Brainscape's Knowledge GenomeTM

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


See full index

MCAT > Biology > Flashcards

Biology Flashcards

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

Do prokaryotic cells contain a nucleus?

A

NO!!!

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

Membrane-bound Organelles found in eukaryotic, prokaryotic, or both?

A

ONLY EUKARYOTES

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

The nucleolus is…

A

A subsection of the nucleus where ribosomal RNA (rRNA) is synthesized!!

rRNA – RNA component of ribosomes

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

Cytoplasmic/Extranuclear Inheritance

A

the transmission of genetic material independent of the nucleus

MITOCHONDRION – contain own genes and replicate independently of the nucleus through binary fission

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

Apoptosis

A

MITOCHONDRION

release enzymes from the ETC kickstarts apoptosis

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

Difference between rough ER and smooth ER?

A

Rough ER studded with ribosomes and translated proteins.

Smooth ER used for lipid synthesis and detoxification. Also transports proteins from RER to Golgi.

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

Primary function of a peroxisome?

A

breakdown of very long chain fatty acids via beta oxidation

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

Microfilaments

A

Component of the cytoskeleton. Solid polymerized rods of actin. RESISTANT TO COMPRESSION OR FRACTURE. Interact with myosin to generate movement.

Role in CYTOKINESIS (division of material between daughter cells). Creates cleavage furrow between two daughter cells (ring of actin filaments).

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

Microtubules

A

Component of cytoskeleton. Hollow polymers of tubulin. Pathway for KINESIN and DYNEIN.

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

What is the 9+2 structure?

A

Pertaining to the structure of cilia and flagella. Composed of nine pairs of microtubules forming an outer ring with two microtubules in the middle.

ONLY IN EUKARYOTES

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

Centrioles

A

Found in the CENTRISOME. Organize the mitotic spindle on opposite ends of cell. Microtubules emanate from centriole and attach to chromosome via the KINETOCHORE.

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

Parenchyma

A

The functional parts of an organ. Comprised of EPITHELIAL cells in many organs. Attached via basement membrane.

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

Stroma

A

The support structure of an organ for the endothelial cells. Comprised primarily of CONNECTIVE TISSUE.

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

Nucleoid Region

A

Found in PROKARYOTES.
Region where the single circular molecule of DNA is found.

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

Obligate Aerobe

A

bacteria that require oxygen for metabolism

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

Obligate Anaerobes

A

bacteria that cannot survive in an oxygen-containing environment

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

Facultative Anaerobe

A

bacteria that can toggle between aerobic and anaerobic respiration depending on what’s available

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

Describe the membrane/outside of a prokaryote.

A

CELL WALL outer barrier of the cell
CELL/PLASMA MEMBRANE

these together are known as the ENVELOPE of the prokaryote

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

Gram-positive vs gram-negative prokaryotic cell walls.

A

Gram-Positive: thick layer of peptidoglycan (PURPLE) and lipoteichoic acid

Gram-Negative: very thin layer of peptidoglycan separated by periplasmic space (PINK) and lipopolysaccharides

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

Plasmids

A

carry DNA in prokaryotes NOT NECESSARY for survival

NOT part of the genome

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

ETC in prokaryotes.

A

They lack mitochondrion

Instead, use the cell membrane for the ETC.

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

Ribosomal difference between eukaryotes and prokaryotes.

A

Prokaryote: 30S and 50S (SMALLER)
Eukaryotes: 40S and 60S (LARGER)

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

A subset of plasmids capable of integrating into the genome of a bacteria cell?

A

Episome

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

Transformation

A

integration of foreign genetic material into the host genome

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

Conjugation

A

Sexual reproduction in bacteria. Unidirectional via a conjugation bridge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is a Hfr (high frequency of recombination) bacterium formed?

A

The sex factor is integrated into a bacterium genome. The conjugation bridge breaks before the entire copy of the genome is transferred to the recipient. This bacterium is now Hfr.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Transduction

A

only genetic recombination process that requires a vector – virus carries material from one to another.

