cell organisation and structure

Question 1

what is the structure of SER?

smooth endoplasmic reticulum

Answer 1

a membrane-bound organelle within the cytoplasm of eukaryotic cells and has a tube-like structure

Question 2

what is the function of the SER?

smooth endoplasmic reticulum

Answer 2

is to synthesis and store lipids and carbohydrates

Question 3

what is the structure of the RER?

rough endoplasmic reticulum

Answer 3

membrane-bound organelle, a series of flattened sacs and has ribosomes attached to it

Question 4

what is the function of the RER?

rough endoplasmic reticulum?

Answer 4

is responsible for the synthesis and transport of proteins

Question 5

what is the structure of ribosomes?

Answer 5

• non-membrane-bound organelle, floats freely in the cytoplasm and is attached to the RER
• eukaryotes ribosomes have 70s ribosomes in the matrix of the mitochondria
• 80s ribosomes are attached to the RER

Question 6

what is the function of ribosomes?

Answer 6

is the site of protein synthesis. role of bringing amino acids together to form proteins

Question 7

what is the structure of the nucleus?

Answer 7

found in only eukaryotic cells.

• surrounded by its own membrane, nuclear envelope. pores in the nuclear envelope allow for the passage of molecules in and out of the cell.
• contains DNA of the cell and is the site for DNA replication

Question 8

what is the function of the nucleus?

Answer 8

controls the growth and reproduction of the cell

Question 9

what is the function of the nucleolus?

Answer 9

the nucleus contains a small dark structure called the nucleolus which synthesises ribosomes. the DNA in a nucleus exists a chromatin

Question 10

what is the structure of chloroplasts?

Answer 10

• membrane-bound organelle, has a small flattened structure.
• has a double membrane and the inner one is called the thylakoid membrane.
• the watery stroma contains stacks of folded membranes or thylakoids to form grana

Question 11

what is the function of chloroplasts?

Answer 11

found only in plant cells and is where photosynthesis takes place

Question 12

what is a eukaryotic cell?

Answer 12

contain membrane-bound organelles, including a nucleus. eukaryotes can be single-celled or multi-celled. e.g animal and plant cells

Question 13

what are prokaryotic cells?

Answer 13

do not contain a nucleus or any other membrane-bound organelle. E.g bacteria cell

Question 14

what are the cell features of eukaryotic cells?

Answer 14

• cell/plasma membrane
• cytoplasm
• DNA in a nucleus surrounded by the nuclear envelope
• 70s and 80s type ribosomes
• mitochondria (plant)
• chloroplasts (plant)

Question 15

what are the cell features of prokaryotic cells?

Answer 15

• cell/plasma membrane
• cytoplasm
• DNA in a loop
• 70s type ribosomes
• mesosomes

Question 16

what are the differences between prokaryotic and eukaryotic cells?

Answer 16

• euk have a membrane-bound nucleus, prok doesn’t
• prok have endoplasmic reticulum
• euk have Golgi body

Question 17

what is the structure of the mitochondria?

Answer 17

is a membrane-bound organelle. it has a double membrane, the outer one is smooth but the inner membrane is folded to form a structure called cristae, surrounding the watery matrix

Question 18

what is the function of the mitochondria?

Answer 18

is the site of aerobic respiration, which produces energy and ATP in cells

Question 19

what is the structure of the Golgi apparatus?

Answer 19

• euk cells only
• membrane-bound organelle and is composed of flattened sacs. vesicles are seen at the edge of the sacs
• vesicles may be secretory vesicles that store and transport materials within the cell. can be transported to other organelles

Question 20

what is the function of the Golgi apparatus?

Answer 20

is responsible for transporting, modifying, and packaging proteins and lipids into vesicles

Question 21

what is the structure of a lysosome?

Answer 21

a single membrane-bound organelle. is a spherical shape and floats freely within the cell, outside the nucleus

Question 22

what is the function of a lysosome?

Answer 22

is a type of Golgi apparatus. they release digestive enzymes to break down pathogens. to destroy the cells and unwanted organelles

Question 23

structure and function of the cell wall?

Answer 23

made from polysaccharide cellulose. the cellulose fibers form cross-links which give the wall strength
function - holds the cell together and gives shape and support to plant cells

Question 24

what is the structure of the plasma membrane?

Answer 24

• has a phospholipid bilayer that is permeable to small, non-polar molecules. however, it is permeable to larger ones and ions.
• has receptors to allow cell recognition and molecules to be recognised
• ion channels linked to the receptor allow rapid diffusion of specific ions to pass through

Question 25

what is the function of carrier proteins in the membrane?

Answer 25

the role of carrier proteins is to bind to large polar molecules such as sugars and amino acids and transport them across the membrane

Question 26

what is the function of the plasma membrane?

Answer 26

acts as a barrier between cell content and the surrounding protect the cell from its surroundings

Question 27

what is the structure of the cytoplasm?

Answer 27

consists of a liquid called cytosol and it is a watery matrix forming the bulk of the cell

Question 28

what is the function of the cytoplasm?

Answer 28

is where all the organelles are suspended and are where chemical reactions take place.