DNA, Cellular Specialization and Mitosis

Question 1

How many cells do adult humans have?

Answer 1

About 60 trillion

Question 2

What is a tissue?

Answer 2

Tissue is made up of specialized cells with the same function.

Question 3

What are the types of tissues? (4)

Answer 3

• Epithelial
• Connective
• Muscle
• Nerve

Question 4

What is the function of epithelial tissue? Where can we find it?

Answer 4

Function: It covers and protects the outside and the inside of the body. Absorbs, secretes and filters.
Locations: Skin and digestive tract lining

Question 5

What are the functions (2) of connective tissue? Where can we find it?

Answer 5

Functions: It binds and supports tissues and organs. It also provides protein and nutrients.
Locations: Bone tissue

Question 6

What are the functions (2) of nerve tissue? Where can we find it?

Answer 6

Function: It guides and controls body activity. It receives stimuli and transmits messages.
Locations: Spinal cord and nerves

Question 7

What are the functions (2) of muscle tissue? Where can we find it?

Answer 7

Functions: It allows the body to move. It can contract and regain shape.
Locations: Organs, heart, skeleton

Question 8

What are the 3 types of muscle tissue?

Answer 8

• Smooth (organs)
• Cardiac (heart)
• Skeletal (bones)

Question 9

What is an organ? (+ Examples)

Answer 9

An organ is a group of different tissues made to do one function.
Examples: stomach, liver, lungs, etc.

Question 10

What is a system? (+ Examples)

Answer 10

A system s a group of organs and tissues working together to accomplish a common goal.
Examples: Respiratory, cardiovascular, circulatory, lymphatic, digestive, nervous, reproductive, excretory, endocrine (hormones), etc.

Question 11

Give the order or cellular organization. (Smallest to largest)

Answer 11

Cell → Tissue → Organ → System → Organism

Question 12

What is responsible for keeping us alive?

Answer 12

Cells

Question 13

Why do cells divide? (3)

Answer 13

1) Increase cell count for growth
2) Regenerate damaged tissue
3) Makes sexual reproduction possible

Question 14

What are the two phases of the cell cycle?

Answer 14

• Interphase

- M Phase (Mitosis)

Question 15

What happens during interphase? (3)

Answer 15

The cell is getting ready to divide. DNA is replicating.

• G1 phase: Growth + preparing DNA for replicating
• S phase: Synthesis (DNA replicating)
• G2 phase: Growth

Question 16

What happens during the M phase? (4)

Answer 16

Actual cell division
P → Prophase 
M → Metaphase 
A →  Anaphase 
T →  Telophase

Question 17

What are chromosomes?

Answer 17

Rod-like structures made of condensed DNA strands

Question 18

What are the parts of chromosomes?

Answer 18

• Each rod is a chromatid
• The center where the two rods meet is called the centromere.
• Each one is an exact copy
  (Chromatid: I, Chromosomes: X, • : Centromere)

Question 19

What are chromosome pairs?

Answer 19

We have 46 chromosomes, 23 from each parent.

Question 20

Explain the 22 numbered chromosomes, as well as the 23rd.

Answer 20

• 22 of your chromosomes are numbered

- The 23rd determines biological gender (XX=F, XY=M)

Question 21

What are the 4 bases of your DNA?

Answer 21

• Adenine
• Guanine,
• Cytosine
• Thymine

Question 22

How do the base pairs bind?

Answer 22

• Adenine + thymine

- Cytosine + guanine

Question 23

What do the base pairs hold?

Answer 23

Genetic material

Question 24

How many possibilities are there for base pairs? How many genes exist?

Answer 24

• 3 billion base pair sequences

- 100 000 genes

Question 25

What is a genome?

Answer 25

The complete set of genetic information of an individual or species.

Question 26

What is a gene?

Answer 26

A segment of DNA that contains the genetic information required to carry out a particular job.

Question 27

How many genes does the human body have?

Answer 27

30 000 genes

Question 28

What does each gene contain?

Answer 28

Each gene contains the necessary information to make proteins. Each protein has a specific job.

Question 29

What are proteins responsible for? (3)

Answer 29

• Physical features
• Hormones
• How we develop

Question 30

Give the organization for genetic material. (Smallest to largest)

Answer 30

DNA → Genes → Chromosomes → Genome

Question 31

Why does genetic diversity exist?

Answer 31

Every gene can exist in different variations which is what gives us our unique look.

Question 32

What increases genetic diversity?

Answer 32

Sexual reproduction. The bigger the population, the more diverse it is.

Question 33

What is mitosis?

Answer 33

The cell division process that leads to a diploid cell. (Diploid means 2!)

Question 34

What’s the difference between haploid and diploid cells?

Answer 34

Diploid cells have 2 copies of each gene.
All human cells are diploid except for the sex cells.
Sex cells are haploid. (Haploid means ½ info, 1 copy of each gene)

Single rods → haploid cell
Pairs of rods → diploid cell

Question 35

Why do cells multiply in this process?

Answer 35

To ensure growth and tissue repair. (Ex: Muscle tissue, epithelial tissue).

Question 36

What happens in the prophase?

Answer 36

Prophase → “Pre = Before”

• The DNA condenses
• The nuclear membrane disappears

Question 37

What happens in the metaphase?

Answer 37

Metaphase → “Middle”

- Chromosomes Align (form a line in the MIDDLE)

Question 38

What happens in the anaphase?

Answer 38

Anaphase → “Away”

• Splitting of the chromosomes
• Detach (ANA means to move back)

Question 39

What happens in the telophase?

Answer 39

Telophase → “Two”
- New nuclear membranes are formed
- The DNA condenses
The cell divides in 2!
2 copies of each gene

Question 40

What is the result of “PMAT” (Mitosis/M Phase)?

Answer 40

Result → 2 daughter cells that are diploid

Question 41

What do we call it when cells split?

Answer 41

Cytokinesis