BACTERIOPHAGE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Transposon

A

genetic elements capable of inserting and removing themselves from the genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Growth Phases of a Bacterial Colony

A
  1. Lag Phase
  2. Exponential (Log) Phase
  3. Stationary Phase
  4. Death Phase

via binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Capsid

A

Protein coat of a virus which may be surrounded by an envelope composed of phospholipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Enveloped Virus

A

EASIER TO KILL (prone to heat, detergents, and desiccation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Virion

A

the viral progeny produced in an infected host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Negative-sense RNA viruses

A

MUST carry with them an RNA replicase in the virion to ensure complementary RNA strand is synthesized

34
Q

Retrovirus

A

ENVELOPED
SINGLE-STRANDED RNA

carry the enzyme reverse transcriptase (synthesizes DNA from the RNA) – this then integrates into the host genome

35
Q

Enzyme responsible for creating complementary RNA (+) from a negative sense RNA virus.

A

RNA replicase

36
Q

Lytic Cycle

A

bacteriophage maximizes the use of the cell’s machinery without regard for life

busts out the hoe like a bomb

very virulent

37
Q

Lysogenic Cycle

A

integration into the host genome or acts as a prophage (exits the cell but keeps it intact)

acts as a sneaky bastard and gets replicated

superinfection

38
Q

Prions

A

infectius proteins due to triggering the misfolding of other proteins

usually through conversion of alpha helix to a beta-pleated sheet

39
Q

Cytokinesis

A

the cytoplasmic division in eukaryotes at the end of mitosis (cell separation)

invagination of the cell membrane

40
Q

How many chromosomes do humans have?

A

46 total (autosomal cells // two copies of each chromosome) [diploid]

23 from each parent (germline cells // haploid)

41
Q

Which stages of the cell cycle make up interphase? What is interphase?

A

G1, S, and G2

longest part of the cell cycle

42
Q

What stage of the cell cycle are cells that don’t divide in?

A

An off shoot of G1 called the G0 stage.

43
Q

What form are chromosomes in during interphase?

A

less condensed version called CHROMATIN

must be available to RNA polymerase

44
Q

G1 Stage of the Cell Cycle

A

Presynthetic Gap

cells create organelles

passage to the S stage is governed by a restriction point

45
Q

S Phase of the Cell Cycle

A

Synthesis of DNA

cell replicates its genetic material

chromatids bound together at the centromere

46 chromosomes with 92 chromatids (2x DNA than G1 cells) organized into 23 homologous pairs

46
Q

G2 Stage of Cell Cycle

A

Postsynthetic Gap

quality control checkpoint for DNA replication before cell divides

47
Q

M Stage of the Cell Cycle

A

NOT Interphase

Mitosis

mitosis and cytokinesis

48
Q

G1/S and G2/M checkpoints in the cell cycle regulated by what?

A

p53 main protein responsible to check if the condition of the DNA is good enough for synthesis

49
Q

What is one of the most common mutations found in cancer?

A

mutation of the gene TP53

the gene that produces the p53 protein

50
Q

Prophase (Mitosis)

A

chromosomes condense and spindle forms

centrosomes – microtubule organizing center – migrate to ends of cell

kinetochores

51
Q

Metaphase (Mitosis)

A

chromosomes align at the metaphase plate (equatorial plate)

52
Q

Anaphase (Mitosis)

A

sister chromatids separate

kinetochore fibers shorten

53
Q

Telophase (Mitosis)

A

new nuclear membranes form

cytokinesis

53
Q

Telophase (Mitosis)

A

new nuclear membranes form

cytokinesis

54
Q

Meiosis I vs Meiosis II

A

Meiosis I results in homologous chromosomes separating (haploid daughter cells) (reductional division)

Meiosis II results in the separation of sister chromatids without a change in ploidy (equatorial division // more similar to mitosis)

55
Q

Mitochondrial DNA

A

CIRCULAR and SELF-REPLICATING

56
Q

Which organelles are surrounded by a single membrane and which are surrounded by a double membrane?

A

SINGLE: lysosome
DOUBLE: mitochondrion and nuclei

57
Q

A virus needs to be transported into the nucleus in order to synthesis viral proteins. What is the genomic content of the virus?

