Short Questions Flashcards
Serum
plasma-clotting proteins
Plasma
liquid part of blood
2 Plasma proteins
antibodies
clotting proteins
Where are red blood cells produced?
Bone marrow
Fate of red blood cell
Iron from haemoglobin stored in liver and recycled to make new haemoglobin
Converted to bile pigments
Where are platelets produced?
Bone marrow
Function of platelets
clot blood
Functions of blood clots
reduce blood closs
prevent entry of micro-organisms
Functions of blood
Transport food,waste products and hormones
Transport oxygen and heat
Defend against disease
Blood groups
A
B
AB
O
Why do red blood cells have a biconcave shape?
Larger surface area to exchange oxygen
Oxyhaemoglobin formation
haemoglobin+oxygen in lungs
Lymphocytes
stored in lymphatic system 25% 3 months-10 years Large,round nucleus Make antibodies
Monocytes
5%
6-9 days
Kidney shaped nuclei
Surround and digest bacteria (phagocytes)
Red blood cells
Transport oxygen
no nuclei
biconcave shape
Open circulatory system
blood leaves blood vessels and flows around cells before re-entering blood vessels again
Closed circulatory system
blood remains in a continuous system of blood vessels
Layers of arteries/veins
Outer layer:inelastic protein (collagen)
Middle layer:muscle and elastic fibres-alter size
Inner layer:endothelium
Lumen
Blood pressure
force the blood exerts against the wall of a blood vessel
Pulse
alternate contraction and expansion of arteries
Valves
control direction and prevent back flow
Characteristics of arteries
High pressure Away Thick wall Small lumen Pulses No valves High in oxygen (except pulmonary)
Characteristics of veins
Low pressure Valves Large lumen No pulses Low oxygen (excedpt pulmonary)
Pulmonary circuit
heart-lungs-heart
blood gains oxygen and loses co2 in lungs
Systemic circuit
heart-body-heart
blood loses oxygen and gains co2
portal system
blood pathway that begins and ends in capillaries
diastole
chambers relax
systole
chambers contract
Functions of the lymphatic system
defend against infection
collect tissue fluid and return it to blood
destroy microbes
absorb and transport fats
How does lymph differ from blood?
no red cells,platelets or large proteins
How does lymph move in blood vessels?
Muscles
General body movements
Where does lymph return to the blood?
subclavian vein
What are lymph nodes?
swellings along lymph vessels
filter bacteria
What does lymph consist of?
white blood cells,protein and fats
4 events in human nutrition
ingestion:taking in of food
Digestion:breakdown
Absorption:digested food passes into blood
Egestion:removal of unabsorbed waste
Incisors
cut and slice
Canines
grip and tear
premolars/molars
crush and grind
Dental formula
2(I2/2 C1/1 P2/2 M3/3 )
Epiglottis
Closes over trachea and ensures food passes down oesophagus
Oesophagus
carries food to stomach by peristalsis
Peristalsis
wave of muscular action in the walls of the alimentary canal that moves contents along
Stomach
muscular bag that holds and digests food
Mucus
Pepsinogen
Hydrochloric acid
Mucus
prevents self-digestion
Hydrochloric acid
activates pepsinogen
denatures salivary amylase
kills bacteria
loosens fibrous foods
Functions of the liver
making bile detoxifying e.g. alcohol deamination glucose to glycogen for storage storing vitamins and minerals
Functions of bile
emulsify lipids
neutralise chyme
excrete pigments
function of duodenum
digestion
function of ileum
absorption
What is present in pancreas for neutralising chyme?
