What are Cells? - Chapter 2

All organisms function according to the cell theory.

What does the cell theory state?

Answer explanation

The cell theory states that:

- All living things are made up of cells

- Cells are the smallest and most basic units of life

-All cells come from pre-existing cells.

Explain the difference between Prokaryotic Cells and Eukaryotic Cells

Answer explanation

Eukaryotic cells contain many membrane-bound organelles, multiple linear chromosomes of DNA packed in a nucleus, and tend to be larger than prokaryotes.

- Cell replication occurs through Mitosis or Meiosis

Prokaryotic cells lack a nucleus, have a single loop of circular DNA, and may contain some smaller circular units of DNA called plasmids.

- Cell Replication occurs through Binary Fission

Cells are made up of many different structures that work together to increase the efficiency of the cell. 

These compartments are known as __________, and all have different structures that help them perform their function.

Every cell is surrounded by a ___________________ which controls what can and cannot enter the cell. 

Inside each cell is a fluid substance known as the ____________, which contains the dissolved salts, nutrients, and molecules necessary for cell function. 

All the organelles (except the nucleus) and the cytosol in which they float make up the __________.

Answer explanation

Cells are made up of many different structures that work together to increase the efficiency of the cell. 

These compartments are known as organelles, and all have different structures that help them perform their function.

Every cell is surrounded by a plasma membrane which controls what can and cannot enter the cell. 

Inside each cell is a fluid substance known as the cytosol, which contains the dissolved salts, nutrients, and molecules necessary for cell function. 

All the organelles (except the nucleus) and the cytosol in which they float make up the cytoplasm.

You have one minute to identify as many organelles as you can

Answer explanation

Nucleus

Ribosomes

Rough endoplasmic reticulum

Smooth endoplasmic reticulum

Golgi apparatus

Lysosomes

Mitochondria

Chloroplasts

Vacuole

Plasma membrane

Cell wall

Vesicle

Cytoskeleton

Cytosol

Identify this structure and explain the function of this organelle.

Answer explanation

The nucleus is surrounded by a double membrane. Its role is to protectand confine the genetic information (DNA) of the cell. Inside thenucleus is a smaller structure known as the nucleolus which is the site ofribosome production.

Identify the two organlles shown in this picture and explain the role of both.

Answer explanation

Rough ER

A membranous chain of connected and flattened sacs which are

coated with ribosomes. This allows the rough endoplasmic reticulum

to synthesise and modify proteins. The rough endoplasmic reticulum

typically surrounds, or is close to, the nucleus.

Smooth ER

A membranous chain of connected and flattened sacs which are

not coated with ribosomes. The smooth endoplasmic reticulum is

responsible for the production of lipids in a cell.

Identify the Organelle and explain the role of this organelle.

Answer explanation

An organelle with a highly folded inner membrane surrounded by a

second outer membrane. Mitochondria are the site of aerobic cellular

respiration, a chemical reaction that produces the ATP required to power

cellular processes. They also contain their own DNA and ribosomes.

Identify the Organelle and explain the role of this organelle.

Answer explanation

A double membrane-bound organelle that contains flattened, fluid-filled

sacs that are the site of photosynthesis. Chloroplasts also contain their own DNA and ribosomes.

Explain the main differences between plant and animal cells.

Answer explanation

A cell wall made of cellulose is present in plant cells but not animal cells.

Chloroplasts are present in plant cells but not animal cells.

Vacuoles in animal cells are small and there can be many or none, whereas plant cells tend to have

one large vacuole.

What is meant by Surface Area to Volume ratio and identify if we want this ratio to be high or low

Answer explanation

Surface Area : Volume ratio

(SA:V) is a comparison of the

amount of surface area per unit of volume. In Biology, SA:V influences temperature regulation, and a high SA:V leads to more effective

transport into and out of cells.