Cell diversity

Question 1

Tissue

Answer 1

A group of similar cells that carry out the same function

Question 2

Organ

Answer 2

A group of tissues that work together to carry out a similar function

Question 3

Organ system

Answer 3

A group of organs that work together that work together to carry out a function

Question 4

Organism

Answer 4

A group of systems that work together

Question 5

Types of plant tissues

Answer 5

Dermal tissues
Vascular tissue

Question 6

Dermal tissue

Answer 6

A single layer of cells that surrounds the different part of a plant
* epidermis protects the plant

Question 7

Vascular tissue

Answer 7

Transports materials around the plant
Xylem
Phloem

Question 8

Xylem

Answer 8

Transports water and minerals around the plant

Question 9

Phloem

Answer 9

Transports food from the leaves to the other parts of the plants

Question 10

Animal tissues

Answer 10

Connective tissue
Nervous tissue
Epithelial tissue
Muscular tissue

Question 11

Connective tissue

Answer 11

Description: Consists of a number of cells spread out in a matrix (surrounding substance)
Function: joins and supports other body structures
Example: blood (red, white, platelets suspended in plasma)

Question 12

Nervous tissue

Answer 12

Description : nervous tissue is composed of nerve cells called neurons
Function: neurons are adapted to carry electrical impulses to and from the
brain and spinal cord

Question 13

Epithelial tissue

Answer 13

Description: sheets of flat cells that cover surfaces
Function: (googled): protection, filtration, absorption etc.
Example: pericardium surrounds the heart

Question 14

Muscular tissue

Answer 14

Description: long cells that can get longer or shorter (contract)
Function: (googled) movement
Example: walls of the heart

Question 15

Organ

Answer 15

Composed of a number of tissues that work together to carry out a similar function

Question 16

Plant organs

Answer 16

Stem
Leaf
Root
Flower
Seeds
Fruit

Question 17

Animal organs

Answer 17

Lungs
Heart
Stomach
Intestine
Skin
Liver

Question 18

Plant organ: The Leaf

Answer 18

The leaf is an organ that contains dermal tissue (protection) and vascular tissue (transport)
These tissues combine so the leaf can carry out the function of photosynthesis

Question 19

Animal organ: The Heart

Answer 19

The heart is an organ that contains four types of animal tissue
1. Connective tissue (blood, blood vessels (artery))
2. Epithelial tissue (pericardium)
3. Nervous tissue (heartbeat controlled by pacemaker)
4. Muscular tissue (walls of heart made of cardiac muscle)

Question 20

Systems

Answer 20

A system is a number of organs working together to carry out a similar function

Question 21

Animal systems

Answer 21

Digestive (stomach)
Circulatory (heart)
Nervous (brain)
Endocrine (produces hormones)
Urinary (kidney)

Question 22

Animal system: Digestive system

Answer 22

Consists of the mouth, oesophagus, stomach, small intestine, large intestine.

All of these combine to take in and break down food.

Question 23

Animal system: Circulatory

Answer 23

Consists of the heart, blood, blood vessels, lymph and lymph vessels

All of these work together to transport materials around the brain

Question 24

Tissue Culture

Answer 24

Tissue culture is the growth of cells in or on an artificial medium outside an organism

The tissue is removed from a plant or animal and grown in glassware or in a bioreactor under carefully controlled conditions

Growth is by mitosis and produces a cluster of identical offspring

Question 25

In vitro : meaning

Answer 25

Artificial environment

Question 26

Conditions needed for tissue growth

Answer 26

Oxygen Nutrients Growth hormones (rooting powder) Correct pH A suitable temperature Sterile conditions No bacteria present

Question 27

Application of tissue culture (use)

Answer 27

Micro-propagation (monoclonal antibodies) (cancer research) Skin graft (organs transplants) Biotechnology (insulin, cancer test)

Question 28

Micro-propagation cycle

Answer 28

Parent plant - ex plant - nutrient medium - callus - embryoid - embryo - plantlet

Question 29

Benefits of micro propagation

Answer 29

Large number of plants produced in a short time Plants grown this way are generally identical Can provide plants that are disease resistant Process is an inexpensive way to produce new plants

Question 30

Producing biotechnology products (micro-propagation)

Answer 30

Insulin Pregnancy tests Drug test kit Cancer testing kit (monoclonal antibodies)

Question 31

Cell continuity

Answer 31

The ability of cells to divide and survive from one generation to the next

Question 32

Why do cells divide?

Answer 32

Reproduction Growth and repair

Question 33

Chromosomes are…

Answer 33

Genetic material of the cell Found in the nucleus Composed of protein and dna coiled together

Question 34

Gene

Answer 34

A gene is a section of DNA that controls the production of a particular protein (that protein gives us the code for a particular trait)

Question 35

Haploid

Answer 35

(N) A haploid cell has a single set of chromosomes Eg: egg, sperm

Question 36

Diploid

Answer 36

2n A diploid cell has a double set of chromosomes

Question 37

Diploid number in humans

Answer 37

46

Question 38

Types of cell division

Answer 38

Mitosis (growth and repair) Meiosis (reproduction)

Question 39

Mitosis

Answer 39

A type of cell division that produces two identical daughter cells One nucleus divides to give two nuclei

Question 40

What do bacteria use mitosis for?

Answer 40

Reproduction

Question 41

The cell cycle

Answer 41

Interphase Prophase Metaphase Anaphase Telophase

Question 42

Interphase

Answer 42

Longest part of cells life 90% Chromosomes elongated - can’t distinguish individual chromosomes - chromatin Cell is growing

Question 43

Early part of interphase

Answer 43

Cell is active, producing new organelles (Mitochondria, chloroplast) and chemicals needed for growth (enzymes and other proteins)

Question 44

Later part of interphase

Answer 44

Chromosomes produce identical copies of themselves. The doubling produces chromosomes with two identical genes

Question 45

Cells not associated with reproductive system are called…

Answer 45

Somatic cells

Question 46

Homologous pair

Answer 46

Teo chromosomes of similar size with the same sequence of genes

Question 47

2 Metaphase

Answer 47

- The sister chromatids line up along the equator/middle of the cell - Each chromosome is connected to poles by a spindle fibre connected at the centromere.

Question 48

3. Anaphase

Answer 48

- The spindle fibres contract and pull the sister chromatids apart toward opposite poles - The strands are called chromosomes at this stage

Question 49

4. Telophase

Answer 49

- The chromosomes elongate and revert back to chromatin. - The spindle fibres break down - A nuclear membrane is formed around each group of four chromosomes. - The original nucleus has now divided into two identical nuclei

Question 50

Cell division that follows immediately after mitosis:

Answer 50

Cytokinesis

Question 51

Cell division: Animal cells

Answer 51

Cytokinesis occurs in animals by a process called cleavage furrow The cell membrane pinches inward forming a cleavage furrow which splits the cell in two

Question 52

Cell division: Plant cell

Answer 52

In plant cells vesicles gather in the area between the two nuclei to form a cell plate. The plate forms new cell walls which are separated by a middle lamella.

Question 53

Cancer

Answer 53

Cancer is the uncontrolled growth of cells due to damaged DNA

Question 54

Carcinogens:

Answer 54

Cancer causing agents such as cigarette smoke, radiation, uv rays, some viruses (HPV cervical cancer)

Question 55

Meiosis

Answer 55

A type of cell division that produces four daughter cells, each having half the number of chromosomes as the parent nucleus Used to produce sperm and egg cells