sodium hydrogen carbonate
Adaptations of villi for absorption
large numbers (surface area) Walls one cell thick
Adaptations of small intestine for absorption
rich blood suply
lymph supply
numerous villi and microvilli (surface area)
Absorption of fats
lacteal-lymph
fatty acids and glycerol absorbed
re-form into fats and coated with protein and pass into lymph
transported to blood stream and absorbed
Absorption of other nutrients e.g. amino acids
absorbed by capillaries,carried to hepatic portal vein to liver
warehouse
amino acids-deaminated
Caecum and appendix
vestigial organs (lost their former use)
vestigial organs
lost their former use
Colon
reabsorbs water
Functions of symbiotic bacteria
B and K vitamins
Prevent growth of bacteria
Balanced diet
contains all necessary food types in correct proportions
Pharynx
throat
larynx
voice box
Functions of nose
filter,moisten and warm air
Mucus in breathing system
sticky and traps small particles e.g. dust
Cilia
beat and create upward current,moving mucus upwards
Pleura
membranes
Pleural cavity
Contains liquid which reduces friction during breathing
Function of alveoli
gas exchange
Adaptations of alveoli for gas exchange
huge surface area
thin walled
moist
network of capillaries
How is oxygen transported?
oxyhaemoglobin
How is co2 transported?
Blood plasma
Gas exchange-co2 and water
pass out of body cells by diffusiom
diffuse from blood plasma into alveoli
Gas exchange-oxygen
passes from alveoli into blood
into body cells
Inhalation
brain controls active ribs up and out diaphragm down volume increases pressure decreases external air pressure higher-air forced in
Exhalation
intercostal muscles and diaphragm relax passive ribs down and in diaphragm up volume decreases pressure increases air forced out
Symptoms of asthma
noisy,breathlessness
Causes of asthma
allergens e.g. pollen
bronchioles inflamed and narrow
Prevention of asthma
avoid allergens
Treatment of asthma
bronchodilators/steroids
What part of the brain controls breathing?
medulla oblongata
How does co2 control breathing?
carbonic acid causes ph to drop
impulses to diaphragm and intercostal muscles-breathe
excercise-co2 increases
High co2
faster breathing
Low co2
slower breathing
Pathogen
organism that causes disease
Immunity
ability to resist infection
general defence system
barrier to all pathogens attempting to gain entry (non specific)
Specific defence system
attacks particular pathogens
Lysozyme
enzyme found in sweat and tears
attacks and dissolves cell walls of bacteria
Skin
structural barrier
clotting
prevents entry of further pathogens
sebaceous glands
sebum (chemicals that kill bacteria)
Second line of general defence
Phagocytes:surround and ingest pathogens
Defence proteins:complement,interferons
Inflammation:more WBC to area
Interferons
prevent viral multiplication
limit spread of viruses
Antigen
foreign molecules that stimulate production of antibodies
Antibody
protein produced by WBC in response to a specific antigen
How do lymphocytes fight infection?
attack body cells that display antigens
produce antibodies
Antigen-antibody reaction
highly specific
precise fit
each antigen stimulates the production of only one specific antibody
Induced immunity
ability to resist disease caused by specific pathogens by producing antibodies
active immunity
production of a person’s own antibodies in response to foreign antigens
natural active immunity
pathogen enters body in normal way
Artificial active immunity
pathogen medically introduced
Vaccine
non disease causing dose of a pathogen which triggers
production of antibodies
Passive immunity
given antibodies formed by another organism
natural passive immunity
child gets antibodies from mother
artificial passive immunity
given an injection containing anitbodies made by another organism
Vaccination
administration of a non-disease causing dose of a pathogen to stimulate the production of antibodies
immunisation
produce/injected with antibodies against a pathogen
Where do B cells mature
Bone marrow
Where do T cells mature
thymus gland
Plasma B cells
produce antibodies
Memory B cells
survive for years after the infection is eliminated and can make the specific antibody if the same infection later enters the body
T cells
helper T
killer T
suppressor T
memory T
Helper T
stimulate B and killer T
Killer T
perforin
destroy abnormal body cells
Suppressor T
inhibit immune response
Memory T
survive for years after infection eliminated and can stimulate specific B and killer T if same infection later enters the body
Gonad
sex organ that produces sex cells
Testes
male gonads
temp maintained at 35 degrees (meiosis)
produce sperm
Epididymis
sperm mature
Sperm duct
carries sperm to urethra
urethra
carries urine/sperm out of the body
semen
fluid containing sperm and seminal fluid
seminal fluid
medium for sperm to swim in and nourishes
What 3 parts produce seminal fluid?
