lecture 11

Question 1

How long is the DNA’s length

Answer 1

6 ft

Question 2

What sections is the DNA library divided into

Answer 2

chromosomes

Question 3

What are the 4 bases of DNA

Answer 3

• Adenine
  -Thymine
  -Cytosine
  -Guanine

Question 4

What are genes a recipe for

Answer 4

proteins

Question 5

What is the cell membrane composed of

Answer 5

proteins and phospholipids

Question 6

Where does Transcription occur

Answer 6

In the nucleus, copies DNA

Question 7

Where does Translation occur

Answer 7

outside the nucleus in the cytoplasm

Question 8

How many chromosomes do we have ?

Answer 8

46 chromosomes

Question 9

What are chromosomes

Answer 9

pieces of DNA

Question 10

How are chromosomes made

Answer 10

when DNA is cut, it recoils into chromosomes

Question 11

what is a protein made up of

Answer 11

a sequence of amino acids

Question 12

How is a protein made

Answer 12

a gene in the DNA library is transcribed to make a copy of the gene (aka the mRNA)

mRNA leaves nucleus so that ribosomes can translate the mRNA into amino acids to make the protein structure

Question 13

The 4 properties of DNA

Answer 13

-replicate itself
-store information
-direct synthesis
-mutate

Question 14

What is DNA replication

Answer 14

the process of copying all of the cells genes to make a duplicate of the DNA library

Question 15

During replication what gets fully replicated and what doesnt

Answer 15

centromere gets fully replicated

telomeres do no fully replicate

Question 16

what is a telomere

Answer 16

the tips of the chromosome

Question 17

what is a centromere

Answer 17

the center of the chromosome

Question 18

are sex hormones proteins

Answer 18

no

Question 19

What happens to telomeres as they continue to duplicate

Answer 19

the telomere gets shorter and shorter

Question 20

What happens when a telomere is too short

Answer 20

the cell stops dividing and eventually dies

the shorter the telomere the more aging seen

Question 21

undifferentiated cells

Answer 21

no specific function, their telomeres never shorten so there no limit to cell division

cancerous cells mixed with normal ones

Question 22

differentiated cells

Answer 22

cannot keep their telomere at its original length, eventually reaches their limit for cell division and dies.

aggressive cancerous cells

Question 23

what part of the cell cycle does cell division occur in

Answer 23

M-phase (cell splits in two parts )

Question 24

What is Mitosis

Answer 24

the division of 1 nucleus into 2 nuclei

Question 25

What is cytokinesis

Answer 25

splitting a cell with 2 nuclei into 2 separate daughter cells

Question 26

What are the 4 steps of Mitosis

Answer 26

1. Prophase 2. Metaphase 3. Anaphase 4. Telophase

Question 27

What occurs in Prophase

Answer 27

*remember chromosomes are in the middle* centrioles double and move to opposite ends of nucleus centrioles form spindle fibers that attach to the nuclear membrane spindle fibers pull apart and nucleus disappears spindle fibers attach themselves to the exposed chromosomes

Question 28

What occurs in Metaphase

Answer 28

spindle fibers continue pulling exposed chromosomes chromosomes align

Question 29

What occurs in Anaphase

Answer 29

centromeres of all chromosomes replicate causing the chromosome to split in half spindle fibers keep pulling, causing separated daughter cells to gather at opposite parts of the cell

Question 30

What occurs in Telophase

Answer 30

Spindle fibers disappear New nuclear membrane reforms around each new set of daughter chromosomes at opposite poles of the cell 1 cell with 2 nuclei

Question 31

What occurs during cytokenesis

Answer 31

Occurs right after telophase Cytoplasmic membrane starts to pinch opposite sides to separate the 2 nuclei until they become 2 complete daughter cells

Question 32

what is interphase

Answer 32

the resting phase

Question 33

What is the epidermis

Answer 33

the top layer of the skin

Question 34

What is the top layer of the epidermis called

Answer 34

Stratum corneum, which is composed of dead epithelial cells filled with Keratin

Question 35

What is the Dermis

Answer 35

2nd layer, aka the active layer of skin containing : -blood vessels -nerve endings -hair follicle -oil glands -sweat glands

Question 36

What is the Hypodermis

Answer 36

3rd layer, composed of areolar or adipose tissue connecting the skin to the muscle

Question 37

What are the functions of the skin

Answer 37

-protect organism from microbes and dehydration -body temp regulation -collection of sensory information -production of vitamin d -excretion of electrolytes -absorption of some fat-soluble substances

Question 38

What are Decubitus Ulcers

Answer 38

Pressure sores, or bed sores develop when pressure is applied to a part of the body for a long period of time

Question 39

How many stages are there in bed sores

Answer 39

4 & it depends on the number of tissue layers affected

Question 40

Stage 1 of bed sores

Answer 40

only the epidermis is involved

Question 41

Stage 2 of bed sores

Answer 41

epidermis & dermis disintegrated

Question 42

stage 3 of bed sores

Answer 42

involves the pink muscle at the bottom of the ulcer

Question 43

Stage 4 of bed sores

Answer 43

involves all layers of tissue all the way to the bone