Key Area 1: Producing New Cells

Question 1

Mitosis

Answer 1

Provides new cells for growth, repair of damaged tissues and replacement of dead or damaged cells. It also maintains the diploid chromosome complement.

Question 2

Diploid cells have?

Answer 2

Two matching (paired) sets of chromosomes, which are replicated during mitosis.

Question 3

Chromosome

Answer 3

a thread-like structure in the nucleus of a cell that contains DNA and carries genetic information

Question 4

Chromatid

Answer 4

one of two identical halves of a duplicated chromosome

Question 5

Spindle fibres are?

Answer 5

protein structures that help divide genetic material in a cell during cell division

Question 6

Equator

Answer 6

the plane where the chromosomes align during metaphase

Question 7

Diploid chromosome

Answer 7

a chromosome in a cell that contains two sets of chromosomes, one from each parent

Question 8

Complement

Answer 8

the complete set of chromosomes for a species

Question 9

Unspecialised cells

Answer 9

a cell that has no specific function but can develop into different types of cells

Question 10

Tissue stem cells

Answer 10

A TSC is an unspecialized cell that can divide and differentiate into specialized cell

Question 11

Embryonic stem cells

Answer 11

ESCs are pluripotent stem cells that can divide into more stem cells or become any type of cell in the body

Question 12

Organs

Answer 12

usually a combination of tissues that are coordinated to perform a variety of functions

Question 13

Systems

Answer 13

Are groups of organs which work together to form systems

Question 14

Multicellular

Answer 14

an organism that is made up of more than one cell

Question 15

Hierarchy of organisation

Answer 15

Cells –> Tissues –> Organs –> Systems –> Organism

Question 16

Stem cells are involved in?

Answer 16

growth and repair

Question 17

Organ examples

Answer 17

Stomach, leaf

Question 18

Tissue

Answer 18

is defined as a collection of cells, together that is specialized to perform one or more particular functions.

Question 19

Specialization of cells leads to the formation of a?

Answer 19

variety of tissues and organs

Question 20

Stages of mitosis

Answer 20

1. Chromosomes are hidden inside the nuclear membrane. A whole nucleus is visible
2. The nuclear membrane breaks down and chromosomes become visible. Each chromosome is double stranded (the two strands are identical and are called chromatids) spindle fibres form.
3. Spindle fibres attach to the centre of the chromosome and begin to jostle them into a line
4. Chromosomes line up at the equator (middle) of the cell
5. Spindle fibres pull one strand from each chromosome to each pole (end) of the cell
6. When the single stranded chromosomes reach the poles, a nucleus starts to form at each pole these nuclei are genetically identical.
7. At the very end of mitosis the cell will divide into 2 cells. Each of these carries exactly the same genes but they may use different genes e.g one may grow to become muscle tissue and another to from a nerve cell

Question 21

Cell division is controlled by the??

Answer 21

Nucleus

Question 22

Animal: Tissue, smooth muscle. Cell type?

Answer 22

smooth muscle cell

Question 23

Smooth muscle cells specialised structural features?

Answer 23

spindle shape (allowing cells to form sheets capable of contraction)

Question 24

Smooth muscle cell function

Answer 24

movement of food down oesophagus by peristalsis

Question 25

Blood, red blood cell specialised structural features?

Answer 25

carry oxygen (exp. carries oxygen as oxyhemoglobin, small enough to fit through capillaries.)

Question 26

Red blood cell function

Answer 26

uptake and transport of oxygen to living cells

Question 27

Stomach

Answer 27

churning and partial digestion of food

Question 28

leaf

Answer 28

photosynthesis and gaseous exchange

Question 29

Root epidermis, root hair cell features?

Answer 29

Long extension of an epidermal cell presenting a large surface area in contact with soil solution

Question 30

Root hair cell function?

Answer 30

absorption of mineral and water salts