Cells and Cell Transport

Question 1

What is typically in a prokaryotic cell?

Answer 1

murein cell wall
cell membrane
circular DNA
ribosomes
cytoplasm

Question 2

What will SOMETIMES be in a prokaryotic cell?

Answer 2

• capsid
• flagellum
• plasmid

Question 3

What are some differences between eukaryotic and prokaryotic cells?

Answer 3

• eukaryotic have nuclei
• 70s ribosomes in prokaryotic cell
• linear dna in eukaryotic
• prokaryotic organelles aren’t membrane bound

Question 4

what is binary fission?

Answer 4

How prokaryotic cells reproduce (asexually)
they divide into two daughter cells

they form two cells then four and keep doubling

Question 5

What is the nucleus?

Answer 5

contain generic material and DNA which determines the shape and function of the cell

it controls protein synthesis

Question 6

what is surrounding the nucleus?

Answer 6

The nuclear envelope and nuclear pores

Question 7

What are ribosomes

Answer 7

small organelles made of protein and rRNA

can be inside cytoplasm or on RER

Question 8

What is the function of ribosomes

Answer 8

used in protein synthesis joining amino acids together

Question 9

What is the rough endoplasmic reticulum?

Answer 9

Has ribosomes on its surface that produce secretory proteins
these proteins are then sent to Golgi for packaging

Question 10

What is the Smooth endoplasmic reticulum

Answer 10

doesnt have ribosomes
produces and transport lipids

Question 11

What are the Golgi apparatus/vesicles?

Answer 11

• apparatus adds carbohydrates to proteins received from the RER to form glycoproteins

• package proteins into vesicles for secretion

• produces lysosomes that release
lysozymes

Question 12

What are Lysosomes?

Answer 12

sacs containing hydrolytic enzymes

these need to be kept away from the rest of the cell as they will destroy it

Question 13

What are the functions of lysosomes?

Answer 13

Relese emzymes out the cell which digest material taken in by phagocytosis

Question 14

What is the function Mitochondria?

Answer 14

involved in aerobic respiration which produces ATP

Question 15

Describe the mitochondria

Answer 15

• bound by two membranes
• inter membrane space between outer and inner fold membrane
• cristae = folds of the inner membrane

Question 16

What is the the function of the matrix in a mitochondria

Answer 16

contains enzymes for respiration and ribosomes and DNA

Question 17

Which cells contain chloroplasts?

Answer 17

photosynthetic plant cells and algae

Question 18

What is the stroma

Answer 18

• surround chloroplasts and contain enzymes sugar and starch (its like the cytoplasm)

Question 19

What is the function of thylakoids

Answer 19

form stacks called grana
- they provide a large surface area for chlorophyll molecules to absorb light

Question 20

What is the function of the cell wall?

Answer 20

provides strength and support to the cell
- has cellulose and microfibrils

Question 21

What is the function of the vacuole?

Answer 21

contains soluble sugars salts and pigment

Question 22

What are tissues?

Answer 22

group of similar cells that perform a specific function
they have a common origin

Question 23

What is an organ?

Answer 23

a structure containing different tissues, which has a specific function

Question 24

What is a system?

Answer 24

contains two or more organs

Question 25

What is the function of epithelial cells in the small intestine?

Answer 25

absorption and digestion of products

Question 26

What is the function of microvilli

Answer 26

provides large surface area for absorption of digested food

Question 27

What is centrifugation?

Answer 27

It separates structures by density

Question 28

How are cells prepared for centrifugation?

Answer 28

They are broken up by homogenising in an ice-cold isotonic buffer solutions in a blender.

Question 29

What is the purpose of the solution being ice cold?

Answer 29

The low temperature prevents the action of enzymes that may cause self digestion

Question 30

Whats the purpose of the isotonic solution?

Answer 30

prevents osmotic movement of water in/out of organelles which may cause them to burst

Question 31

Why is a buffer solution used?

Answer 31

to maintain the pH so enzymes aren’t denatured

Question 32

Why is the homogenate filtered?

Answer 32

to remove cell debris that didn’t burst in homogenisation

Question 33

What happens during spins?

Answer 33

Homogenate spun at low speed and the densest organelle (nuclei) will form a pellet - solution remaining (supernatant) is then spun again at higher speed (repeated)

Question 34

What is the orders of organelles that will be obtained during centrifugation?

Answer 34

nucleus chloriplasts* cell wall* mitochondria endoplasmic reticulum ribosomes

Question 35

How does a light microscope work?

Answer 35

•light passed through a stained specemin

Question 36

How do electron microscope work?

Answer 36

use beam of electrons with a shorter wavelength than light thus providing a greater resolution

Question 37

How does a transmission electron microscope work?

Answer 37

• beam of electrons is TRANSMITTED through specemin - specimen should be thin and stained using heavy metal - they show internal structures

Question 38

How does a scanning electron microscope work?

Answer 38

• electron beam SCANNED across specimen - specimen coated with thin film of heavy metal - provide 3D image - lower resolution than TEM

Question 39

What js the equation for magnification

Answer 39

magnification = image size/ actual size

Question 40

What is in the cell membrane?

Answer 40

- phospholipid bilayer and protein

Question 41

Why is the cell membrane described as a fluid mosaic model?

Answer 41

- phospholipid molecules are constantly moving (fluid) - protein molecules unevenly distributed through membrane (mosaic)

Question 42

What can/cant easily pass through the phospholipid bilayer?

Answer 42

- lipid soluble molecules can pass quickly - water soluble ions and polar molecules cant pass thru easily and need channel:carrier proteins

Question 43

Whats the function of cholesterol?

Answer 43

provides strength to the membrane and restricts movement of phospholipids so its less fluid and less ions are lost

Question 44

What is the golgi made of

Answer 44

flattened membrane sacs

Question 45

Where are lysosomes formed

Answer 45

golgi

Question 46

What are microvilli

Answer 46

folds in a membrane