Brainscape's Knowledge GenomeTM

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


See full index

Biology 1 > Module 5 > Flashcards

Module 5 Flashcards

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

Why is sexual reproduction important?

A
  • produces offspring that are genetically different to their parents
  • generates variation within population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is sexual reproduction expensive for animals?

A
  • production of gametes
  • production of pheromones
  • cost of finding a mate
  • competition b/w males
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

sex determination

A
  • embryonic gonads form that could either become testes or ovaries
  • the presence or absence of SRY gene decides which developmental pathway is followed
  • this gene codes for TDF (a gene regulation protein)
  • by binding to specific DNA sites, TDF stimulates the expression of genes for testis development
  • found on Y chromosome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The gonads (testes & ovaries) produce which 3 major steroid sex hormones?

A
  • androgens (principally testosterone)
  • oestrogens (principally oestradiol)
  • progesterone
  • cholesterol is their precursor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

primary sex characteristics

A

reproductive structures that develop in the embryo
- penis, testes, seminal vesicles, associated ducts
- ovaries, fallopian tubes uterus, vagina
- brain sex

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

ovaries

A

eggs mature in & are released by the ovaries (produces eggs, estrogen, & progesterone)

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

oviducts

A

collects eggs at ovulation, provides a site for fertilization then moves the embryo to the uterus

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

uterus

A

provides protection, food, oxygen and removal of waste products for the fetus during pregnancy
- blastocyst implants in the ENDOMETRIUM of the uterus

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

cervix

A

neck of the uterus which protects the fetus during pregnancy and then dilates to provide a birth canal

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

vagina

A

stimulates penis to cause ejaculation & provides a birth canal

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

What is folliculogenesis

A

development of the follicle (follicle includes egg, fluid accumulation, theca cells, granulosa cells)

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

Oogenesis

A
  1. mitosis - oogonium
  2. growth –> primary oocytes
  3. primary oocyte & its surrounding cells = follicle
  4. meiosis I - stops at prophase I –> primary follicle
  5. at menstrual cycle, meiosis I is finished –> large secondary oocyte + unequal division of cytoplasm (2 haploid nuclei)
  6. meiosis II –> stops in prophase II
  7. ovulation = follicle ruptures, releasing oocyte
  8. the remaining follicle cells form the corpus luteum, which produces progesterone + estrogen
  9. after FERTILIZATION, secondary oocyte completes 2nd division of meiosis to form an ovum (one set of chromosomes - haploid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

estrogen

A
  • produces by granulosa cells in follicle
  • acts via estrogen receptors
  • regulates oviduct (Fallopian tube), uterus, cervix, vagina, & other sex organs
  • prepares endometrium for implantation (increases vascularization, blood supply)
  • promotes oestrus (or mating) behaviour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

progesterone

A
  • produced by corpus luteum
  • acts via progesterone receptors
  • regulates oviduct, uterus, cervix, vagina, & other sex hormones
  • prepares endometrium for implanation
  • modulates effects of estrogen, STOPS follicle growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Menstruation

A
  • elimination of the thickened lining of the uterus (endometrium) from the body via the vagina
  • menstrual fluid: consists of blood, lining of the uterus, & uterine mucus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Hypothalamo-pituitary-gonadal axis (HPG axis)

A
  • hypothalamus secretes gonadotropin releasing hormone (GnRH) that acts on anterior pituitary
  • GnRH release is in pulses
  • anterior pituitary produces gonadotrophins (FSHH & LH)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

LH - luteinizing hormone

A
  • stimulates theca cells to produce androgens
  • a surge in LH stimulates ovulation
  • stimulates formation of corpus luteum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are theca cells?

A

Theca cells are a group of endocrine cells in the ovary made up of connective tissue surrounding the follicle. They have many diverse functions, including promoting folliculogenesis and recruitment of a single follicle during ovulation.

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

FSH - follicle stimulating hormone

A
  • stimulates folliculogenesis
  • acts on granulosa cells to stimulate the conversion of androgens to estrogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are granulosa cells?

