Pre-reqs eukaryote notes

Question 1

A phospholipid bilayer that encloses the entire cell.

Answer 1

plasma membrane

Question 2

Defines the boundary of the cell; separates cell from the outside environment)
Regulates what can enter/exit the cell

Answer 2

plasma membrane

Question 3

composition of plasma membrane?

Answer 3

Carbohydrates (oligosaccharides) - on the outer surface of cell
Lipids
Phospholipids & glycolipids - form the membrane’s bilayer
Sterols - fit into the bilayer between the other lipids
Proteins - Dispersed throughout the bilayer

Question 4

Nucleus?

Answer 4

Function: (1) acts as the cell’s control center; (2) houses the DNA & the nucleolus.

Question 5

Double membrane layer
2 FUNCTIONS:
Surrounds nucleus, separates it from the rest of the cell.
Contains nuclear pores: protein-lined holes that regulate what enters and exits the nucleus

Answer 5

nuclear envelope

Question 6

Nucleolus?

Answer 6

Dark spot found inside the nucleus; associated with particular regions of the DNA.
Function: produces rRNA (to become part of the ribosome

Question 7

Function: carry out aerobic cellular respiration (break down glucose to make ATP).

Answer 7

mitochondria

Question 8

mitochondria structure?

Answer 8

Structure: surrounded by a double layer of membranes.
Cristae - folded inner membranes; where the electron transport chain is located
Matrix - inner space where the citric acid cycle (Krebs cycle) occurs

Question 9

chloroplasts?

Answer 9

Function: where photosynthesis occurs.
Contain Chlorophyll (the molecule that captures energy from light), which gives them the green color.

Question 10

structure of chloroplasts?

Answer 10

Structure: surrounded by a double layer of membranes.
Thykaloids - Stacks of membranes inside the chloroplast; where the light reactions of photosynthesis take place.
Stroma - space outside thylakoids where the dark reactions of photosynthesis (Calvin cycle) take place.

Question 11

Network of interconnected membranes extending throughout the cytosol.

Answer 11

endoplasmic reticulum

Question 12

ROUGH ER structure and function?

Answer 12

Continuous with nuclear envelope & covered with ribosomes.
Function: modifies proteins during translation.

Question 13

SMOOTH ER structure and function?

Answer 13

Not continuous with nuclear envelope; not covered with ribosomes; not involved in protein modification.
Function: synthesize lipids; detoxify & deactivate certain harmful substances.

Question 14

golgi complex structure and function?

Answer 14

stack of flat membrane-enclosed sacs that can resemble a stack of pancakes.
Functions:
Modify, process & package proteins, after translation is complete and they have left the ER.
Golgi modifications help direct proteins to their correct destinations.

Question 15

Lysosomes?

Answer 15

not found in plants

Function: digest food molecules and break down damaged components of the cell.

Question 16

lysosomes contain these?

Answer 16

hydrolases, which break down all sorts of different molecules by hydrolysis.

Question 17

peroxisomes?

Answer 17

Functions vary depending on cell type.
Animals - break down various compounds such as long-chain fatty acids by oxidation.
Plants - specialized peroxisomes play other roles.
Reactions inside generate harmful peroxides such as H202
A peroxisome enzyme called catalase converts H202 to water in order to protect the cell.

Question 18

Vacuoles in Animals, yeast:

Answer 18

temporary storage or transport outside the endomembrane system.

Question 19

Vacuoles in certain protists?

Answer 19

some vacuoles are formed during phagocytosis to hold the food particles; others are specialized to pump water out of the cell.

Question 20

Vacuoles in plants?

Answer 20

large central vacuole maintains turgor pressure; also plays roles in intracellular digestion & storage of nutrients or wastes

Question 21

what are these?

Answer 21

In eukaryotes, some are attached to the rER & others float in cytoplasm. Still others are located inside mitochondria and chloroplasts.

Question 22

cytoskeleton

Answer 22

A network of protein fibers extending throughout the cell.
3 different structural elements made of protein.
Microfilaments (smallest)
Microtubules (largest)
Intermediate filaments (mid-sized)

Question 23

functions of cytskeleton

Answer 23

Establish, maintain cell shape.
Movement of cell; Movement & positioning of organelles.
Roles in mitosis, meiosis and cytokinesis

Question 24

Outside the cell membrane, cells have structures used for cell-cell communication.
This is a fibrous network of proteins & polysaccharides produced by the cell and deposited outside the cell membrane.
It gives physical support to the cell.
Participates in regulating certain processes inside the cell.
Its crucial for many types of cell-cell communication.

Answer 24

extracellular matrix

Question 25

Bacterial cells, plant cells, fungus cells, some protist cells & some archaea cells have a CELL WALL. Rigid structure outside cell membrane that protects & supports the cell; helps maintain turgor pressure; prevents cells from collapsing due to osmotic pressure.

Answer 25

cell walls