Unit 4: Dna and Rna, Dna replication, Protein Synthesis, meiosis, Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what is dna and rna

A

they are nucleic acids, both made of nucleotides.
- sugar
- phosphate
- nitrogenous bases

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

what are the nitrogenous bases

A

adenine (a), thymine (t dna only), guaine (G), cytosine (c), Uracil (u rna only)

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

what does dba do

A

stores genetic information using its sequances of A, T, C, G

  • this genetic information is the instructions to make an organisms proteins ( ex. like a recipe book for proteins)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does dna stand for

A

deoxyribonucleic acid

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

what is the dna structure and what is it made out of.
What are the nitrogeneous bases for DNA

A

it has a double helix shape ( twisted ladder)
- deoxyribose sugar
- A,T,C,G

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

where is dna stored

A

the nucleous of eukaryotes

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

-what does Rna do

A

helps DNA make proteins

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

what are the 3 types of rna and what do they do

A

EACH ONE HAS ITS OWN JOB
- mRNA : carries DNA message as codons
- rRna: makes up ribosomes
- trna: matches anti-codon to mRna codon to bring the correct ameino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  • what does rna stand for
  • what is the structure of DNA
A
  • Ribonucleic acid
  • rna is single stranded
  • made of ribose sugar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the nitrogenous bases for rna and where is it found

A
  • A, U, C, G
  • nucleus and cytoplasm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how do the nitrogenous bases connect

A
  • held together by hydrogen bonds
    In both: c-g
    dna: a-t
    rna- a-u
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

explain DNA replication

A

process of making a copy of DNA
- the DNA made during replication Is the exact same copy of the original DNA
- THIS HAPPENS IN S-PHASE OF INTERPHASE

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

explain semiconservative

A

each DNA molecule consists of an original strand and a new strand

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

what does dna require to replicate

A

it requires many enzymes ( proteins )

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

what does the following do:
- helicase
- DNA polymerase
- ligase

A

helicase - separates DNA strands
Dna polymerase- adds nucleotides + proofreads
ligase- links new pieces of dna

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

what is the central dogma

A

explains how life is determained threw DNA
DNA < RNA < proteins

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

what is a gene

A

a section of dna that codes for a protein is called a gene
- the gene is read, and the message is used to make a protein

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

what is photosynteisis

A

process of making proteins
2 steps: transcription and translation

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

what is trancscription

A

1) mRna copies dna instructions

20
Q

what is translation

A

2) ribosomes use mRNA to make proteins

21
Q

Transcription
location:
what is invloved:
what happens:

A

location: nucleous
what is invloved: dna + rna
what happens:
- DNA unwinds where gene is
- rna polymers use DNA as a template to ake an mRna copy
- now the mRna copy can leave the nucleus

22
Q

what is a codon

A

sequance of 3 nucleotides that code for an ameino acid
- AUG is the start codon

23
Q

Translation
- location
- what
- what happens

A
  • ribosomes
  • mrna, ribosome (mRna), Trna
  • mRna finds a rubosome and binds to it, mrna codons are read by tRna.
  • tRna brings in correct AA that matches codon. aneino acid links together to form protein
24
Q

describe somatic cells

A
  • Body cells
  • found in body tissue + organs
  • Dna in body cells arent passed to offspring
  • ex. nerve cell
25
Q

describe gamates

A
  • sex cells
  • eggs (female) sperm ( male)
    -dna in gamates can be passed to an offspring
26
Q

describe a chromosome

A

a condensed dna molecule with part (or all) of the genetic material of an organism
- humans have 23 pairs ( 46 in total)

27
Q

there are 2 types of chromosomes: autosomes + sex chromosomes. describe them

A

autosome- chromosomes that carry traits
sex chromosome- chromosomes with genes related to biological sex
- XX = female
-XY= male

28
Q

what are homologous chromosome

A

2 chromosomes with the same genes, but may have different versions of genes ( alles)
- 1 is from mother
-1 is from father

29
Q

what is a Diploid

A

(2n) - these cells have 2 copies of each chromosome
- somatic cells
- have homologous chromosomes

30
Q

what is a haploid

A

(n) think half- these cells have only 1 copy of each chromosome
- gamates
- don’t have homoglous chromosomes

31
Q

what is fertilization

A

uniting of a sperm and and egg cell
- results in a diploid
- zygote = fertilized egg

32
Q

mitosis

A

starts with one 2n cell + ends with two 2n cells
- somatic cells = more somatic cells

33
Q

meiosis

A

starts with one 2n cell and ends with four 2n cells
- somatic cells= sex cells (gamates)
- meiosis produces 4 sex cells that are genetically different from one another and from original cell
- cells go through 2 rounds of division
- results in haploid cells
- reduceses chromosomes by half
- only happens in sex cells

34
Q

Meiosis 1

A

seperates homologous chromosomes
( moms set seperates from dads set)

35
Q

Interphase 1

A
  • G1: cells grow and preform many of their required cellular functions
    -S-phase: DNA us copied/ replicated
  • G2: makes proteins, grows
36
Q

prophase 1

A

The nuclear envelope breaks down. The chromatin condenses into chromosomes.
- crossing over occurs

37
Q

metaphase 1

A
  • homologous chromosomes pairs are randomly lined up in middle of cell
  • chromosomes are lined up along each side of cell equator
    -independant assortment
38
Q

anaphase 1

A

chromosomes are in pairs and are pulled away by spindle fibers
-sister chromotids remain toghther

39
Q

teleophase 1

A

-nuclear membrane forms again (some species)
- spindle fibers dissasimble
- cell undergoes cytokenisis
END RESULT: two new haploid cells w duplicated chromosomes. 46 chromosomes

40
Q

what are the two mechanisms that occur during meiosis 1

A

genetic diversity and variation

41
Q

what is crossing over

A
  • homologous pairs line up on opposite sides of equator, parts of chromotids and become twisted around each other
  • this results in a new combination of alleles
42
Q

what is independent assortment

A
  • homologous pairs line up opposite sides of equator
  • randomized
  • pairs are separated, 1 of each homologous pair ends up in daughter cell
    – creates large number of possible combinations of chromosomes in daughter cells produced
43
Q

prophase 2

A
  • nuclear membrane breaks down
    -spindle fibers assemble
44
Q

metaphase2

A

spindle fibers align chromosomes at cell equatpr
- each chromosome still has two sister chromotids

45
Q

anaphase 2

A

-sister chromotids are pulled apart from each other by spindle fibers

46
Q
A