Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > Reproduction And Inheritance > Flashcards

Reproduction And Inheritance Flashcards

(75 cards)

Start Studying
1
Q

Define Diploid Cells:

A
  • Two copies of each chromosome arranged in pairs

* Diploid number of human cell nucleus is 46 chromosomes

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

Define Haploid Cells:

A

•Single chromosome in a cell (23)

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

Describe the structure of DNA:

A
  • Double helix structure of two strands made up of sugar phosphate backbone
  • Held together by bases which are paired
  • Adenine pairs with Thymine and Cytosine pairs with Guanine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the function of tRNA in translation?

A
  • Transports amino acids in ribosome

* Has anticodon which is complementary to codon on mRNA

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

What is a codon?

A
  • Each amino acid is coded for by a sequence of three bases in the gene
  • E.g. ACA or CTG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How are Proteins made?

A
  • Made up of chains of amino acids
  • Each protein has a different number and order of amino acids
  • Each protein can have a different function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define a gene:

A
  • A section of DNA that codes for a particular protein

* Each gene contains different sequence of bases

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

Define Chromosomes:

A

Long strings of DNA

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

What is Protein Synthesis?

A
  • Nucleus contains chromosomes
  • DNA in nucleus is too big to leave nucleus
  • Polymerase separates DNA into 2 strands
  • Transcription makes a mRNA of the DNA strand
  • mRNA has swapped the base of thymine with uracil
  • mRNA is now small enough to leave the nucleus
  • mRNA floats out to the cytoplasm, joins with an organelle called ribosome
  • Amino Acids to ribosome by tRNA
  • Translation is reading mRNA, creating corresponding protein via tRNA
  • Amino Acids joined together - amino acid chain so now a protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define Mitosis:

A
  • A cell reproduces itself by splitting to form two cells with identical sets of chromosomes
  • Asexual reproduction
  • Produces genetically identical cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define Asexual reproduction:

A
  • Involves one parent

* Offspring have identical genes to parent

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

What is the function of Mitosis?

A
  • Grow and repair damaged cells

* Asexual reproduction

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

Define Sexual Reproduction:

A
  • Fusion of male and female gametes

* Two parent cells, offspring contain mixture of their parent genes

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

Define Meiosis:

A
  • Type of Cell division
  • Produces 4 haploid cells
  • Chromosomes not identical
  • Only happens in reproductive organs (ovaries and testes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are causes of variation?

A
  • Mitosis In sexual reproduction

* Environmental effects

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

How many genes control the majority of characteristics?

A

2

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

What are differences between Mitosis and Meiosis?

A
  • Cell division in Meiosis but only 1 in Mitosis
  • Mitosis takes place throughout body, Meiosis only occurs in reproductive organs (ovaries and testes)
  • Mitosis creates daughter cells with identical DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define Pollination:

A

Transfer of pollen from an anther to a stigma so male gametes can fertilise the female gametes in sexual reproduction

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

Define Cross Pollination:

A
  • Type of sexual reproduction where pollen is transferred from the anther of one plant to stigma of another
  • Plants rely on insects or wind to help cross pollinate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How are Plants adapted for Insect Pollination?

A
  • Large bright petals - attract insects
  • Scented flowers and nectaries - attract insects
  • Enclosed stamen
  • Sticky stigma - pollen will stick to it
  • Big sticky pollen grains - grain stick to insect as going from plant to plant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How are Plants adapted for Wind Pollination?

A
  • Small dull petals
  • No nectaries or strong scent
  • Many small and light pollen grains - easily carried by wind
  • Stamen exposes
  • Large feathery stigma - catch pollen from wind
  • Long filament that hangs out of flower - a lot of pollen gets blown away by wind
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the Stamen (Male Reproductive Part) of the flower:

A
  • Stamen is anther & filament
  • Anther contains pollen grains - produce male gametes (sperm)
  • Filament is the stalk that supports anther
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the Carpel (Female Reproductive Part) of the flower:

A
  • Carpel is ovary, style & stigma
  • Stigma is end but that pollen grains attach to
  • Style is rod-like section that supports stigma
  • Ovary contains female gametes (egg) inside ovules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is a seed formed?