seminal vesicles
prostate gland
cowper’s gland
What form of nuclear division are sperm formed by?
meiosis
acrosome
enzyme that digests egg membrane
midpiece
mitochondria
tail
allows the sperm to swim
puberty
beginning of sexual maturity
infertility
inability to produce offspring
secondary sexual characteristics
features that distinguish males from females apart from the sex organs
Hormones in male reproductive system
FSH causes sperm producing cells to divide by meiosis-haploid sperm
LH causes testes to produce testosterone
Examples of male secondary characteristics
pubic hair
enlargement of larynx
widening of shoulders
growth spurt
Example of male infertility
low sperm count
cause of low sperm count
smoking
alcohol
steroids
corrective measures for low sperm count
changes in diet and lifestyle
stop smoking,alcohol,drugs
ovulation
release of egg from ovary
Graafian follicle
produces oestrogen
Funnels in fallopian tube
catch egg after ovulation
How is egg moved along fallopian tube?
cilia and peristalsis
Vagina
allows entry of sperm and birth canal
menstrual cycle
series of events that occurs every 28 days on average in the female if fertilisation has not taken place
menopause
ovulation and menstruation stop
copulation
sexual intercourse
orgasm
physical and emotional sensations experienced at the peak of sexual excitement
ejaculation
release of semen from penis
insemination
release of semen into vagina,just outside of cervix
fertilisation
nucleus of sperm fuses with nucleus of egg,forming a diploid zygote
menstrual disorder
fibroids-benign tumours of the uterus
causes of fibroids
abnormal response to oestrogen
Days 1-5 of menstrual cycle
endometrium breaks down/shed (menstruation)
meiosis in ovary-new egg surrounded by graafian follicle
Days 6-14
oestrogen-causes endometrium to thicken
prevents new eggs
Day 14
ovulation-graafian follicle bursts to release egg
Days 14-28
corpus luteum progesterone-causes endometrium to thicken prevents new eggs corpus luteum degenerates around day 22 breakdown on day 28
menstruation
discharge of the lining of the uterus and the unfertilised egg
Secondary female characteristics
maturing of breasts
pubic hair
growth spurt
Female infertility example
endocrine gland failure
Cause of endocrine gland failure
pituitary gland fails to produce FSH and LH
Corrective measures of endocrine gland failure
hormone supplements
invitro
FSH
pituitary gland
1-5
stimulates few potential eggs
Oestrogen
Graafian follicle
5-14
causes endometrium to develop and inhibits FSH
No further eggs develop
LH
pituitary gland
day 14
causes ovulation and corpus luteum
Progesterone
corpus luteum 14-28 maintains endometrium inhibits FSH and LH no further eggs developed
Implantation
embedding of fertilised egg into lining of the uterus
survival of sperm
up to 7 days
survival of egg
up to 2 days
where does fertilisation take place
fallopian tube
When does implantation occur
6 to 9 days after fertilisation
amnion
secretes amniotic fluid,surrounds and protects embryo by acting as a shock absorber
In vitro
removing eggs from an ovary and fertilising them outside the body
when does the placenta start to function
4 weeks
functions of the placenta
exchange-gases,nutrients waste etc
prevents blood mixing
progesterone
why should blood of baby and mother not mix?
