OTH3416 Unit 1 - The Cell questions n answers rated A+

OTH3416 Unit 1 - The Cell questions n
answers rated A+

Prokaryotes - ANS ✔✔- single-celled organisms that do not have a membrane-bound nucleus

- characterized by lack of nucleus

- fungi, protozoa, most algae

- cyanobacteria, bacteria, and rickettsiae



Eukaryotes - ANS ✔✔- multicellular organisms with membrane bound organelles

- cells of higher animals and plants

- more extensive intracellular anatomy and organization



Proks. vs. euks. - ANS ✔✔1. structural differences

2. chemical composition

3. biochemical activity

4. protein production / synthesis

5. mechanisms of transport across outer cellular membrane

6. enzyme content



nuclei (proks.) - ANS ✔✔carry genetic info in sngle ciruclar chromosome

- lack histone



histones - ANS ✔✔in euk. cells, binds DNA and are involved in supercoiling of DNA



Differentiation - ANS ✔✔(maturation) process of cell specialization

,- some cells perform one kind of function and other cells perform other functions



The eight chief cellular functions - ANS ✔✔1. movement

2. conductivity

3. metabolic absorption

4. secretion

5. excretion

6. respiration

7. reproduction

8. communication



[chief cellular functions] movement - ANS ✔✔muscle cells generate forces that produce motion



[chief cellular functions] conductivity - ANS ✔✔conduction as a response to stimulus
manifested by wave of excitation, an electrical potential that passes along surface of cell to
reach its other parts

- chief function of nerve cells



[chief cellular functions] metabolic absorption - ANS ✔✔all cells can take in and use nutrients
and other substances from surroundings



[chief cellular functions] secretion - ANS ✔✔some cells, like mucous gland cells, can synthesize
new substances from substances they absorb and then secrete new substances to serve, as
needed, elsewhere



[chief cellular functions] Excretion - ANS ✔✔all cells can rid themselves of waste products
resulting from metabolic breakdown of nutrients

,- lysosomes; contain enzymes that break down, or digest, large molecules, turning them into
waste products that are released from cell



[chief cellular functions] respiration - ANS ✔✔cells absorb oxygen, used to transform nutrients
into energy in the form of ATP

- mitochondria: location for cellular respiration, or oxidation



[chief cellular functions] reproduction - ANS ✔✔tissue growth occurs as cells enlarge and
reproduce themselves

- tissue maintenance requires that new cells be produced to replace cells that're normally lost
through cellular death

- not all cells capable of continuous division



[chief cellular functions] communication - ANS ✔✔vital for cells to survive as a society of cells

- allows for maintenance of dynamic steady state



plasma membrane - ANS ✔✔outer surface that regulates entrance and exit of molecules



cytoplasm - ANS ✔✔A jellylike fluid inside the cell in which the organelles are suspended



organelles - ANS ✔✔membrane-enclosed structures within eukaryotic cells



nucleus - ANS ✔✔- the largest membrane bound organelle

- contains...

1. nuclear envelope: pockmarked with nuclear pores

2. nuclear pores: allow chemical messages to exit/enter nucleus

3. nucleolus: small dense structure composed largely of RNA

, 4. most of cellular DNA

5. DNA binding-proteins (histones)

- primary functions: cell division, control of genetic information

- other functions: replication and repair of DNA and the transcription of the information stored
in DNA



chromatin - ANS ✔✔material made of DNA in association with histones



chromatid - ANS ✔✔



cytosol - ANS ✔✔



glycocalyx - ANS ✔✔



glycolipid - ANS ✔✔



glycoprotein - ANS ✔✔



spindle fiber - ANS ✔✔



proteostasis - ANS ✔✔state of cell balance of processes of protein synthesis, folding, and
dehydration

- depends on how quickly proteins are made, how long they survive, or when they are broken
down



proteolytic systems - ANS ✔✔1. lysosomes

2. ubiquitin-proteasome (UPS)