Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Topic 2- genes and health > Flashcards

Topic 2- genes and health Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Describe and explain the effect alcohol concentration has on membrane permeability

A

Solvents such as ethanol increase membrane permeability. Lipids dissolve in alcohol, therefore, the phospholipids in a cell membrane will easily dissolve in solutions such as ethanol. As a result, the cell membrane becomes more fluid and permeable as it starts to break down.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe and explain the effect temperature has on membrane permeability

A

The higher the temperature, the greater the kinetic energy and the faster the movement and diffusion of pigment molecules. Greater kinetic energy also causes phospholipids of the membrane to become more fluid and bonds between the fatty acid tails can begin to separate so that some pigment molecules can pass through.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Explain the effects of CF on the digestive system

A

block pancreatic duct
enzymes not released to small intestine- less digestion
enzymes begin to digest pancease= hard cysts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain the effects of CF on the reproductive system, incl. both males and females

A

-female thicker mucus plug on cervix- sperm cant enter
male- the vas deferens is blockedor non existent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain the effects of CF on the respiratory system

A

thicker muscus (insert why) cant be moved along by cillia
makes diffusion distance longer
less oxygen enters blood
less respiration
less energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain how a faulty CFTR protein results in thicker, stickier mucus in CF sufferers

A

-ion channel is open as well as the CFTR channel being open/non existent
-water is constantly osmosis out of the mucus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain the role of the CFTR protein

A

maintain the balance of Na+ and water in mucus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain how and why the hydrolysis of amylopectin/glycogen stored in a cell would impact the movement of water via osmosis

A

less water in cell, so more would enter cell theough osmosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Under what conditions would water move into a cell via osmosis?

A

If a plant cell is surrounded by a solution that contains a higher concentration of water molecules than the solution inside the cell, water will enter the cell by osmosis

hypotonic solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Under what conditions would water move out of a cell via osmosis?

A

If a cell is in a hypertonic solution, the solution has a lower water concentration than the cell cytosol, and water moves out of the cell until both solutions are isotonic

hypertonic solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give a definition of osmosis

A

a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain how saturated and unsaturated phospholipid tails affects membrane fluidity

A

unsturated=less compact= more fluidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Explain how the level of cholesterol affects membrane fluidity

A

more cholesterol=less movement (holds tails togther)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Explain why the cell membrane is called a fluid mosaic

A

multiple moving components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

List the other components of cell membranes and give a function for each

A

Transmembranic Channel protien- allows larger molecules to enter the cell through
cholesterol- provides strength by holding tails together and regulates fluidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain why phospholipids form a bilayer in cell membranes

A

head is hydrophilic and faces outwards
tail is hydrophobic and faces inwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the structure of a fibrous protein

A

-long fibers of alpha helix secondary structure
-cross linked for strength
-insoluble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the structure of a globular protein

A

-spherical 3d shape
-insoluble
-can have specific shape for function (enzymes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Give the formula for Fick’s Law

A

rate of diffusion= surface area x concen dif
thickness of gas exchange sufface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Explain the anatomical adaptations in organisms with respiratory systems that maximise gas exchange (make specific reference to surface area:volume ratio, thickness of exchange surface and concentration gradient)

A

avioli in lungs

surface area: volume ratio - more space for diffusion
thickness of surface- shorter diffusion distance
higher concerntration gradient- faster diffusion rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Explain the role of ciliated epithelial cells in the respiratory system

A

transports mucus- traps pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Explain the role of goblet cells in the respiratory system

A

has a higher surface area due to dip shape

secrete mucin and create a protective mucus layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe how the tertiary structure of a protein forms from the secondary structure

A

provides a 3d shape as the R goups with different charge form ionic bonds, further hydrogen bonds and disulphide bridges are further support as just hydrogen isnt strong enough (written as S-S)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe how the secondary structure of a protein forms from the primary structure (make reference to alpha helix and beta pleated sheets)

A

primary structure is folded as either a alpha helix or beta pleated sheet by forming hydrogen bond between the carboxyl and NH groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Give a definition of the primary structure of a protein