A

Granulosa cells are a type of cell in your ovaries that produce hormones including estrogen and progesterone. Hormones released from the base of your brain (anterior pituitary) control the numbers and function of granulosa cells

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

When is the follicular phase?

A

days 1 - 14 (maturation of follicle)

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

when is the luteal phase?

A

days 14 - 28 (preparation for implantation)

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

What is endometriosis?

A
  • affects 10% of women
  • endometrial cells grow in other PARTS of body (eg around ovaries, bladder, rectum)
  • severe abdominal pain & infertility
  • endometrial cells have estrogen & progesterone receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What will happen to this endometrial tissue (outside endometrium) during the menstrual cycle?

A
  • In response to hormones in the menstrual cycle the endometrial cells outside the uterus GROW in response to progesterone
  • Shed into the pelvic cavity when the progesterone levels drop
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Stages of menstrual cycle from day 1

A
  1. menstruation
  2. follicular phase
  3. ovulation
  4. luteal phase
26
Q

where is sperm produced?

A

in the seminiferous tubules in the testis

27
Q

Where is sperm stored?

A

in the epididymis

28
Q

Van deferens

A

transports sperm from epididymis to urethra (via ejaculatory ducts)

29
Q

seminiferous tubules

A

sperm with flagella are released in the lumen of the seminiferous tubules
occurs from outside to inside

30
Q

testis

A
  1. sperm production –> controlled by Sertoli cells which convert testosterone to oestradiol to facilitate spermatogenesis
  2. hormone production –> testosterone is produced in Leydig cells (interstitial space in bw tubules) – steroid, androgen
31
Q

How is testosterone produced?

A
  • produced by Leydig cells
  • steroid hormone
  • acts via androgen receptor in cells
  • can be converted to oestradiol in Sertoli cells to aid spermatogenesis
  • modulates secondary sex characteristics in males
32
Q

urethra

A

transfers semen during ejaculation & urine during urination

33
Q

scrotum

A

holds testes at lower than core body temp

34
Q

prostate gland

A

secretes alkaline fluid that is added to sperm at the start of ejaculation & helps sperm to swim

35
Q

seminal vesicle

A

secretes an alkaline fluid at the end of ejaculation containing proteins that make the semen sticky

36
Q

structure of mature sperm

A

specialized for motility w/ 3 parts

  1. head - acrosome containing enzymes to digest the eggs’ outer coating
  2. mid-piece - lots of mitochondria to power the journey through female reproductive tract
  3. tail (flagella) – 9+2 microtubule arrangement
37
Q

stages in spermatogenesis

A
  1. outer layer called germinal epithelium cells (2n) divide by mitosis (spermatogonia)
  2. diploid cells grow –> primary spermatocytes
  3. 1st division of meiosis –> secondary spermatocytes (n)
  4. 2nd division of meiosis –> 2 spermatids (n)
  5. spermatids become associated w Sertoli cells which help spermatids –> spermatozoa (CELL DIFFERENTIATION)
  6. sperm detach from Sertoli cells & carried out of testis by fluid in center of seminiferous tubule
38
Q

Which factors affect quality of male sperm?

A
  • diet
  • smoking
  • drugs
  • BMI
  • alcohol consumption
  • exposure to heat
  • acute viral illness
39
Q

HPG axis in males

A
  • GnRH from hypothalamus stimulates release of LH + FSH from anterior pituitary
  • LH stimulates Leydig cells to produce testosterone
  • FSH stimulates spermatogenesis by acting on Sertoli cells
  • testosterone affects accessory sex organs & secondary sex characteristics
  • NEGATIVE FEEDBACK regulates testosterone + spermatogenesis

testosterone INHIBITS GnRH & LH secretion
inhibin produced by Sertoli cells INHIBITS FSH secretion

40
Q

Which hormone is produced from fertilization?