A

DNA virus!!!

only DNA virus need host nuclear RNA polymerase

58
Q

Crossing Over

A

during Prophase I of meiosis, homologous chromosomes come together in a process called synapsis

each synaptic pair contains four chromatids called a tetrad; these break at the chiasma

DNA is exchanged via crossing over

NOTE: this happens between HOMOLOGOUS CHROMOSOMES and not between sister chromatids

59
Q

Linked Genes and recombination via crossing over

A

Linkage refers to the tendency of genes to be inherited together

genes that are farther away are less likely to be linked and more likely to undergo crossing over relative to each other

60
Q

Ploidy through Mitosis vs Meiosis

note: n = 23

A

Mitosis: 2n –> 2x 2n

Meiosis: 2n –> 2x n (Meiosis I; split homologous pairs) –> 4x n (Meiosis II)

61
Q

What is the SRY gene?

A

The SRY (sex-determining region Y) is a gene on the Y chromosome which encodes for transcription factors that initiates testis differentiation

62
Q

Sertoli cells

A

essential for spermatogenesis

nourish the formed sperm cells in the seminiferous tubules

63
Q

Leydig cells

A

secrete testosterone and other androgens

64
Q

Acrosome

A

cap on the head of a sperm

derived from the golgi apparatus and is necessary to penetrate the ovum

65
Q

Primary Oocytes

A

the oogonia that have already undergone DNA replication at birth

2n cells arrested in Prophase I

after menarche, one will complete meiosis I each month and produce a secondary oocyte (n) and polar body

66
Q

Secondary Oocyte

A

arrested in Metaphase II (n)

will only complete the remainder of meiosis II if fertilized by a sperm cell

67
Q

Describe hormonal control prior to and during puberty in a female/

A

Before puberty: the hypothalamus restricts the production of GnRH (gonadotrophin-releasing hormone)

Puberty: hypothalamus produces GnRH, which triggers the anterior pituitary gland to release FSH (follicle-stimulating hormone) and LH (luteinizing hormone)

68
Q

Hormonal control of male sexual development

A

FSH stimulates Sertoli cells and triggers sperm maturation and LH causes the interstitial cells to produce testosterone

testosterone results in the development of secondary sex characteristics

69
Q

Hormones and the menstrual cycle

A

Estrogen is secreted in response to FSH and results in the development and maintenance of the female reproductive system; leads to thickening of the endometrium

Progesterone is secreted by the corpus luteum (remains of ovarian follicle after ovulation) in response to LH; development and maintenance of the endometrium

70
Q

Follicular Phase of Menstrual Cycle

A

begins with the menstrual flow

GnRH increases due to estrogen and progesterone drop off; this leads to increased FSH and LH

these develop ovarian follicles which begin to produce estrogen and negative feedback inhibit GnRH, FSH, and LH

71
Q

Ovulatory Phase of the Menstrual Cycle

A

Estrogen reaches a point where it positive feedback on GnRH, FSH, and LH

the spike in LH induces ovulation

72
Q

Luteal Phase of Menstrual Cycle

A

LH causes follicle to form corpus luteum which secretes progesterone

progesterone and estrogen both high and inhibit GnRH, LH, and FSH

73
Q

Blastulation

A

First phase of development

solid mass of cells called a morula and then the blastula which implants in the endometrium

74
Q

Gastrulation

A

occurs after blastulation

generation of three distinct cell layers

archenteron (membrane invagination) and blastopore (opening of archenteron…turns into anus)

75
Q

Primary Germ Layers

A

Ectoderm
- outermost; integument and nervous system

Mesoderm
- middle layer; muscular and connective tissue, circulatory

Endoderm
- epithelial lining of digestive and respiratory

76
Q

Neurulation

A

development of the nervous system

notochord (mesoderm) induces neural folds (ectoderm) and neural crest cells

77
Q

Neurulation

A

development of the nervous system

notochord (mesoderm) induces neural folds (ectoderm) and neural crest cells

78
Q

Kinesin vs Dynein direction

A

Kinesin = ANTEROGRADE movement on microtubule
Dynein = RETROGRADE movement on microtubule

79
Q

What is the role of fallopian cilia?

A

they PROPEL the fertilized oocyte forward into the uterus for proper implantation

MCAT (6 decks)

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