Cell Structure

Question 1

What are organelles?

Answer 1

Subcellular structures found within a cell.

Question 2

Explain the nucleus.

Answer 2

-Largest organelle
-Controls activities of the cell
-Contains chromosomes that carry genes which determine the proteins that the cell can make

Question 3

Explain the cell membrane.

Answer 3

-Boundary between the cytoplasm and the outside of the cell
-Selectively permeable (some chemicals can pass through and some can’t)

Question 4

Explain the cytoplasm.

Answer 4

-Jelly-like substance that contains the organelles
-Many chemical/metabolic reactions occur in it

Question 5

Explain the mitochondria.

Answer 5

-Carries out aerobic respiration
-Releases energy for the cell
-Cells with high demand for energy like muscle cells have many mitochondria

Question 6

Explain the cell wall.

Answer 6

-Found only in plant cells
-Made of cellulose
-Helps cell keep its shape
-Freely permeable so that any chemical can pass through it

Question 7

Explain the chloroplast.

Answer 7

-Found in some plant cells
-Contains chlorophyll, a green pigment
-Absorbs light for photosynthesis

Question 8

Explain the vacuole.

Answer 8

-Found in only plant cells
-Filled with cell sap, which contains mineral ions and dissolved sugars.
-Helps the cell keep its shape

Question 9

Explain the rough endoplasmic reticulum.

Answer 9

-Modification and transport of proteins

Question 10

Explain ribosomes.

Answer 10

-Synthesis of proteins

Question 11

Explain vesicles.

Answer 11

Membrane-bound bags containing fluids

Question 12

Name the 8 steps in the division of labour.

Answer 12

Atom => Molecule/compound => Organelle => Cell => Tissue => Organ => Organ system => Organism

Question 13

Explain cell division.

Answer 13

-Multicellular organisms start life as fertilised eggs called zygotes.
-It divides over and over through a process called mitosis/meiosis.

Question 14

What is differentiation?

Answer 14

-Cells in a developing embryo grow to carry out special functions.
-It is controlled by genes
-These genes can be switched on and off for the functions to work.

Question 15

What is the location, specialisation and function of a ciliated cell?

Answer 15

-Found in trachea and oviducts
-Specialised by cilia (tiny hairs that wave back and forth)
-To move mucus or an egg cell along the trachea or oviduct.

Question 16

What is the location, specialisation and function of a root hair cell?

Answer 16

-Found in plant roots
-Specialised by its protrusion that increases surface area
-To absorb water and minerals

Question 17

What is the location, specialisation and function of a red blood cell?

Answer 17

-Found in plasma
-Specialised by its flat disc shape, and large surface area, lack of nucleus and haemoglobin content
-To transport oxygen

Question 18

What is the location, specialisation and function of a sperm cell?

Answer 18

-Found in the male reproductive system
-Specialised by its tail and acrosome
-To fertilize an egg cell

Question 19

What is the location, specialisation and function of an egg cell?

Answer 19

-Found in the female reproductive system (ovaries)
-Specialised by its large size and energy-rich yolk in the cytoplasm to nourish the embryo before implantation

Question 20

What is the location, specialisation and function of a palisade cell?

Answer 20

-Found in plant leaves
-Specialised by the large amounts of chloroplasts and regular shape to pack many into a leaf
-To trap light for photosynthesis

Question 21

Explain the formulas to find magnification, image size and actual size.

Answer 21

Magnification= image/actual
Image= magnification x actual
Actual= image/magnification