B1 Biology Cells and Tissues

Question 1

What are the 3 principles of cell theory?

Answer 1

• all living things are made up of one or more cells
• cells are the most basic unit of structure and function in all living things
• all cells are created by pre-existing cells

Question 2

What are the two different types of cells?

Answer 2

• eukaryotic cells
• prokaryotic cells

Question 3

What is the structure of a cell surface membrane?

Answer 3

phospholipid bilayer with proteins

Question 4

what is the function of a cell surface membrane?

Answer 4

It controls entry and exit of substances into and out of the cell

Question 5

what is the structure of a nucleus?

Answer 5

• nuclear envelope that is a double membrane that contains nuclear pores
• contains DNA

Question 6

what is the structure of a chromosome?

Answer 6

DNA wraps around histones to form chromatin which coils to form chromosomes

Question 7

what is the function of a nucleus?

Answer 7

to manage the cells genetic material and produce ribosomes in the nucleolus

Question 8

what is the structure of a mitochondrion?

Answer 8

• double membrane
• inner membrane is folded to form cristae
• fluid interior is the matrix

Question 9

what is the function of a mitochondrion?

Answer 9

the site of cellular respiration

Question 10

what is the structure of a ribosome?

Answer 10

constructed of RNA molecules

Question 11

what is the function of a ribosome?

Answer 11

the site of protein synthesis

Question 12

what is the structure of a rough endoplasmic reticulum?

Answer 12

a network of membranes of flattened sacs called cisternae, ribosomes are bound to the surface

Question 13

what is the function of a rough endoplasmic reticulum?

Answer 13

responsible for the synthesis and transport of proteins

Question 14

what is the structure of a smooth endoplasmic reticulum?

Answer 14

a network of membranes of flattened sacs called cisternae, does not contain any ribosomes

Question 15

what is the function of a smooth endoplasmic reticulum?

Answer 15

it is responsible for lipid and carbohydrates synthesis and storage

Question 16

what is the structure of a golgi apparatus?

Answer 16

a compact structure formed of cisternae, does not contain any ribosomes

Question 17

what is the function of a golgi apparatus?

Answer 17

modifying proteins and ‘packaging’ then into vesicles

Question 18

What are the types of golgi vesicles?

Answer 18

• lysosomes (which stay in the golgi apparatus)
• secretory vesicles

Question 19

what is the function of a secretory vesicle?

Answer 19

to carry their contents to the plasma membrane where they can be released to the outside of the cell

Question 20

what is the structure of a centriole?

Answer 20

made of tubulin

Question 21

what is the function of a centriole?

Answer 21

• formation of the spindle in mitosis
• formation of cilia and flagella

Question 22

what is the function of a cytoskeleton?

Answer 22

controls cell movement and the movement of organelles within cells and helps to hold organelles in place

Question 23

what is the structure of a lysosome?

Answer 23

a collection of enzymes surrounded by a single-layer membrane

Question 24

what is the function of a lysosome?

Answer 24

use their digestive enzymes to break down worn out cell components

Question 25

what is the structure of a chloroplast?

Answer 25

- a double membrane structure with - internal fluid called stroma - internal network of membranes containing flattened sacs called thylakoids - lots of thylakoids stacked together are called granum - granum (plural grana) contains the chlorophyll pigments - contain DNA and ribosomes

Question 26

what is the function of a chloroplast?

Answer 26

responsible for photosynthesis in plant cells - able to make their own proteins

Question 27

what is the structure of a cell wall?

Answer 27

made of cellulose, are permeable (substances can pass in and out), rigid.

Question 28

what is the function of a cell wall?

Answer 28

gives the plant cell shape and acts as a defence mechanism by protecting the contents of the cell.

Question 29

what is the structure of a cell vacuole?

Answer 29

membrane lined sacs in the cytoplasm containing cell sap, membrane is called tonoplast which is selectively permeable

Question 30

what is the function of a vacuole?

Answer 30

to make sure all the contents of the cell push against the cell wall and maintain a rigid framework to ensure turgor pressure

Question 31

what is the difference in overall cell shape between plant and animal cells?

Answer 31

- plant cells have a cell wall and cell-surface membranes which gives them their rectangular cell shape - animal cells only have a cell surface-membrane and no cell wall

Question 32

what organelles do plant cells and animal cells both have?

Answer 32

- Ribosome - Mitochondria - Cell-surface membrane - Cytoplasm - Smooth endoplasmic reticulum - Rough endoplasmic reticulum - Nucleus - Golgi apparatus

Question 33

what organelles do plant cells and animal cells not have in common?

Answer 33

animal cells: ribosomes plant cells: chloroplasts, cell wall, cell vacuole

Question 34

How do eukaryotic cells become specialised?

Answer 34

- specialisation occurs through differentiation from stem cells

Question 35

why do eukaryotic cells become specialised?

Answer 35

to perform particular functions

Question 36

what is different about a prokaryotes cytoplasm compared to a eukaryotes cytoplasm?

Answer 36

they have cytoplasm that lacks membrane-bound organelles

Question 37

what is different about prokaryotic cells ribosomes?

Answer 37

they have smaller ribosomes

Question 38

what is different about a prokaryote's nucleus?

Answer 38

they have no nucleus, just a single circular DNA molecules that is free in the cytoplasm

Question 39

what does prokaryotic cells cell wall contain?

Answer 39

murein/peptidoglycan (a glycoprotein)

Question 40

do prokaryotic cells have plasmids?

Answer 40

yes, they may have one or more plasmids

Question 41

do prokaryotic cells have a capsule surrounding the cell?

Answer 41

they may have a capsule surrounding the cell

Question 42

do prokaryotes have flagella?

Answer 42

they may have one or more simple flagella