blood pressure
blood groups
morula
solid ball of cells formed from a zygote by mitosis
blastocyst
hollow ball of cells formed from a morula
germ layers
basic layers of cells in the blastocyst from which all adult tissues and organs will form
endoderm
inner lining of digestive,respiratory systems
mesoderm
muscles,skeleton
ectoderm
skin,nails,hair
week 4
heart forms
brain
umbilical cord
week 5
internal organs
limbs
week 6
eyes,mouth,nose,ears
week 8
human face,ovaries/testes
week 12
bone replaces cartilage
gestation
length of time spent in uterus from fertilisation to birth
Hormones associated with birth
placenta stops producing progesterone
uterus contracts
pituitary gland-oxytocin-stronger contractions and labour
Stages of birth
1-12 hours,contractions bush foetus towards cervix,waters break
2-20 minutes to an hour,cervix dilates,foetus pushed out through cervix and vagina,cord clamped
3-afterbirth-placenta
colostrum
thick yellow fluid provides protection against infection
Lactation
secretion of milk by the mammary glands of a female
Hormone in breastfeeding
prolactin stimulates milk production
Biological benefits of breastfeeding
nutrients antibodies sterile recovery breast cancer
birth control
limits taken to limit the no. of children born
contraception
deliberate prevention of fertilisation/pregnancy
Examples of contraception
Natural-cycle
Chemical-spermicides,the pill
Surgical-vasectomy,tubal ligation
Mechanical-condoms
Virus structure
protein coat (capsid) nucleic acid:RNA or DNA
Viruses : living
genetic material
protein coat
can replicate
Vruses :dead
non-cellular
cannot reproduce by themselves
No cell organelles
Only one type of nucleic acid
Shapes of viruses
round
rod
complex
bacteriophages
virus that infects bacteria
Stages in viral replication
attachment entry synthesis assembly release
attachment:virus
virus attaches to host cell
matches up with receptor sites
entry:virus
viral nucleic acid pushed through
protein coat stays outside
synthesis:virus
host nucleic acid made inactive
uses host organelles to produce new viral nucleic acid and proteins
assembly:virus
new viruses made inside host cell
release:virus
cell bursts to release between 100 and 100000 new viruses
retroviruses
protein coat
rna
enzyme
obligate parasite
can only replicate using a living cell
disadvantages of viruses
human disease e.g cold
plant disease eg tomato mosaic
animal disease e.g. rabies
benefits of viruses
genetic engineering-vectors
control of infections-bacteriophages
Functions of skeleton
support
movement
protection of organs
axial skeleton
vertebrae and skull
appendicular skeleton
limbs and girdles
Cranium
20 fused
vertebral column
cervical 7 thoracic 12 lumbar 5 sacrum 5 fused coccyx 4 fused
ribs
12 pais
1-7 true
8-10 false
11-12 floating
sternum
breast bone
pectoral girdle
shoulder
clavicle
collar bone
scapula
shoulder blade
arm
humerus,radius,ulna,carpals (8),metacarpals (5),phalanges
leg
femur,patella,tibia,fibula,tarsals(7),metatarsals(5)Phalanges
epiphysis
head/tail
diaphysis
shaft
periosteum
membrane that encloses
compact bone
strength and rigidity
composed of calcium salts and collagen
spongy bone
strength and rigidity
marrow
red marrow
produces red blood cells
yellow marrow
stores fat
converts to red
joint
place where 2 or more bones meet
3 types of joint
immovable e.g. skull
slightly moveable e.g.vertebrae
free moving e.g. hinge/ball and socket
synovial membrane
encloses joints and secretes synovial fluid
synovial fluid
lubricates and reduces friction
ligament
bone to bone
tendon
muscle to bone
antagonistic muscles
muscles that work in pairs opposite each other
one muscle contracts other relaxes
osteoblast
bone forming cell
produce collagen and calcium phosphate
osteoclast
break down bone
growth plate
area between epiphysis and diaphysis in a long bone in which bone growth occurs
Bone renewal
bone continuously broken down and replaced
bone material removed from interior and deposited on outside
osteoclasts remove worn cells and deposit calcium
What is bone renewal dependent on?