A

hCG
stimulates corpus luteum to continue producing progesterone + estrogen
pregnancy kits detect hCG

41
Q

contraceptive methods

A
  • physical barriers (condoms, diaphragm, etc.)
  • chemical (oral contraceptive pill, contraceptive implants)
42
Q

How does the oral contraceptive pill work?

A
  • combined oral contraceptive contains synthetic progesterone + estrogen
  • works by suppressing GnRH, FSH, & LH
  • prevents follicle growth & ovulation
  • increases cervical mucus thickness to stop sperm
  • continual exposure to progesterone & estrogen THINGS endometrial lining, hampers implantation
43
Q

which endocrine disruptors can affect reproductive organs?

A
  • hormonally active synthetic chemicals
  • plastics, pesticides, phthalates
44
Q

Bisphenol A (BPA)

A
  • is a monomer
  • leaches from plastics when heated, or they age, or treated w/ acid & base
  • oestrogen mimics, binds to estrogen receptors
45
Q

Key features of exchange surfaces

A
  • large surface area relative to volume
  • very thin barrier
  • concentration gradient
  • selectively permeable
46
Q

Fick’s law

A

rate of diffusion = (SA x partial pressure gradient x diffusion coefficient)/diffusion distance

47
Q

why is air a better respiratory medium than water?

A

water is much denser than air so much more energy is needed to move water around
O2 has low solubility in water; CO2 had higher partial pressure in water

48
Q

factors that reduce O2 solubility in water

A
  • temp
  • salinity
  • pressure
  • organisms living in water
49
Q

gas exchange system in insects

A

have tracheae (air passages that extend throughout insect body)

50
Q

gas exchange system in crabs

A

have internal gills (open circulatory system)

51
Q

gas exchange in fish

A

have internal gills (closed circulatory system)
= lamella on gill filaments increase SA

52
Q

Explain why countercurrent flow is better than concurrent flow in fish

A

countercurrent flow: as blood flow in the opposite direction to the water, it always flows next to water that has given up less of its oxygen (so more oxygen can enter the blood)

so exchange is more complete

53
Q

what is tidal volume

A

the normal amount of air exchanged when breathing at REST

54
Q

Most CO2 in blood is carried as . . .

A

bicarbonate ions
To minimize changes in pH of blood, hemoglobin can bind to CO2 & act as a buffer

55
Q

What i the Haldane effect?

A

Increased capacity of blood to carry CO2 when at low oxygen saturation

Properties of hemoglobin that make the removal of CO2 more likely:
- CO2 binds to hemoglobin
- Hemoglobin not carrying O2 (deoxygenated) has a higher affinity for CO2
- The Haldane effect facilitates removal of CO2 at tissues w/ low partial pressure of O2
- Bohr & Haldane effects are results of same phenomena

56
Q

myoglobin

A

muscles have their own oxygen storing molecule called myoglobin

Binds ONE oxygen per myoglobin
Increased O2 affinity compared to haemoglobin
Binds oxygen at lower partial pressure (concentration)
Oxygen dissociation curve is to the LEFT of hemoglobin

57
Q

Respiratory adaptations

A

How do marine mammals hold their breath for so long during underwater dives?
Increased concentration of hemoglobin
Increased concentration of myoglobin (10x more than in humans)
Reduce their heart rate
Reduce blood flow to extremities & organs

58
Q

How does COVID-19 affect respiratory system?

A
  • Virus enters lungs
  • Virus binds to alveolar wall cells, injects its DNA
  • Infected cell produced many copies of virus
  • Alveolar cell destroyed, virus particles released & infected neighboring cells
59
Q

What chemoreceptors? how are they involved in cell communication & breathing?

A
  • found on surface of medulla & are sensitive to the P(CO2) & pH of cerebrospinal fluid
  • also found on large vessels leaving the heart & are sensitive to decreased O2 availability
60
Q

A shift to the right (of dissociation curve)

A

Bohr effect
High CO2
increased acidity
BPG

Biology 1 (10 decks)

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