A
  • Pollen lands on stigma
  • Pollen tube grows to ovary
  • Nucleus travels into ovule
  • Nucleus fertilises ovum
  • Fertilisation is two nuclei fusing together to make a zygote
  • Divide by Mitosis to form embryo
  • Seed is formed
  • Fruit is formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are the conditions for germination to occur?
* Moisture- Solution for enzymes to function * Oxygen - Respiration * Warmth - Speed up chemical reactions
26
How can you investigate the conditions needed for germination?
* Take 4 boiling tubes with Cotten wool at bottom with seeds on top * Tube 1 - H2O, O2, room temp * Tube 2 - O2, room temp * Tube 3 - H20, O2, low temp * Tube 4 - H20, room temp * Leave for few days & observe * Germination only in Tube 1 - all conditions were present
27
How do Plants reproduce asexually using the natural method of Runners?
* Plant sends out runners - fast growing stems that grow out sideways, above ground * Runners take root at various points and new plants grow * New Plants are clones of parent plant * No genetic variation between them
28
How do Plants reproduce asexually using the artificial method of Cuttings?
* Take cuttings from good parent Plants, plant them to produce genetically identical copies (clones) of parent plant * Cuttings kept in moist conditions * Plants can be produced quickly and cheaply
29
What is the function of Testes?
Produce sperm
30
What is the function of Prostate Gland?
Release fluid to form semen
31
What is the function of Urethra?
Transport semen out of the body
32
What is the function of the Penis?
Sexual intercourse
33
What is the function of the Sperm Duct (Vas Deferens)?
Carries sperm from testes towards urethra
34
What is the function of the Uterus?
* Embryo grows | * Foetus develops
35
What is the function of the Vagina?
Sexual intercourse
36
What is the function of the Ovary?
* Produce sex Hormones | * Produce eggs
37
What is the function of the Oviduct?
* Fertilisation takes place | * Carries ovum from ovary to uterus
38
What does Oestrogen in women cause?
* Hair underarms and pubic area * Hips to widen * Development of breasts * Ovum release and start of periods
39
What does Testosterone in men cause?
* Hair on face and body * Muscles to develop * Penis and testicles to enlarge * Sperm production * Deepening is voice
40
Describe the Menstrual Cycle:
* Day 1 = Menstruation starts, uterus lining breaks down * Day 4-14 = Uterus lining builds up into think spongy layer ready to receive a fertilised egg * Day 14 = Egg develops and is released from ovary - ovulation * Day 14-28 = The wall is maintained, if no egg landed on uterus wall, spongy lining break down and cycle starts again
41
What Hormones is the Menstrual Cycle controlled by?
* FSH * Oestrogen * LH * Progrsterone
42
What is the hormone FSH?
* Produced In Pituitary Gland * Causes egg to mature in a follicle structure * Stimulates ovaries to produce Oestrogen * Oestrogen inhibits the release of FSH
43
What is the hormone Oestrogen?
* Produced In Ovaries * Causes uterus lining to grow * Stimulates release of LH
44
What is the hormone LH?
* Produced In Pituitary Gland | * Stimulates release of egg at day 14 - ovulation
45
What is the hormone Progesterone?
* Produced In Ovaries by remains of follicle after ovulation * Maintains uterus lining of 2nd half of cycle * When levels of progesterone fall, lining breaks down * Inhibits release of LH and FSH
46
What is an Allele?
Different versions of the same gene
47
What is a Genotype?
The alleles that you have
48
What is a Phenotype?
The characteristics the alleles produce
49
What are the Dominant Alleles show by?
A capital letter
50
What are the Recessive Alleles show by?
A small letter
51
What does it mean if you are Homozygous?
* For a trait you have 2 alleles the same for that particular gene * E.g. CC or cc
52
What does it mean if you are Heterozygous?
* For a trait you have 2 different alleles for that particular gene * E.g. Cc
53
What is meant by Codominant?
2 alleles are equally expressed
54
What is the probability of having a daughter if you already had two sons? Explain your answer:
* 50% | * Male has equal chance of producing X (female) or Y (male) in Chromosomes in gamete
55
A black mouse is bred with a brown mouse. All offspring have black fur. Which allele is dominant?
Black
56
What letters represents the Male Chromosomes?
XY
57
What letters represent the Female Chromosomes?
XX
58
How is the baby protected from bumps and shocks?
Amniotic Fluid
59
Which factors aren’t affected by environment and are only genetic?
* Eye colour * Hair colour * Inherited disordered * Blood group
60
How does a mother’s diet affect the baby?
•Affect baby’s weight
61
How is Health affected by genes and environment?
* Some people more likely to get certain diseases cause in their genes (cancer,etc) * However, if you smoke or only eat junk food it can lead to diseases too
62
How is Intelligence affected by genes and environment?
* Maximum IQ determined by genes | * Also, determined by school life and upbringing
63
How is Sporting Ability affected by genes and environment?
* Genes determines your potential | * Also, training is important
64
What are Plants affected by in the Environment?
* Sunlight * Moisture level * Temperature * Mineral content of soil
65
What is the Theory Of Evolution?
Life began as simple organisms from which more complex organisms evolved
66
What is Polygenes?
* Most characteristics are coded for by more than 1 gene | * Height, intelligence, body type
67
What was Darwin’s Theory of Evolution?
* Presence of natural variation (in population of organisms) * Competition for limited resources * Survival of the fittest * Inheritance of successful adaptions * Extinction of species unable to compete
68
What is an example of natural selection to do with bacteria?
Over time, bacteria can become resistant to certain antibiotics
69
What is Transgenics?
Foreign DNA, including DNA from humans, can be inserted into animals
70
What are Mutations?
* Changes to a genetic code * Rare * Change sequence of DNA base, produces genetic variant, sometimes changes the protein that it codes for
71
What could a Mutation in gene that Codes for an Enzyme lead to?
* Change in shape of an enzymes active site | * Altering it’s function
72
What do Most Mutations have no effect on?
* Recessive allele | * Phenotype - they’re neutral
73
What does Mutations have an effect on very rarely?
* Significant effect on phenotype * Result in different protein that can no longer carry out its function * Harmful - cancer
74
How is a chance of Mutation Increased?
* Ionising radiation = X-rays, gamma rays, UV rays | * Chemicals - Mutagens = chemicals in tobacco
75
What does is mean if Bacteria is Antibiotic Resistance?
* In large population of bacteria, some aren’t affected by antibiotic - due to mutation * They survive and reproduce, creating more bacteria that are not affected by antibiotic

Biology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions