topic 2 - eukaryotic cells and organelles

Question 1

what are eukaryotic organisms

Answer 1

complex cells that contain a nucleus and organelles enclosed by a plasma membrane

Question 2

four examples of eukaryotic cells

Answer 2

animal cells, plant cells, all cells in algae and fungi

Question 3

name 11 organelles contained in an animal cell

Answer 3

(1) plasma (cell surface) membrane
(2) rough endoplasmic reticulum
(3) smooth endoplasmic reticulum
(4) nucleus
(5) nucleolus
(6) nuclear envelope
(7) lysosome
(8) ribosome
(9) cytoplasm
(10) mitochonrion
(11) golgi apparatus

Question 4

do plant cells have the same organelles as animal cells

Answer 4

plant cells have all the same organelles as animal cells but a few added extra

Question 5

name 14 organelles contained in a plant cell

Answer 5

(1) plasma (cell surface) membrane
(2) rough endoplasmic reticulum
(3) smooth endoplasmic reticulum
(4) nucleus
(5) nucleolus
(6) nuclear envelope
(7) lysosome
(8) ribosome
(9) cytoplasm
(10) mitochonrion
(11) golgi apparatus
(12) cellulose cell wall
(13) vacuole
(14) chloroplast

Question 6

how are algae a lot like plant cells

Answer 6

they have all the same organelles including a cell wall and chloroplast

Question 7

what are the two key differences that differenciates fungal cells from plant cells

Answer 7

(1) their cell walls are made of chitin, not cellulose
(2) they don’t have chloroplasts (as they don’t photosynthesise)

Question 8

what are organelles

Answer 8

subcellular structures that exist within most cell types that has a very specific function or job

Question 9

describe the cell surface (plasma) membrane

Answer 9

the membrane found on the surface of animal cells and just inside the cell wall of other cells - it’s made mainly of lipids and proteins

Question 10

what is the function of a cell surface (plasma) membrane

Answer 10

regulates the movement of substances into and out of the cell - it also has receptor molecules on it which allows it to respond to chemicals like hormones

Question 11

describe the nucleus

Answer 11

a large organelle surrounded by a nuclear envelope (double membrane) which contains many pores - the nucleus contains chromosomes (which are made from protein bound linear DNA) and one or more structures called nucleolus

Question 12

what are the functions of a nucleus

Answer 12

controls the cell’s activities (by controlling the transcription of DNA) - DNA contains instructions to make proteins - the pores allow substances to move between the nucleus and the cytoplasm - the nucleolus makes ribosomes

Question 13

describe the mitochondrion

Answer 13

they’re usually oval shaped - they have a double membrane - the inner one is folded to form structures called cristae - inside is the matrix which contains enzymes involved in respiration

Question 14

what is the function if mitochondrion

Answer 14

the site of aerobic respiration, where ATP is produced - they’re found in large numbers in cells that are very active and require a lot of energy

Question 15

describe a chloroplast

Answer 15

a small, flattened structure found in plant and algal cells - it’s surrounded by a double membrane, and also has membranes inside called thylakoid membranes - these membranes are stacked up in some parts of the chloroplast to form grana - grana are linked together by lamellae - thin, flat pieces of thylakoid membrane

Question 16

what are the functions of a chloroplast

Answer 16

the site where photosynthesis takes place - some parts of photosynthesis happen in the grana, and other parts happen in the stroma (a thick fluid found in chloroplasts)

Question 17

describe the golgi apparatus

Answer 17

a group of fluid filled, membrane bound flattened sacs - vesicles are often seen at the edges of the sacs

Question 18

what are the functions of the golgi apparatus

Answer 18

it processes and packages new lipids and proteins- it also makes lysosomes

Question 19

describe the golgi vesicles

Answer 19

a small fluid filled sac in the cytoplasm, surrounded by a membrane and produced by the golgi apparatus

Question 20

what are the functions of the golgi vesicle

Answer 20

it stores lipids and proteins made by the golgi apparatus and transports them out of the cell (via the cell surface membrane)

Question 21

describe a lysosome

Answer 21

a round organelle surrounded by a membrane with no clear internal structure- it’s a type of golgi vesicles

Question 22

what’s the functions of a lysosome

Answer 22

contains digestive enzymes called lysozymes - these are kept separate from the cytoplasm by the surrounding membrane and can be used to digest invading cells or to break down worn out components of the cell

Question 23

describe a ribosome

Answer 23

a very small organelle that either floats free in the cytoplasm or is attached to the rough endoplasmic reticulum - it’s made up of proteins and RNA - it’s not surrounded by a membrane

Question 24

what is the function of a ribosome

Answer 24

the site where proteins are made

Question 25

describe a rough endoplasmic reticulum (RER)

Answer 25

a system of membranes enclosing a fluid filled space - the surface is covered with ribosomes

Question 26

what is the function of the rough endoplasmic reticulum (RER)

Answer 26

folds and processes proteins that have been made at the ribosomes

Question 27

describe a smooth endoplasmic reticulum (SER)

Answer 27

simulate to rough endoplasmic reticulum, but with no ribosome

Question 28

what is the function of a smooth endoplasmic reticulum (SER)

Answer 28

it synthesises and processes lipids and carbohydrates

Question 29

describe a cell wall

Answer 29

a rigid structure that surrounds cells in plants, algae and fungi - in plants and algae it’s made mainly of the carbohydrate cellulose - in fungi it’s made of chitin

Question 30

what are the functions of a cell wall

Answer 30

it supports cells and prevents them from changing shape

Question 31

describe a cell vacuole

Answer 31

a membrane bound organelle found in the cytoplasm of plant cells - it contains cell sap - a weak solution of sugar and salts - the surrounding membrane is called the tonoplast

Question 32

what are the functions of a cell vacuole

Answer 32

helps to maintain pressure inside the cell and keep the cell rigid - this stops plants wilting - also involved in the isolation of unwanted chemicals inside the cell

Question 33

what is a specialised cell

Answer 33

cells with unique structures and functions in the body

Question 34

what are 3 ways epithelial cells in the small intestine specialised to absorb food efficiently

Answer 34

(1) the walls of the small intestine have lots of finger like projections called villi - these increase surface area for absorption

(2) epithelial cells on the surface of the villi have folds in their cell surface membranes called microvilli - microvilli increase surface area even more

(3) they also have lots of mitochondria - to provide energy for the transport of digested food molecules into the cell

Question 35

how are specialised cells organised

Answer 35

into tissues, organs and organ system

Question 36

what are specialised cells grouped together to form in multicellular eukaryotic organisms

Answer 36

tissues

Question 37

what is a tissue

Answer 37

a group of cells working together to perform a particular function

Question 38

how what do epithelial cells make up

Answer 38

epithelial tissues

Question 39

what three tissues work together to form the stomach

Answer 39

epithelial tissue, muscular tissue, grandular tissue

Question 40

what is the digestive system

Answer 40

an organ system made up of all the organs involved in the digestion of food including the small intestine, large intestine and liver