Part 3 - Mutations/Lac operon/Tissues

Question 1

What are 5 animal tissues?

Answer 1

Epithelium
Connective
Muscle
Nervous
Cellular junction

Question 2

Why do mutations happen?

Answer 2

Hereditary change

Change/shift in nucleotide sequences

Question 3

Why is there lethal mutations?

Answer 3

Vital function of the organism is altered (ex. organelle function or organ system function)

Question 4

Why is there non-lethal mutations?

Answer 4

The functions are not altered / gene that is not activated is not an essential gene, or other gene types produce some gene product that offsets the essential gene

Question 5

What are the types of mutations?

Answer 5

Point, Frame shift, Deletion

Question 6

What is point mutation?

Answer 6

attCgcatc
attAgcatc
change of the nucleotide

Question 7

What is frame shift mutation?

Answer 7

agc Ttt aag ccct
agc Gtt taa gcc t
shift

Question 8

What is deletion mutation?

Answer 8

agc ttT aag ccc
agc tta agc cc
the nucleotide is deleted

Question 9

What is the repair mechanism against mutations?

Answer 9

Complimentary DNA
Nucleases cut out a chunk of DNA on either sides of the mutations creating a break, DNA polymerase will insert new nucleotide instead of mutation and will will replace the incorrect nucleotide. DNA ligase will patch up the correct strand

Question 10

What is gene control?

Answer 10

Genes are under regulatory control and moderated by regulatory proteins
Repressor protein (prevents expression) - negative control - and Activator protein (activates expression) - positive control
*think of lactose in milk that is being consumed

Question 11

What is lactose operon?

Answer 11

Involved in the metabolism of lactose by bacteria

Lactose = glucose + galactose

Question 12

What are the three genes to break down the sugar?

Answer 12

LacZ, LacY, LacO (LacA)
They are structural genes
must be controlled in some way

Question 13

Negative control of the lac operon

Answer 13

low C of lactose - lac operon not active - no gene expression
due to repressor protein
high C of lactose - lac operon is active - gene expression
due to the binding between repressor and lactose
makes the protein flow away, lets the RNA polymerase to attach
as follows the C of lactose will go low - lac operon will become inactive again

Question 14

Positive control of the lac operon

Answer 14

high C of glucose - lac operon is inactive
lactose will bind to the repressor that will flow away, but RNA polymerase cannot stay at its place, needs to be hold, so it needs activation protein - CAP (holds RNA polymerase)

Question 15

How does CAP become activated?

Answer 15

cAMP activates CAP by binding to it

cAMP comes from ATP - from glucose through adenylate cyclase

Question 16

Skeletal muscle

Answer 16

Contains actin and myosin
Contractile
Striated
Bone tissue only

Question 17

Cardiac muscle

Answer 17

Unique
Heart only
Striated
Striations are held together by gap junction (for efficient blood flow)

Question 18

Smooth muscle tissue

Answer 18

non-striated
gap junctions (slow contractions of muscles for efficient peristalsis)
found in arteries
found in intestinal tract
involuntary muscles

Question 19

Connective tissue

Answer 19

1. Soft
   Loose connective
   fibroblast, ground substance, chondroitin
   supporting epithelium and respiratory tract, provides support and protection
   Dense regulatory CT
   fibroblasts that lie in bundles with each other
   parallel layers of collagen secreted (form tendon)
   connects muscle tissue to the bone
   Dense irregular connective tissue
   fibroblast are held all over the place, overlapping with each other, dermis layer of skin
2. Specialized
   Cartilage
   release of chondroitin
   all wrapped up in chondroitin - absorbs force (jelly layer)
   Bone
   Fibroblasts that form collagen and chondroitin that from matrix - creates Ca3(PO4)2 deposits that make the tissue very hard
   Adipose CT
   fat, fibroblasts contain a lot of lipids with droplets
   Blood
   fluid plasma, contains proteins, ions, water
   cells, various types of blood cells, platelets

Question 20

What is nervous tissue?

Answer 20

tissue that responds to the environmental alterations
external or internal
cells - neurones

Question 21

Types of neurones

Answer 21

Movement of sensory information
Monopolar - dendrite down to axon encounters cell body, down the axon to terminal button
Bipolar - direct contact through the axon or cell body
Multipolar - cell body around it fibrous dendrites receive info and transfer down to the terminal

Question 22

Types of neurones (based on function)

Answer 22

Sensory receive input and relays to another place (interneurone) then to motor neurone (activates/initiates movement/reaction)

Question 23

What does cytoplasm of the neurone contains?

Answer 23

K.
more Na in extracellular than in side, more K inside then in extracellular fluid
Two electrochemical gradients

Question 24

What is a tissue?

Answer 24

Collection of cell types that carries out a specific function
Organ is a collection of several types of tissues, but also carries outa specific function

Question 25

What is gene amplification?

Answer 25

Genes are duplicated Multiple copies of gene product (mRNA) are produced by RNA polymerase *for many transcripts of the gene

Question 26

Chromosome puff

Answer 26

Fruit fly Ecdysone - nuclear membrane - DNA Nucleosomes start to unwind due to a signal, creates chromosome puff, exposes DNA, multiple chromosomes of the genes in the strand, amplification and duplication of the genes

Question 27

What is somatotropin (growth hormone) and what is it for?

Answer 27

It binds to DNA, causes production of genes that produce proteins, which trigger mitosis ex. injecting it into a cow makes her be both bigger and heavier

Question 28

Types of epithelial tissues?

Answer 28

Sheet structure epithelium linings of organs, surface of organisms External epithelium usually referred to stratified epithelial, two layers of cells, protection role Internal epithelium organs, glands, simplified (1 layer), absorbs nutrients, allows wastes to be removed

Question 29

What are cell junctions and its types?

Answer 29

Tight junction Gap junction (protein tubes formed by protein connections, cytoplasm of one junction is connected to the cytoplasm of the other - for intercellular communication) Desmosome (Adhering Junction) held together by tonofilaments that penetrates the membrane and makes contact with a protein deposit called plaque (anchors the filaments together)

Question 30

What are the types of epithelial cells?

Answer 30

Squamous cell (found in capillaries, thin, flat, allows diffusion of O2 and CO2) Columnar cell (Lines the gut in animals, column shaped, longer and wider, tip is microvilli, exchange of materials in the lumen) Cuboidal cell (cube, has microvilli, associated with glands and kidneys, involved in excretion)

Question 31

What are glands types?

Answer 31

Ductless gland (exocrine gland, releases hormones - just a chemical signal, influences the cell activity of other cell types) Duct gland (endocrine gland, saliva, mucous)