physical activity
diet
hormones
osteoarthritis
wear and tear of joints,degenerative joints wear faster than can be replaced pain and swelling reduce weight and correct footwear anti inflammatory meds and replacements
Deficiency in thyroxine
slow metabolism
overweight
treatment:hormone supplements and iodine
excess thyroxine
increased heart rate and blood pressure
weight loss
treatment:surgery
hormone supplements
insulin
HRT
Nerve Action v Hormone Action
H-chemical N-electrical
H-slow N-fast
H-long lasting N-brief
CNS
brain and spinal cord
Peripheral nervous system
nerve fibres that carry messages between CNS and rest of body
Ganglion
collection of cell bodies
Neuron
nerve cells that carry receptor messages
sensory neuron
carries impulses from sense organ to CNS
motor neuron
carries impulses from CNS to effector
Interneurons
carry impulses within CNS
Impulse
electrical movement using ions
Cell body
controls passage of impulses
produces neurotransmitter chemicals
axon
carry impulse to effector
dendrites
receive impulses and carry them toward cell body
schwann cells
produce myelin sheath
myelin sheath
protection/insulation
neurotransmitter swellings
release neurotransmitters that carry the impulse from one nerve to another
synapse
region where 2 neurons come into close contact
synaptic cleft
tiny gap between two neurons
benefits of synapse
allows transmit of impulse in one direction
impulses can be blocked by certain chemicals e.g. painkillers
cerebrum
voluntary actions e.g. thinking,language
cerebellum
muscular activity,balance
medulla oblongate
involuntary-breathing
hypothalamus
homeostasis and osmoregulation
pituitary gland
hormones
meninges
3 layers,protects
thalamus
sorting centre
dorsal root
carries nerve axons into spinal cord
ventral root
carries nerve axons away from spinal cord
central canal
contains ceberospinal fluid
reflex action
automatic,involuntary response to a stimulus
protect body from danger
reflex arc
pathway taken by a nerve impulse ina reflex action
Parkinsons disease
failure to produce dopamine
trembling,stiff
no prevention
physio,levodopa imitates dopamine
Iris
controls amount of light entering eye
Pupil
lets light into eye
aqueous humour
holds shape at front
vitreous humour
holds shape at back
lens
focuses light on the retina
retina
converts light impulses into nerve impulses
rods and cones
blind spot
no rods/cones
optic nerve leaves eye
optic nerve
carrys impulses to brain
cornea
lets light into eye
accomadation
ability of the eye to focus at different distances by altering shape
ciliary muscles
change shape of lens (accomodation)
Why are 2 eyes better than 1?
depth perception
3D vision
sclera
holds eye in shape
suspensory ligament
holds lens in place and changes its shape
pinna
collects sound
auditory canal
carries vibrations
eardrum
vibrates
ossicles
amplify vibrations
eusatchian tube
equalises air pressure on both sides
cochlea
hearing
semi circular canals
balance
3 planes
glue ear
surplus sticky fluid
grommets/nose drops
DNA structure
double helix
nucleotide:phosphate,sugar (deoxyribose) and base
Complementary base pairs
A+T (2 hydrogen bonds)
G+C (3 hydrogen bonds)
Purines
A and G
Pyridimines
C and T
DNA replication
double helix unwinds enzyme breaks bonds bases from cytoplasm enter nucleus bases attach to exposed complementary bases 2 exact replicas each new piece rewinds
RNA vs DNA
U,T
Single,double
RNA moves out of nucleus,DNA stays in
Ribose,deoxyribose
DNA profiling
process of making a unique pattern of DNA from one person that is compared with DNA of another person
DNA profiling process
dna released
cut into fragments using restriction enzymes
seperated by size using fel electrophoresis
smaller move further and faster
patterns compared
applications of DNA Profiling
criminal cases
paternity testing
genetic screening
identify presence/absence of altered/particular gene
Genetic engineering
artificial manipulation/alteration of genes
Allele
alternative forms of the same gene
autosome
chromosome that does not have role in determining sex
carrier
person who is heterozygous for a gene is said to be a carrier of the recessive gene
dihybrid
genetic croos involving two traits
diploid
2 copies of each chromosome,2 sets
dominant
prevents recessive allele from being expressed
gamete
haploid cell capable of fusion
gene
section of DNA that causes the production of a protein
Genetic expression
