Prelim Unit Two Flashcards Preview

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Flashcards in Prelim Unit Two Deck (35)
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1

Stem cells

Unspecialised cells
Used for growth and repair
Come from embryo

2

Mitosis

pairs of chromatids become visible
Line up at equator
Pulled apart by spindle fiber to form two new nuclei
Cytoplasm spilts to form two daughter cells

3

Specialised cells

Sperm
Red blood cell
Muscle cell

4

Parts of NS

Brain CNS
Spinal cord CNS
Nerves

5

NS made up of

Neurons

6

Parts of brain

Cerebrum
Cerebellum
Medulla

7

Cerebrum

Responsible for thoughts consciousness reasoning and emotions

8

Cerebellum

Balance and coordination

9

Medulla

Breathing and heart rate

10

Receptors

Generate electrical impulses in response to stimuli

11

Electrical impulses

Carry messages along sensory neurons in the CNS
In inter neurons carry messages to motor neurons

12

Motor neurons

Electrical impulses carry messages to effectors and brings response

13

Synapse

Narrow gap between neurons
Chemicals released into it to allow electrical impulse to be generated in next neuron

14

Reflex

Protect the body from harm
Rapid actions that don’t require processing from brain

15

Reflex arc

The group of neurons involved with the structure and function of a reflex

16

Gametes

Sex cells
Haploid
Either make or female

17

Flowers

MALE GAMETES
inside pollen grains and made in anthers
FEMALE GAMETES
inside ovules and made in ovaries

18

Humans

MALE GAMETES
sperm cells produced in testes
Sperm very small can swim
FEMALE GAMETES
egg cells produced in ovaries
Larger and have food supply

19

Fertilisation

Fusion of two haploid nucleis to form diploid zygote that divides to become embryo

20

Haploid

Single set of chromosomes

21

Diploid

Double set of chromosomes

22

Zygote

Fertilised egg

23

Variation

Differences in species
Combining two genes from two parents adds to variation

24

Discrete variation

Clear cut difference
Shows discontinuous pattern
Involves single gene inheritance

25

Polygenic

Different alleles of different genes involved
Continuous variation

26

Polygenic inheritance

Shows variation of values between minimum and a maximum

27

Phenotype

Outward appearances of characteristic

28

Genotype

Symbols of phenotype

29

Recessive

Allele of gene that only shows in phenotype if it’s homozygous

30

Alleles

Type of gene