ultrastructure + function of organellses in cells

Question 1

What is the basic unit of life?

Answer 1

A cell

Cells are the fundamental building blocks of all living organisms.

Question 2

What are the two types of cells?

Answer 2

• Prokaryotic cells
• Eukaryotic cells

Prokaryotic cells are single-celled and lack a nucleus, while eukaryotic cells are complex and have a nucleus.

Question 3

Define prokaryotic cells.

Answer 3

Single-celled organisms that do not have a nucleus or membrane-bound organelles

Prokaryotic cells are simpler in structure than eukaryotic cells.

Question 4

Define eukaryotic cells.

Answer 4

Cells that make up multi-cellular organisms and contain a nucleus and membrane-bound organelles

Eukaryotic cells include those found in plants and animals.

Question 5

What is the approximate size range of eukaryotic cells?

Answer 5

10-100 um

Eukaryotic cells are generally larger than prokaryotic cells.

Question 6

What allows the ultrastructure of eukaryotic cells to be observed?

Answer 6

Electron microscope

Electron microscopes provide higher resolution images than light microscopes.

Question 7

What occurs in the cytoplasm of a cell?

Answer 7

Chemical reactions

The cytoplasm is the site where many cellular processes take place.

Question 8

What separates the cell cytoplasm from the external environment?

Answer 8

Cell surface membrane or plasma membrane

This membrane regulates the movement of substances in and out of the cell.

Question 9

What are organelles?

Answer 9

Different structures inside the cell cytoplasm

Organelles perform various functions necessary for cell survival.

Question 10

True or False: Eukaryotic organisms have genetic information as linear chromosomes.

Answer 10

True

Eukaryotic cells contain their genetic material organized into chromosomes within the nucleus.

Question 11

Fill in the blank: Eukaryotic organisms contain numerous _______.

Answer 11

specialised organelles

These organelles perform specific functions within the cell.

Question 12

What is the site of aerobic respiration in an animal cell?

Answer 12

Mitochondrion

Question 13

What regulates the transport of materials in and out of the cell?

Answer 13

Plasma membrane

Question 14

What structure takes part in cell division and forms spindle fibres?

Answer 14

Centrioles

Question 15

What contains genetic information and regulates metabolic cell activity?

Answer 15

Nucleus

Question 16

What modifies and packages newly made proteins into vesicles?

Answer 16

Golgi apparatus

Question 17

What transports materials around the cell or out of the cell?

Answer 17

Vesicle

Question 18

What is the dense spherical structure inside the nucleus that produces ribosomes?

Answer 18

Nucleolus

Question 19

What is the function of rough endoplasmic reticulum (ER)?

Answer 19

It synthesises and transports proteins.

Question 20

What is the role of cytoplasm in an animal cell?

Answer 20

Where metabolic reactions take place.

Question 21

What is responsible for protein synthesis when attached to the ER?

Answer 21

Ribosomes

Question 22

What synthesises carbohydrates and lipids in an animal cell?

Answer 22

Smooth endoplasmic reticulum (ER)

Question 23

What are lysosomes and what do they contain?

Answer 23

They are vesicles that contain hydrolytic enzymes.

Question 24

What is the structure of the plasma membrane?

Answer 24

Composed of a phospholipid bilayer, with proteins embedded in the layer.

Question 25

What is the function of the cytoplasm?

Answer 25

Maintains cell shape and stores chemicals needed for metabolic reactions.

Question 26

What surrounds the nucleus and has nuclear pores?

Answer 26

Nuclear envelope

Question 27

What does the nucleolus produce?

Answer 27

RNA and ribosomes.

Question 28

What is the structure of the rough endoplasmic reticulum?

Answer 28

Network of membrane bound flattened sacs called cisternae studded with ribosomes.

Question 29

What is the structure of the smooth endoplasmic reticulum?

Answer 29

Network of membrane bound flattened sacs called cisternae. No ribosomes.

Question 30

What does the Golgi apparatus do with newly made proteins?

Answer 30

Receives, modifies, and packages them into vesicles.

Question 31

What are vesicles?

Answer 31

Small spherical membrane bound sacs with fluid inside.

Question 32

What is the function of transport vesicles?

Answer 32

Transport materials inside the cell.

Question 33

What do secretory vesicles transport?

Answer 33

Proteins that are to be released from the cell to the cell surface membrane.

Question 34

What do lysosomes do?

Answer 34

Break down waste material including old organelles.

Question 35

Where does protein synthesis occur?

Answer 35

At the ribosomes.

Question 36

What are lysosomes?

Answer 36

Small spherical membrane bound sacs containing hydrolytic enzymes.

Question 37

What are ribosomes?

Answer 37

Tiny organelles attached to rough ER or free floating in the cell, consisting of two sub-units and not surrounded by a membrane.

Question 38

What are mitochondria?

Answer 38

Organelles with two membranes; the inner membrane is highly folded to form cristae.

Question 39

What is the function of mitochondria?

Answer 39

Site of the final stages of cellular respiration.

Question 40

What are centrioles?

Answer 40

Small tubes of protein fibres that form spindle fibres during cell division.

Question 41

What is exocytosis?

Answer 41

Process of vesicles fusing with plasma membrane and secreting contents.

Question 42

What is one key function of animal cells?

Answer 42

To synthesise proteins for use inside the cell, for cell multiplication, and for secretion out of the cell.

Question 43

Where are proteins synthesised in animal cells?

Answer 43

On ribosomes attached to rough endoplasmic reticulum.

Question 44

What happens to newly synthesised proteins in the rough ER?

Answer 44

They are transported through the cisternae and packaged into vesicles.

Question 45

What is the role of the Golgi apparatus?

Answer 45

To modify and package newly synthesised proteins into vesicles.

Question 46

What do secretory vesicles do?

Answer 46

Transport proteins to the cell surface membrane for release.

Question 47

What is the structure of a plant cell wall?

Answer 47

Made of cellulose forming a sieve-like network.

Question 48

What is the function of chloroplasts?

Answer 48

Site of photosynthesis, trapping light energy to produce carbohydrates.

Question 49

What is a vacuole?

Answer 49

A membrane-bound sac in the cytoplasm that contains cell sap.

Question 50

What is the function of the vacuole?

Answer 50

Maintains turgor to ensure a rigid framework in the cell.

Question 51

What is the tonoplast?

Answer 51

The partially permeable membrane of the vacuole.

Question 52

What is an amyloplast?

Answer 52

A double membrane-bound sac containing starch granules.

Question 53

What are plasmodesmata?

Answer 53

Microscopic channels which cross the cell walls of plant cells.

Question 54

What are pits in plant cells?

Answer 54

Pores in the cell walls of the xylem.