Cell Structure and Function (week 2)

Question 1

why are cells so small?

Answer 1

cells are small to maximize surface area and create a high surface area to volume ratio

Question 2

Prokaryotic cells include:

Answer 2

bacteria

Question 3

eukaryotic cells include:

Answer 3

animal cells, tissue, plant

Question 4

Anton Van Leeuwenhoek

Answer 4

studies organisms in pond water; the first to study microorganisms

Question 5

1830 Schleiden and Schawaan

Answer 5

concluded that all living organisms are made of cells; formed the cell theory of biology

Question 6

cell theory of biology

Answer 6

1. all living organisms are made up of cells
2. cell is structural unit of life
3. cells arise by division
4. cells can be cultured to produce more cells

Question 7

what features do all cells have?

Answer 7

plasma membrane, cytoplasm, DNA, ribosomes, cytoskeleton

Question 8

what are the three types (domains) of cells?

Answer 8

Bacteria (prokaryote), archaea (prokaryote), eukarya (eukaryote)

Question 9

in vitro

Answer 9

outside organism or cell

Question 10

in vivo

Answer 10

inside organism or cell

Question 11

bacteria consists of:

Answer 11

mitochondria, chloroplasts, gram, negative/positive bacteria, capsules

Question 12

archaea consists of:

Answer 12

methanogens, hyperthermophiles, extreme halophiles

Question 13

eukarya consists of:

Answer 13

fungi, plants, animals, amoeba

Question 14

what is the size of bacteria? (earliest cell type)

Answer 14

5-10 um

Question 15

what does bacteria lack?

Answer 15

membrane bound organelles

Question 16

function of capsules (bac)

Answer 16

outer sticky protective layer

Question 17

function of cell wall (bac)

Answer 17

rigid structure; helps bacteria maintain its shape

Question 18

function of plasma membrane (bac)

Answer 18

separates cell from the environment

Question 19

function of nucleoid (bac)

Answer 19

where naked DNA is found

Question 20

function of cytoplasm (bac)

Answer 20

1. semi-fluid cell interior
2. no membrane bound organelles
3. metabolic enzymes and site of ribosome synthesis

Question 21

features of archaea

Answer 21

1. was thought to be bacteria
2. 5-10 um
3. lack membrane bound organelles
4. usually live in extreme environments (thermophiles, halophiles, methanogens)
5. eukaryote-like gene structures and ribosomes

Question 22

features of eukaryotes

Answer 22

contain membrane-bound organelles, include protists fungi, animals, plants, no capsule

Question 23

what structures occur in plant cells and not animal cells?

Answer 23

cell wall, central vacuole, and chloroplasts

Question 24

what structures occur in animal cells and not plant cells?

Answer 24

centrioles

Question 25

function of plasma membrane (euk)

Answer 25

lipids bilayer, channel proteins, hormone receptors, cholesterol

Question 26

function of cytoplasm (euk)

Answer 26

cytosol, organelles, cellular inclusions (everything inside cell, not outside of nucleus)

Question 27

function of nucleus (euk)

Answer 27

house of DNA

Question 28

function of nucleolus (euk)

Answer 28

site of rRNA (makes ribosomes)

Question 29

function of chromatin (euk)

Answer 29

DNA + protein

Question 30

function of pores (euk)

Answer 30

how mRNA gets out

Question 31

what is the endoplasmic reticulum? (euk)

Answer 31

highly folded network of membranes

Question 32

function of rough er

Answer 32

contains bound ribosomes, protein synthesis

Question 33

function of smooth er

Answer 33

little to no bound ribosomes, lipid synthesis, cellular detoxification, stores calcium ions

Question 34

function of Golgi apparatus (euk)

Answer 34

the ups plant to get proteins to where they need to be

Question 35

function of lysosomes

Answer 35

cell's recycling center (clean-up crew), digestive enzymes

Question 36

function of the endomembrane system

Answer 36

These organelles work together to modify, package, and transport lipids and proteins.

Question 37

what organelles are part of the endomembrane system?

Answer 37

1. Nuclear envelope 2. Rough and Smooth Endoplasmic Reticulum 3. Golgi Apparatus 4. Lysosomes 5.Vacuoles & Vesicles 6. Plasma Membrane

Question 38

what is the central dogma of molecular biology?

Answer 38

a theory stating that genetic information flows only in one direction, from DNA, to RNA, to protein, or RNA directly to protein.

Question 39

peroxisomes

Answer 39

hydrogen peroxide is very reactive and corrosive (often product of biological oxidation reactions)

Question 40

mitochondria

Answer 40

1. number of them in cells vary 2. they produce ATP 3. have their own small chromosome that directs its functions 4. make their own ribosomes

Question 41

mitochondrial DNA (mtDNA)

Answer 41

found in cell mitochondria and contains genetic material only from a mother (XX)

Question 42

nuclear DNA (nuDNA)

Answer 42

found in the nucleus of the cell and contains genetic material from both mother and father

Question 43

what is the endosymbiotic theory?

Answer 43

mitochondria and chloroplasts originated as endosymbiotic bacteria that lived inside the ancestors of eukaryotic cells

Question 44

what is some evidence of the endosymbiotic theory?

Answer 44

1. mitochondria and chloroplasts have their own DNA 2. they are surrounded by 2 or more membranes 3. both contain ribosomes that are like those found in bacteria 4. mitochondria have numerous enzymes and transport systems similar to those of bacteria, not eukaryotes

Question 45

what structures make up the mitochondria?

Answer 45

1. matrix (inside inner membrane) 2. cristae (extensions of the inner membrane) 3. intermembrane space (between inner and outer membrane) 4. double membrane

Question 46

what structures make up chloroplasts?

Answer 46

1. thylakoid space (lumen) 2. thylakoid 3. geranium (stack of thylakoids) 4. stroma (inside inner membrane but outside the thylakoids)

Question 47

function of chloroplasts

Answer 47

play a key role in photosynthesis

Question 48

function of thylakoids

Answer 48

membrane-bound flattened vesicles that absorb sunlight for photosynthesis

Question 49

function of stroma and inner/outer membranes

Answer 49

many of enzymes and & pigments necessary for photosynthesis are in membranes; some in stroma

Question 50

what are the three types of cytoskeletal filaments?

Answer 50

actin (microfilaments/double helix), intermediate (keratin; thicker cables), and microtubules (hollow tube, alpha and beta tubulin)

Question 51

function of actin filaments

Answer 51

1. maintain cell shape by resisting tension (pull) 2. move cells via muscle contraction or cell crawling 3. divide animal cells in two 4. move organelles and cytoplasm in plants, fungi, animals

Question 52

function of intermediate filaments

Answer 52

1. maintain cell shape by resisting tension (pull) 2. anchor nucleus and some other organelles

Question 53

function of microtubules

Answer 53

1. maintain cell shape by resisting tension (pull) 2. move cells via flagella or cilia 3. move chromosomes during cell division 4. assist formation of cell plate during cell division 5. move organelles 6. provide track for intracellular transport