the way in which the genetic info in a gene is decoded and used to make protein
genetic code
sequence of bases that provide instructions to form a protein
heredity
passing on of traits,using genes,from one generation to the next
heterozygous
different alleles
homozygous
identical alleles
incomplete dominance
neither alleles masks the expression of the other
both equally expressed
linked genes
genes located on the same chromosome
locus
position of a gene on a chromosome
triplet/codon
sequence of 3 bases in DNA that act as a code for an amino acid
Test for reducing sugar
benedict’s solution
brick red
not present-blue
Test for protein
sodium hyrdoxide and dilute copper sulfate
present-violet
not-blue
population
all members of the same species living in an area
community
different populations in an area
climatic factor
weather over a long period of time
producers
organisms that carry out photosynthesis
consumers
take in food from another organism
decomposers
organisms that feed on dead organic matter
detritus feeders
organisms that feed on small pieces of dead organic matter
trophic level
feeding stage in a food chain
food chain
sequence of organisms in which one is eaten by the next member in the chain
food web
two or more interlinked food chains
pyramid of numbers
number of organisms at each trophic level in a food chain
nutrient recycling
way in which the elements are exchanged between the living and non living componenets of an ecosystem
pollution
any harmful addition to the environment
conservation
wise management of the existing natural resources in order to maintain a wide range of habitats and prevent the death/extinction of organisms
Intra specific competition
between members of the same species
Inter specific competition
members of different species
Competition
active struggle for a resource that is in short supply
contest competition
active physical contest between two individual organisms
scramble competition
all competing individuals get some of the resource
predator
catches,kills and eats other organisms
symbiosis
two organisms of different species live in close association and at least 1 benefits
qualitative survey
absence/presence
quantitative survey
no. of organisms
adaptation
alteration that improves organisms chance of survival/reproduction
ultrastructure
detail of a structure as seen using an electron microscope
TEM
internal structure
SEM
surface view
Chromatin
chromosomes elongated and not dividing
Using a light microscope
low power objective lens stage+slide coarse adjustment adjust light e.g. angle of mirror gigh power objective lens fine adjustment knob
observing animal cell
cotton swab-cheek cell
methylene blue
cytoplasm-pale blue
nucleus-dark blue
observing plant cell
onion-epidermis
iodine-cytoplasm yellow,nucleus orange
tissue culture
growth of cells in/on a sterile nutrient medium outside an organism
applications of tissue culture
skin grafts
micropropagation
solar energy
sun
cellular energy
energy stored in bonds of biomolecules
substrate
substance with which an enzyme reacts
product
substance an enzyme forms
bioprocessing
use of enzyme controlled reactions to produce a product
bioreactor
vessel in wich living cells/their products are used to make a product
immobilised enzymes
attached,or fixed to each other or an inert material
advantages of immobilised enzymes
reused
increased stability
cheaper
example of immobilised enzyme
lactase,lactose,glucose+galactose
effect of ph on rate of enzyme
ph buffer 4,one drop washing up liquid,blended celery,water bath at 25
volume of foam after 2 mins
repeat-buffer 7,10,13
effect of temp on enzyme
buffer 9,washing up liquid,blended celery,ice cold water
repeat at 10,20,30,40,50 and 60
Prepare an enzyme immobilisation
yeast-sucrase sodium alginate +water 5 mins yeast+water 5 mins calcium chloride syringe high-prevents clumping leave for 15 minutes
examining application of immobilised enzymes
seperating funnel
yeast+water-2nd seperating funnel
sucrose and water-half in each funnel
glucose test strips
active site
part of enzyme that combines with substrate
Induced fit model
substrate combines with active site active site changes shape slightly enzyme substrate complex substrate-product active site returns to original shape
enzyme specificity
each enzyme will react onlywith one particular substrate
optimum Ph
ph value at which enzyme works best at
denatured enzyme
lost its shape and can no longer function
