Unicellular and Multicellular

Question 1

Define Unicellular

Answer 1

an organism made up of a single cell

Question 2

Give some examples of unicellular organisms

Answer 2

Paramecium, most prokaryotes

Question 3

Define multicellular

Answer 3

Describes an organism consisting of more than one cell

Question 4

Give some examples of multicellular organisms

Answer 4

Animals, humans, insects, plants etc…

Question 5

What are protozoans?

Answer 5

group of heterotrophic unicellular eukaryotes belonging in the kingdom of Protista

Question 6

What are heterotrophs?

Answer 6

an organism that cannot synthesis its own organic compounds from single inorganic material and so rely on autotrophs (organic substances) to provide energy for them, usually by being consumed.
Eg. All animals, protozoan, fungi and most bacteria are heterotrophs, animals

Question 7

What is a colony of cells?

Answer 7

an organised association of unicellular organisms.

eg. volvox

Question 8

What are the 3 organising principles required for the evolution from unicellular organisms to multicellular?

Answer 8

The ability of cells to divide, specialise and communicate with other cells.

Question 9

MRS GREN

Answer 9

Movement

Reproduction

Sensitivity

Growth

Respiration

Excretion

Nutrition

Question 10

How does cell specialisation and differentiation occur?

Answer 10

the diversity of cell shape and structure reflects the evolutionary adaptions of cells to different environments

Question 11

What is cellular differentiation?

Answer 11

the process by which an unspecialised cell develops into a specialised cell

Question 12

What are 3 differences stem cells have that make them different from other cells in the body?

Answer 12

1st difference: they are unspecialised (have not yet specialised into a particular type of cell)

2nd difference: is that they have the potential to divide and replicate for long periods of time

3rd difference: relatively unspecialised cells can differentiate to form different specialised cells

Question 13

What are stem cells?

Answer 13

cells that specialised cells originate from

Question 14

What are the disadvantages of specialised cells?

Answer 14

The need for communication and co-ordination between cells, specialised cells are totally dependent on activities of other cells to perform tasks they can’t do.

Question 15

What are specialised cells important?

Answer 15

They increase efficiency and reduce duplication of effort

Question 16

What are the 4 basic types of tissue?

Answer 16

Connective tissue

Epithelial tissue

Nervous tissue

Muscle tissue

Question 17

What are connective tissue?

Answer 17

It provides support and holds various part of the body together.

Question 18

Give 4 examples of connective tissue.

Answer 18

Vertebrates

Cartilage

Bone

Blood

Question 19

What are epithelial tissue?

Answer 19

Covering that protects organs, lines body cavities and covers the surface of the body.

Question 20

How are epithelial tissues organised and how does it help them?

Answer 20

Organised into tightly packed single or layered sheets.

This increase their effectiveness as barriers that protects against mechanical injury, invasive micro organisms and loss of fluid.

Question 21

Give examples of what epithelial tissues line.

Answer 21

Lines internal and external surface such as blood vessels, digestive organs, kidney tubules, skin and airways.

Question 22

What are nervous tissue?

Answer 22

Means of communication between all body structures, and the cells in nervous tissue are highly specialised

Question 23

Give examples of nervous tissues.

Answer 23

Nerves, motor neuron, sensory neuron

Question 24

What are muscle tissue?

Answer 24

made of thin and very long thread-like cells called muscle fibres

Functions: posture and body support, locomotion and heat production

Question 25

What are the two systems that organs of plants are grouped in?

Answer 25

Shoot system

Root system

Question 26

What is the shoot system?

Answer 26

Comprised of all parts of the plant found above ground. Responsible for supporting the plant physically and the transportation of resources, as well as the absorption of oxygen and carbon dioxide, reproduction and carrying out photosynthesis in leaves

Question 27

What is the root system?

Answer 27

Below ground

Responsible for absorbing water and nutrients from the soil

Question 28

What are the 4 main types of plant tissues?

Answer 28

Meristematic tissue

Dermal tissue

Ground tissue

Vascular tissue

Question 29

What is meristematic tissue?

Answer 29

Composed of cells that undergo cell division by mitosis, the process by which plants grow.

Meristems are the only places in a plant where cell divide.
Found at the tips of roots and shoots, in a ring around the inside of stems and bracts

Question 30

What is dermal tissue?

Answer 30

Composed of the outermost cell layers of a plant

Epidermis
Protects plant from cuts, invasion by microorganisms and water loss

Question 31

What is ground tissue?

Answer 31

Composed of all the internal cells of a plant other than vascular tissue.
Consists of a variety of different cell types that are specialised for storage, support and photosynthesis

Eg. Fleshy portions of apples, pears,etc…

Question 32

What are the key roles of connective tissue?

Answer 32

Its key role is binding and supporting other tissues, and protects against damage, infection and heat loss

Question 33

What are the functions of epithelial tissue?

Answer 33

Functions of epithelial cells include secretion, selective absorption, protection, transcellular transport, and sensing.