Chapter 1

Question 1

Give six characteristics of cells

Answer 1

homeostasis, reproduce, growth/repair, use energy, adapt, have a boundary/highly organized

Question 2

What was Schleiden and Schwann’s contribution to the cell theory?

Answer 2

all organisms are made up of one or more cells, (( + the cell is the most basic unit of life))

Question 3

What was Virchow’s contribution to the cell theory?

Answer 3

/cells are the structural units of life/ ((all cells arise only from preexisting cells)

Question 4

What is the cell theory?

Answer 4

All cells arise from preexisting cells

Question 5

What is the central dogma of molecular biology?

Answer 5

DNA-(transcription)->RNA-(translation)->Protein

Question 6

Who invented the first microscope and what did he look at?

Answer 6

Hooke, looked at dead cells of cork

Question 7

What sort of things could the first microscope see? What was its magnification?

Answer 7

Cells, nuclei, plant cell vacuoles, chloroplasts?

30x

Question 8

Who invented the second microscope and what did he look at?

Answer 8

Van Leeuwenhoek, looked at live cells

Question 9

What sort of things could the second microscope see? What was its magnification?

Answer 9

Everything Hooke could see plus mitochondria and bacteria 100x

Question 10

Describe confocal microscopes

Answer 10

used to produce 3D images that are sharper than fluorescence microscopy

Question 11

Give the two main reasons why cells are small. Include examples.

Answer 11

Large surface area to volume ratio (nutrient uptake, waste disposal, diffusion) and maintaining sufficient concentration of reactants and catalysts

Question 12

Why can eukaryotic cells be larger than prokaryotic cells?

Answer 12

Their organelles allow them to concentrate molecules for reactions there

Question 13

Compare prokaryotes and eukaryotes: nucleus, size, organelles, location and type of DNA, uni or multi cellular

Answer 13

Eukaryotes have a nucleus, are larger, have organelles, have linear DNA in nucleus, and are mostly multicellular

Prokaryotes have no nucleus, are smaller, do not have organelles, have circular DNA in their cytosol, and almost all are unicellular

Question 14

Compare prokaryotes and eukaryotes: Shape, reproduction, ribosomes, speed of division, covering of DNA

Answer 14

Eukaryotes are variable in shape, reproduce slowly with mitosis, have 80s ribosomes, and have chromatin that packages their DNA

Prokaryotes are rod/sphere/corkscrew shaped, reproduce quickly with binary fission, have 70s ribosomes, and have “naked” DNA

Question 15

Describe the endosymbiotic theory. Include the reasons why it would happen.

Answer 15

An ancestral early eukaryote engulfed an aerobic bacteria, creating a mitochondria. A cell like that engulfed a photosynthetic bacteria (a cyanobacteria), creating chloroplasts.

The aerobic bacteria would have handled the oxygen, and the anaerobic bacteria would ingest food and protect the aerobic “symbiote”.

Question 16

What are the five main similarities between mitochondria, chloroplasts, and bacterial cells?

Answer 16

1 circular chromosome, binary fission replication, 70s ribosomes, small size, appearance on earth is anaerobic->photosynthetic->aerobic->eukaryotes

Question 17

Explain how the presence of certain membranes supports the endosymbiotic theory

Answer 17

the inner lipid bylayer of mitochondira and chloroplasts would be the bacteral cell’s, and the outer layer came from the cell that engulfed it

Question 18

Define cell

Answer 18

a small, membrane-enclosed unit filled with a concentrated aqueous solution of chemicals and endowed with the extraordinary ability to create copies of themselves by growing and then dividing in two

smallest living being, building blocks of life

Question 19

Define nucleus

Answer 19

a large, circular organelle enclosed by a nuclear envelope that contains DNA

Question 20

Define mitochondrion

Answer 20

worm-shaped branching organelles that generate energy (ATP) by cellular respiration in eukaryotic cells

Question 21

Define chloroplast

Answer 21

large, green organelles that are found only in the cells of plants and algae and carry out photosynthesis

Question 22

Define endoplasmic reticulum

Answer 22

an irregular maze of interconnected spaces enclosed by a membrane that makes most of the cell-membrane components and materials designed for export

Question 23

Define golgi apparatus

Answer 23

stacks of flattened, membrane-enclosed sacs that modify and package molecules made in the ER that are destined to be secreted from the cell or transported to another compartment

Question 24

`Define lysosome

Answer 24

small, irregularly shaped organelles in which intracellular digestion occurs, releasing nutrients from ingested food particles and breaking down molecules for recycling or excretion

Question 25

Define peroxisome

Answer 25

small, membrane enclosed vesicles that provide a safe environment for a variety of reactions in which hydrogen peroxide is used to inactivate toxic moleucles

Question 26

Define cytosol

Answer 26

a concentrated aqueous gel of large and small molecules; the part of the cytoplasm not contained in intracellular membranes

Question 27

Define each of the three types of cytoskeletal filaments: Actin filaments, microtubules, and intermediate filaments

Answer 27

Actin filaments aid in muscle contraction

Microtubules help move chromosomes

Intermediate filaments strengthen the cell

Question 28

What did Paul Nurse and colleagues discover?

Answer 28

certain cell division genes could be transferred between different species of yeast and even to humans

Question 29

Define protozoans

Answer 29

free-living, nonphotosynthetic, single-celled, motile eukaryotes with elaborate anatomy.

Question 30

What is the main advantage of multicellularity?

Answer 30

high specilization

Question 31

Give some evidence for a common ancestor cell

Answer 31

Similarities in DNA/metabolic pathways/amino acids/proteins and the characteristics of mitochondria and chloroplasts