Variety Of Living Organisms & Structure

Question 1

What is the structure of the bacterial nucleus?

Answer 1

Bacteria lack a nucleus and instead have a circular chromosome of DNA.

Question 2

What makes up the cell walls of bacteria?

Answer 2

Bacterial cell walls are made of polysaccharides and proteins.

Question 3

What are small extra circles of DNA in bacteria called?

Answer 3

Small extra circles of DNA in bacteria are called plasmids.

Question 4

Can bacteria carry out photosynthesis, or how do they primarily obtain nutrients?

Answer 4

Some bacteria can carry out photosynthesis, but most feed off other living or dead organisms.

Question 5

What is a common characteristic of bacteria in terms of size and structure?

Answer 5

Bacteria are microscopic single-celled organisms.

Question 6

What role do bacteria play in ecosystems?

Answer 6

Bacteria are decomposers, breaking down organic matter.

Question 7

Provide examples of rod-shaped bacteria.

Answer 7

Examples include Escherichia Coli (E. Coli) commonly found in animal intestines and Lactobacillus Bulgaricus.

Question 8

Name a spherical bacterium and its role.

Answer 8

Pneumococcus is a spherical bacterium that acts as the pathogen causing pneumonia.

Question 9

What are protoctists, and why are they sometimes called the ‘dustbin kingdom’?

Answer 9

Protoctists are single-celled organisms, sometimes referred to as the ‘dustbin kingdom’ because they are a mixed group that doesn’t fit into plants, animals, or fungi.

Question 10

How do some protoctists, like Amoeba, resemble animal cells?

Answer 10

Some protoctists, such as Amoeba, have features similar to animal cells.

Question 11

Which protoctists have chloroplasts and share similarities with plants?

Answer 11

Some protoctists, like Chlorella, have chloroplasts and exhibit characteristics more akin to plants.

Question 12

Are all protoctists harmless, or do some act as pathogens?

Answer 12

Some protoctists, like Plasmodium, function as pathogens, causing diseases such as malaria.

Question 13

Are viruses living organisms?

Answer 13

Viruses are not living organisms; they are small particles.

Question 14

Which types of organisms can viruses infect?

Answer 14

Viruses are capable of infecting every type of living organism

Question 15

How do viruses reproduce, and where does this process occur?

Answer 15

Viruses can only reproduce inside living cells, taking over the host’s genetic machinery.

Question 16

Describe the cellular structure of viruses.

Answer 16

Viruses do not have a cellular structure

Question 17

What types of nucleic acid do viruses contain?

Answer 17

Viruses contain either DNA or RNA, but not both.

Question 18

Do viruses exhibit specific characteristics of living organisms, except for one?

Answer 18

Viruses do not carry out characteristics specific to living organisms except for reproduction.

Question 19

How do viruses reproduce, and what is the key step in this process?

Answer 19

Viruses reproduce by entering host cells, taking over the genetic machinery, and using it to produce more virus particles.

Question 20

Name examples of viruses and their associated effects.

Answer 20

Examples include Tobacco Mosaic Virus (discolors tobacco leaves), Influenza Virus (causes flu), and HIV (causes AIDS).

Question 21

What is the role of the nucleus in cells, and what is it composed of?

Answer 21

The nucleus determines cell behavior and contains chromosomes made of DNA.

Question 22

Describe the characteristics of the cytoplasm.

Answer 22

The cytoplasm is a jelly-like substance, primarily made of water and protein, where metabolic reactions occur.

Question 23

What is the function of the cell surface membrane, and what is it made of?

Answer 23

The cell surface membrane is a partially permeable membrane, that controls substance movement (in & out) ; it is made of lipids and proteins.

Question 24

Where does protein synthesis take place, and what are ribosomes made of?

Answer 24

Ribosomes are the sites of protein synthesis and are composed of RNA molecules and proteins.

Question 25

Where does aerobic respiration occur, and what are the structural components of mitochondria?

Answer 25

Mitochondria are the sites of aerobic respiration, containing outer and inner membranes and a gel-like material called the matrix.

Question 26

What is the role of the vacuole in plant cells, and how does it differ from animal cells?

Answer 26

The vacuole stores sugars, salts, and dissolved substances, maintaining turgor pressure, and is larger in plant cells compared to animal cells (little or no vacuole).

Question 27

Describe the composition and function of the cell wall in plant cells

Answer 27

The cell wall is a rigid layer made of cellulose, giving plants shape and preventing bursting.

Question 28

What do chloroplasts contain, and what is their role in plant cells?

Answer 28

Chloroplasts contain chlorophyll, a green pigment that traps sunlight for photosynthesis in plant cells.

Question 29

Name the characteristics shared by living organisms using the acronym MRSGREN.

Answer 29

Movement, Reproduction, Sensitivity, Growth, Respiration, Excretion, Require Nutrition.

Question 30

What are the characteristics of eukaryotic cells in terms of multicellularity, size, and organelles?

Answer 30

Eukaryotic cells can be both multicellular and unicellular, larger in size (10-100μm), and have membrane-bound organelles, including a nucleus. Examples: Animals, plants, fungi, protists.

Question 31

Describe the characteristics of prokaryotic cells regarding multicellularity, size, and organelles.

Answer 31

Prokaryotic cells are unicellular, smaller in size (1-10μm), lack membrane-bound organelles, and have no nucleus (free-floating DNA). Examples: Bacteria, archaea.

Question 32

What is the fundamental unit of life, and what is the source of all cells?

Answer 32

Cells are the basic structural unit of life, and all cells come from preexisting cells.

Question 33

What are organelles, and what makes them specialized?

Answer 33

Organelles are cell structures specialized with specific functions.

Question 34

What do cells collectively form, and what is the term for similar cells carrying out the same function?

Answer 34

Cells form tissues, and similar tissues carrying out the same function are grouped into organs.

Question 35

Define organs and how systems are formed.

Answer 35

Organs are made from tissues carrying out body functions, and systems consist of interdependent parts.