaments.

Question 26

Gap Junctions and Plasmodesmata

Answer 26

Not structural, animals have gap junctions and plants have plasmodesmata. Allows molecules to pass between cells through small pores.

Question 27

Extracellular Matrix (Animal)

Answer 27

Underlying the basal lamina, made up of elastin fibers, collagen fibers, fibroblast nuclei. A gel-like matrix. Cells reside in a complex meshwork of ECM fibers.

Question 28

Extracellular Matrix (Plant)

Answer 28

“Secondary Cell Wall”, composed of cellulose (which is glucose molecules linked together) and lignin. Lignin provides support.

Question 29

Collagen

Answer 29

Triple helices that are bundled like steel cable wires and are the most abundant in the ECM.

Question 30

ECM and Cancer

Answer 30

Mesastatic cancer cells cross the capillary basal lamina twice, once to enter the circulatory system and again to leave it. Can cross the basal lamina through the use of specific kinds of integrins.

Question 31

ECM Necessity

Answer 31

When cells are grown three-dimensionally compared to two, or grown in ECM protiens, they look like actual cells.

Question 32

Joan Caron

Answer 32

There is more protein secretion (gene expression) of albumin when hepatocytes are in matrix proteins compared to just collagen, (especially laminin).