cells

Question 1

What is a nuclear envelope?

Answer 1

The nuclear envelope is a double membrane surrounding the nucleus

Question 2

What is the function of the holes in the nucleus and what is it called

Answer 2

Materials can move in and out of the nucleus via tiny holes in the nuclear envelope, called nuclear pores

remindier it brakes down during prophase of mitosis

Question 3

what and where are the ribosomes assembled

Answer 3

Within the nucleus, ribosomes are assembled by the nucleolus.

Question 4

what are vascles

Answer 4

Small fluid-filled sacs transport substances around inside a cell

Question 5

what are the small fluid-filled sacs transport substances around inside a cell

Answer 5

vascles

Question 6

What are ribosomes made up of?

Answer 6

Ribosomes are made up of RNA and proteins.

Question 7

What are the functions of the Golgi apparatus?

Answer 7

The Golgi stores and modifies proteins and lipids.

It then packages these substances into vesicles for transportation.

Some of the proteins packaged are enzymes. These enzymes are used to form lysosomes.

Question 8

What is a lysosome?

Answer 8

A lysosome is a membrane-bound organelle that releases digestive enzymes.

Question 9

What is the function of the mitochondria?

Answer 9

Mitochondria are the sites of aerobic respiration and production of ATP.

Question 10

What does the inner membrane in of the mitochondria form

Answer 10

Citrine

Question 11

What is the rough endoplasmic reticulum?

Answer 11

The rough endoplasmic reticulum (RER) is a system of folded membrainesthat has ribosomeson its outer surface.

The rough endoplasmic reticulum is where ribosomesare processed and packaged into vescles.

Question 12

How does the structure of the rough endoplasmic reticulum help enable the synthesis of proteins?

Answer 12

The rough endoplasmic reticulum has ribosomes and a large surface area.

Question 13

What is the smooth endoplasmic reticulum?

Answer 13

The smooth endoplasmic reticulum is a system of membranes with no ribosomes on the outer surface.

The smooth endoplasmic reticulum is where carbohydrates and lipids are secreted and packaged into vesicles.

Question 14

What is the function of the plant cell wall?

Answer 14

The plant cell wall provides rigidity to the cell.

The cell wall stops the cell from bursting as water enters it by osmosis, and this enables the cell to become turgid.

Question 15

What is the function of the vacuole in a plant cell?

Answer 15

The vacuole supports the plant by making cells turgid.

It also stores sugars and amino acids, which can act as a temporary food store.

Question 16

What are plant cell walls mainly composed of?

Answer 16

Plant and algal cell walls are mainly composed of the polymer cellulose.

Question 17

Fungal cell walls are mainly composed of which polymer

Answer 17

chitin

Question 18

What are thylakoids?

Answer 18

Thylakoids are flattened sacs in the chloroplast, containing the pigment chlorophyll.

Question 19

What are grana?

Answer 19

Grana are stacks of thylakoids found in the stroma of a chloroplast

Question 20

Starch and glycogen are coiled. Why does this make them good storage molecules?

Answer 20

It makes the molecules compact.

Question 21

What are prokaryotic cells?

Answer 21

Prokaryotic cells are single-celled organisms that lack membrane-bound organelles.

Question 22

In prokaryotic cells, the cell wall is made of….

Answer 22

murein

Question 23

A bacterium has a protective outer layer called a…

Answer 23

capsule

Question 24

a capsule protects a prokaryote from…

Answer 24

excessive water loss.

the host immune system.

Question 25

Some prokaryotic cells have small loops of DNA in their cytoplasm.
These are called…

Answer 25

plasmids

Question 26

Viruses also need a host cell in order to replicate.
As a result, we say that viruses are…

Answer 26

parasitic particles.

acellular.

Question 27

Some viruses have a protective outer envelope made of…

Answer 27

phospholipids

Question 28

Scanning electron microscopes provide …

Answer 28

a 3D image of the outer surface of a sample.

Question 29

transmission electron microscopes provide….

Answer 29

2D image of the sample’s internal structure.

Question 30

Historically, when using microscopes to look at cells, scientists struggled to distinguish cell organelles from other objects not part of the sample.

These objects are called

Answer 30

Artefacts

Question 31

Sequence the steps of cell fractionation:

Answer 31

Step 1: Homogenisation
The cells in the tissue sample are broken up.

Step 2: Filtration
Large cell debris and unbroken cells are removed.

Step 3: Ultracentrifugation
The cell organelles are separated.

Question 32

During the first step of cell fractionation, homogenisation, the tissue sample is placed in….

Answer 32

in an ice-cold, buffered and isotonic solution.

Question 33

Why is the solution buffered in the homologation phase of ultra centrifuging

Answer 33

To prevent enzymes and other proteins from denaturing

Question 34

Why is the solution isotonic in the homologation phase of ultra-centrifuging

Answer 34

To prevent osmosis, which could cause lysis (bursting)

Question 35

After the first two steps in cell fractionation, homogenisation and filtration, we end up with a filtered solution.

What does this solution contain?

Answer 35

Cell organelles

Question 36

what is formed ath the bottom of the tube within a centrifuge

Answer 36

a pellet

Question 37

within a centrifuge the remaining liquid in the tube is called the

Answer 37

supernatant.