A

the order of amino acids in a polypeptide chain

26
Q

Describe how amino acids react together to form a polypeptide

A

condensation reaction between amino acids forming a peptide bond between the NH and carboxyl groups of different amino acids

27
Q

Draw the structure of an amino acid, circle and label the functional groups

A

H R OH
\ | //
N-C-C
/ | \
H H H

28
Q

Describe the structure of a DNA mononucleotide

A
  • Phosphate group
  • Deoxyribose sugar (pentose sugar)
    -Nitrogen containing base
29
Q

Describe how DNA mononucleotides join together to form a DNA polymer/strand

A

Condensation reaction between sugar and the phosphate group

form a sugar phosphate backbone

30
Q

Describe the structure of a RNA mononcleotide

A
  • phosphate group
  • Nitrogen containing base
  • ribose sugar (pentose sugar)
31
Q

Describe how DNA forms a double helix

A

through complimentary base paring of C and G and A and T with hydrogen bonds

2 antiparallel strands join at the base

32
Q

Describe the process of DNA replication

A

1) DNA helicase unwinds and unzips DNA, breaking the hydrogen bonds between base pairs, forming two separate strands that act as a template

2) The new DNA is built up from the 4 nucleotides in the nucleus

3) The nucleotides attach themselves to the bases on the old strands by complementary base pairing

4) DNA polymerase joins the new nucleotides to each other by strong phosphodiester
bonds, forming the sugar phosphate backbone

5) the two new molecules are identical to the old one

1)Helicase
2) nucleotides
3) complementary
4) polymerase
5) identical

33
Q

Explain how Meselson and Stahl’s experiment refuted the conservative model of DNA replication

A

An explanation which includes the following:
• The conservative model was rejected / the semi-conservative model was accepted (1)
• (due to) generation 1 has a single band which is halfway between 15N and 14N (1)
•
•
(because) the DNA has one strand containing 15N and one strand containing 1N (1)
(in semi-conservative model) further generations would have {a band which is halfway between 15N and
14N / no band at 15N } (1)

34
Q

Explain how Meselson and Stahl’s experiment refuted the dispersive model of DNA replication

A

• The dispersive was rejected / the semi-conservative model was accepted (1)
• (due to) generation 1 has a single band which is halfway between 15N and 14N (1)

•
(because) the DNA has one strand containing 15N and one strand containing 1N (1)
(in semi-conservative model) further generations would have {a band which is halfway between 15N and
14N / no band at 15N } (1)

dispersive was not pogging because there was a spilt between the heavy and light dna

35
Q

2) Explain how Meselson and Stahl’s experiment provides evidence for the semi-conservative model of DNA replication

A

They cultivated bacteria colonies in one growth medium containing heavy nitrogen (N-15) and one growth medium containing light nitrogen (N-14).

they then extracted dna from the bacteria from both growth mediums and put them into separate vials. they spun these vials in a centrifuge.

The dna cultivated in the heavy nitrogen settled low down in its vial, whereas the dna cultivated in the light nitrogen settled high up in its vial.

The scientists then transferred some of the bacteria that had been cultivated in the heavy nitrogen into a growth medium containing light nitrogen. they let the bacteria grow for 1 generation and then extracted the dna from it.

They spun this dna in a centrifuge and it settled halfway between where the n-14 and n-15 dna settled.

They let the bacteria grow in the n-14 growth medium for another generation, and spun it in the centrifuge. They repeated this for 5 generations. They found that after the second generation, the amount of dna that settled at the midpoint stayed the same, but an increasing number of dna molecules began to settle at the N-14 line again.

This provided evidence for the semi conservative model as it shows that after the first generation, each dna molecule was made of a split of heavy and light nitrogen as the dna settled at the halfway point between heavy and light, which disproved the conservative theory.

It also provided evidence for the semi conservative model as each increasing generation began to gather at the light nitrogen line, while the number of dna molecules at the midpoint stayed the same. This shows that each generation conserves the strand of heavy nitrogen dna along with producing new strands of dna using the light nitrogen from the growth medium.

36
Q

Describe the process of transcription

A

-DNA helicase unzips a section of dna by breaking the Hydrogen bonds and exposing the bases, into two strands were one is used as a template
- complimentary base pairing occurrs but Uracil replaces T in the mRNA
-RNA polymerase joins up the RNA making a mRNA molecule
-RNA polymerase stops making mRNA when it reaches a stop signal on the DNA molecule
- Once the mRNA has been made, the DNA strands coil back and hydrogen bonds reform
-mRNA moves out of the nucleus, into the cytoplasm where it attaches to a ribosome

37
Q

Describe the process of translation

A

-Occurs in the ribosome in the cytoplasm
-mRNA bonds to ribosome
-tRNA with anticodon and a specific amino acid binds to codon via complimentary bade paring
-adjacent amino acids join via condensation reactions forming peptide bonds
-process stops when the primary structure of the protein is completed

38
Q

define codon and anticodon

A

codon is:
Three bases on mRNA which code for one amino acid

anticodon is:
Three bases on tRNA, complementary to mRNA codon

39
Q

Describe the nature of the genetic code by defining the following:
a) degenerate
b) triplet code
c) non-overlapping

A

Degenerate
Most amino acids have more than one codon that relates to them

Non-overlapping
Each base is only read once
Eg ABCDEF is ABC DEF not ABC CDE

Universal
All organisms use the same code, so the same codon always codes for the same amino acids

40
Q

1) Give the definition of a mutation

A

change in the arrangement of bases in DNA

41
Q

Describe the nature of the genetic code by defining the following:
a) degenerate
b) triplet code
c) non-overlapping

A

a) degenerate- amino acids can have multiple codons that corespond to them
b) triplet code- three bases code for an amino acid
c) non-overlapping- each base is only counted once

42
Q

Give the definition of a mutation

A

a change in the arrangement of bases in a DNA molecule

43
Q

Explain the impact of a frameshift mutation on protein structure

A

a base is inserted or deleted from DNA, which shifts the whole code from that point, changing every triplet and therefore changing the amino acids that bind to them

44
Q

Explain why accurate DNA replication is important for protein synthesis

A

so the order of amino acids is correct, meaning the correct protien is made

45
Q

Explain the impact of a silent mutation on protein structure

A

nothing, a base is replace by another but dna is degenerate

46
Q

Explain the impact of a missense mutation on protein structure

A

changes only one amino acid therefor unlikely to impact overall protein structure

47
Q

Explain the impact of a nonsense mutation on protein structure

A

protien too short as the mution caused a stop codon in a base sequence

48
Q

define Genotype

A

combination of alleles an individual has

49
Q

define Phenotype

A

Characteristic caused by the genotype and evrioment

50
Q

define Homozygous

A

Two copies of the same allele

51
Q

define Heterozygous

A

Two different alleles in the genotype

52
Q

define Recessive gene

A

Only expressed in the phenotype if the individual is homozygous for the allele

53
Q

define Dominant allele

A

Expressed in the phenotype if one of these alleles is present in the genotype

54
Q

define Incomplete dominance

A

Each allele equally expressed in the phenotype

55
Q

define Gene

A

Sequence of DNA bases that codes for a sequence of amino acids in a polypeptide

56
Q

define Allele

A

Alternative form of a gene found at the same locus (position on chromosome)

57
Q

Give the genotype of an individual who is a symptomless carrier of a recessive disease

A

heterozygous

58
Q

State the differences between the two categories of cell: eukaryotic and prokaryotic cell

A

..

59
Q

Using a diagram, identify the following features of a prokaryotic cell: peptidoglycan cell wall, capsule, plasmid, flagellum, pili, ribosomes, mesosomes and circular DNA
give a function for each

A

…

60
Q

name the organelles in Eurakyotic cells

A

-nucleus
-cell surface membrane
-mitochondria
-Centrioles
-rough/smooth endoplasmic reticulum
-Lysosomes
-Golgi

Biology (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions