Cell Function And Homeostasis Flashcards
Labelled structures of the animal cell
Cellular structure
- Nucleus: Largest organelle, all cells (except Red Blood Cells): contains genetic material
- Plasma Membrane: Controls the passage of substances in and out of the cell regulating intracellular
environment
- Ribosome: Synthesise protein from amino acids using RNA template
-Mitochondria: Aerobic respiration with O2 & ATP- batteries of the body (these make all of our energy)
- Endoplasmic Reticulum:
-Smooth synthesis lipids and steroids hormones.
-Rough studded with ribosomes synthesis protein and leave by exocytosis
- Golgi apparatus: Synthesised proteins are packaged and stored here
- Lysosome: Small membranous vesicles containing enzymes
- Chromatin: helps compact DNA from longer strands into smaller packages as part of mitosis
- Centrioles: are responsible for producing cellular spindles in mitosis as well as making microtubules
Types of transport and examples of them.
Osmosis: movement of water down the concentration gradient -
Diffusion: movement of molecules from an area of high concentration to an area of low concentration
-
Active transport: transport of substances up the concentration gradient requiring
energy and carriers.
-
Eg Na/K pump K levels higher in the cell and NA outside. Particles are transported through pinocytosis, phagocytosis
How many different cell types are there and, examples of their scientific names?
Approx 200 different cell types:
These include:
Stem cells.
Red blood cells (erythrocytes)
White blood cells (leukocytes)
Platelets.
Nerve cells (neurons)
Neuroglial cells.
Muscle cells (myocytes)
Cartilage cells (chondrocytes)
What do cells do?
– Reproduce
– Nourishment (create and maintain)
– Movement (energy and transport)
– Excretion (get rid of waste)
– Growth
– Respiration
What are the 4 tissue types?
Connective tissue: Most abundant type of cells – binding, supporting, protecting (e.g. cartilage, blood, adipose, bone)
Epithelial tissue: Cells forming continuous sheets often lining body cavities (e.g. skin, gut lining, glands)
Muscle tissue
Skeletal muscle under voluntary control, attached to bone for motion/posture.
2) Smooth muscle forming walls of tubes e.g. airways, blood vessels, gut, bladder, uterus for propulsion of substances.
3) Cardiac muscle under involuntary control causing the heart to pump.
Nervous tissue: Neurones (nerve cells) conduct electrical impulses throughout the body (e.g. brain, spinal cord) to control body function/movement/secretion/senses.
Specialised cell vs tissue vs organ vs organ system vs organism
Groups of similar cells form TISSUES.
- Groups of TISSUES form ORGANS.
- 6 levels of organization
Organ -
grouping of 2 or more tissue types into recognizable structure with a specific function.
System -
collection of related organs with a common function. Organismal one living individual.
Inferior vs superior
Inferior means lower
Superior means higher
When to use hand sanitiser vs water and soap
When there is no visible dirt vs
If hands looks dirty
Someone is sick or diarrhoea
Sterile procedures
Dealing with bodily fluids
Before and after seeing patients
Before and after procedure
When touching anything in patient area or property
When to wear gloves?
When doing anything sterile
Taking blood
When using cleaning products
When hands are cracking, open wounds ect on you or the patient
Who do you speak to if your hands start to get irritated?
Occupational health and Lucy when at university.
Keep hands moisturised.
What is the Ordit process?
Someone within the hospital staff manager ect will stand near the doors of departments where hand sanitiser is and check and make a data spread on how many people (all staff) clean their hands between departments.
Rules for placement?
Report to uni if anything goes on
Bring little note pad, at least 2 pens, lunch box, water bottle, bob watch, wipeable shoes
Remove jumpers in people’s houses, community and clinical
Have uniform covered in public
Posterior vs anterior
Backwards vs forwards
Programmed cell death.
Apoptosis
Why does gut epithelium turnover every 3 days?
Due to HCL is stomach so it doesn’t burn through
Why does skin epidermis turnover every 2-4 weeks?
Due to exposure to sun, chemicals, cuts, burns etc
Homeostasis?
Is the balance when conditions in the internal environment are maintained within physiological limits.
How does homeostasis work?
- Receptors - capable of detecting changes to the body.
- By having a control system – to initiate corrective measures. Usually is
a “nerve” centre. - Effectors - to carry out corrective measures
The order of response in disruption of homeostasis?
Change in Stimuli -> Receptor (detects change) -> Control centre (e.g Pituitary gland) -> Effective -> Corrective response (e.g heat loss)
Negative feedback vs positive feedback
- If response reverses original stimulus = negative feedback (tends to
restore to normal levels) - If response enhances original stimulus = positive feedback (continues
to reinforce the original stimulus)
When formula milk has a 1 on it, what does it mean?
It means it can be given babies for 1st year of their life.
Why are extra products in baby formula maybe not good?
If it was proven to be healthy or beneficial, all formulas would have it in. -
These added extras may even increase the metabolic load for babies.
Breast feeding vs chest feeding
Same thing
Infant formula vs cows milk
Same thing
Why breast feeding matters?
For the baby: Breastfeeding is a natural form of protection against a range of illnesses, including infection, diabetes, obesity, heart disease, and sudden infant death syndrome (SIDS). Antibodies from mum even illness /disease mum hasn’t been exposed to.
For the mother: Breastfeeding is a natural form of protection against breast and ovarian cancer, heart disease, and osteoporosis. Exclusive breastfeeding temporarily reduces fertility, to enable birth spacing.
Mum can replenish natural body supply
What’s so special about human milk?
Human milk is matched to the needs of the baby The constituents of human milk change dependent upon when the baby is born, its age, and the environment that it lives in.
Human milk has live constituents As it hasn’t been pasteurised, it has live microbes, which are essential in colonising the baby with healthy bacteria. Human milk protects the baby’s gut Newborn babies have a ‘leaky’ gut, which harmful bacteria can latch on to. Human milk coats the gut wall to prevent harmful bacteria from colonising.
Immunoglobulins in breast milk?
IgM: IgM present in breastmilk increases responsiveness to the vaccination compared to formula fed babies. (Saso and Kampmann 2017) IgA: the first line of defence against pathogens that invade humans from mucosa. Coats the gut wall and protects the mucosal surfaces against entry of pathogenic bacteria and enteroviruses. It affords protection against: Escherichiacoli ( E.coli ), salmonellae , shigellae , streptococci , staphylococci , pneumococci , poliovirus and the rotaviruses .
IgD: combats disease without causing inflammation.
IgG: transfers across the placenta and through breastmilk, therefore passive immunity will be maintained while the baby is being breastfed by its mother.
IgE: small quantities in breastmilk for a longer period than in cow’s milk; implications unknown.
What does Baby Friendly Initiative do?
BFI have developed standards for universities, maternity units, neonatal units, health visitors, and children’s centres to improve the support that families receive in infant feeding.
What is blood pressure?
Force exerted by the blood on the blood vessel walls
(Blood pressure is highest in the arteries that are closest to heart)
How do you write blood pressure?
Systolic pressure – the pressure produced during
ventricular contraction. This is the maximum
pressure because it is when the arteries contain
the most blood. Diastolic pressure – the pressure produced when
the ventricular relaxes. When the arteries contain
the least amount of blood.
Systolic: top number Diastolic: bottom number
E.g 120/70
What is normal blood pressure?
100 - 140 bpm on top number
60-90 bpm on bottom for adult
Smaller people may have a lil lower BP
Both numbers would have to be in range to be healthy
What affects blood pressure?
Bad diet (salt), diabetes, someone who is wearing uniform scares them (white coat hypertension), Salt adsorbs water swelling up blood vessels
What is your peripheral temperature?
Peripheral temperature – often lower than core temperature and assists
with heat loss and gain. It is the temperature generated by skin.
E.g fingers
Babies body temp vs babies body temp?
Half a degree hotter than mum
What is pyrexia?
Pyrexia is an abnormally high temperature (38 ºC +), where the hypothalamus
‘thermostat’ has been reset higher. This can occur with infections.
A pyrexia = she hasn’t got pyrexia
36.5 - 37.5 c for babies
Paracetamol is amazing at lowering the temp of body
How do you take body temp?
Oral site (under tongue)
A branch of the carotid artery
(the sublingual artery) runs beneath the sublingual pocket. The blood within this vessel is travelling to the hypothalamus.
• The temperature can be
affected by environment factors such as cold or hot drinks, tachypnoea.
• When would you not use this
site?
Tympanic (ear)
Tympanic membrane shares
the same blood supply as the hypothalamus
• What can affect the
accuracy?
• Use disposable covers
• Insert probe into auditory
canal by pulling the pinna up
and back, thus straightening
the auditory canal and
exposing the tympanic
membrane
Factors influencing body temp?
Temperature is higher during ovulation
Fever
Digestion
Hot baths
Body temperature is lowest during the night
Procedure for taking body temp?
1.Gain informed consent
2.Wash hands
3.Take the equipment and disposable cover to the woman
4.Ensure you have evaluated the chose site and equipment
5.Apply disposable cover
6.Take the temperature (how is dependent on equipment used)
7.Dispose of cover
8.Explain findings
9.Wash hands
10.Document and act accordingly
Normal pulse vs pregnant women’s pulse in labour?
60-80 bpm
60-100 bpm
Pulse points?
Radial (wrist)
Brachial (upper side of arm)
Carotid (neck)
How to check breathing rate?
Pretend your taking their pulse and watch their chest rise an fall. Maybe even lay their arm across their chest.
How to check oxygen saturation?
The finger thingy machine
Symptoms of blood loss?
Tiredness, weakness, paleness of skin, limited speech, high heart rate, dizziness
low blood pressure (less blood in body), confusion,
Can lead to heart attack / stroke due to lack of oxygen
How are red blood cells created?
Starts in the bone marrow as a pluripotent stem cell - Differentiates into pro erythroblast
- Synthesis of haemoglobin and nucleus expelled = reticulocyte
-Reticulocyte matures over 1-2 days after leaving bone marrow =
erythrocyte. -
Erythropoiesis stimulated by low O2 levels (so more RBC is made e.g athletes train at high altitudes to promote increase RBC)
Rhesus incompatibility in pregnancy.
Mother is Rh Neg and fetus is Rh Pos.
RhD antigens from foetus mix with maternal blood.
Mother makes anti D antibodies.
IgG antibodies due to their molecular size can then cross the placenta. -
These anti D antibodies will then attack and haemolyse the foetal erythrocytes carrying the D surface antigen.
-
This can cause iso-immunisation, fetal anaemia and hydrops fetalis (severe liver swelling and fluid build up in the foetus or newborn), possibly fatal)
-
May lead to jaundice (makes skin yellow) in the first 48 hours of life…
What is the Gi tract?
Gastro-intestinal system is a tube + supporting organs: salivary glands, liver (gallbladder) & pancreas
The organs that food and liquids travel through when they are swallowed, digested, absorbed, and leave the body as feces. These organs include the mouth, pharynx (throat), esophagus, stomach, small intestine, large intestine, rectum, and anus.
What does the gut do?
The gut is an external surface (like skin)…..let me explain
The purpose of the gut is to:
Take a burger/carrot
Break it down (physically/chemically)
Until it is small enough to…
Be absorbed through the gut wall into blood/lymph
Energy/nutrients can then be utilised
Get rid of what we don’t need
Plus:
Absorb water
Excrete cholesterol
Synthesise some vitamins
How is the tube (oesophagus) in the Gi tract divided?
Sphincters that have diff functions?
A ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body.
Goblet cells and mucus?
Keeps tract lubricated so food passes easily
Also prevents us from digesting / breaking dawn our own bodies
Lines our tract so digestive enzymes don’t eat into our organs
Peristalsis vs segmentation
Moves food forward (happens in oesophagus and it squeezes in turn so food moves forward)
Back and forth mixes (doesn’t squeeze in order so food moves back and forth)
Keywords:
• mastication
• deglutition
• chewing
• swallowing
Liver vs gallbladder vs bile
Bile is created in Liver
Bile is stored in gallbladder
Bile needed to break down down fat when detected in small intestine. Contains Bile salts
These help emulsify fats into smaller droplets
Makes it possible to absorb cholesterol and fatty acids and fat-soluble vitamins
What is the rugae of the stomach?
The folds that then allow the stomach to stretch
Carbohydrates
Protein
Fat
Carbohydrate to sugars
Long chains of sugars (starch) in rice, potatoes etc or shorter chains of sugars like lactose in milk
Broken down by enzymes
Into single sugar units (monosaccharides) to be absorbed
Only monosaccharides can be absorbed
Starts in the mouth and oesophagus via salivary amylase Continues in the enterocytes in the small intestine via lactase, maltase, and sucrase
Protein to amino acids
Long chains of amino acids (polypeptides)
Broken down by protease enzymes like pepsin
Problem with digesting ingested proteins is that the gut is also made of proteins
How do we stop the enzymes digesting the gut?
Proteases are stored as inactive form and activated only when in a safe environment e.g. activated by
the gastric juice in the stomach: pepsinogen ,pepsin
Fat globules are emulsified by bile salts in bile. They can then be broken down further by lipases (enzymes) into fatty acids (monoglycerides). The bile salts and the fatty acids form ‘micelles’ which can be absorbed by the villi of the small
intestine.
Extra-uterine meaning
Outside womb
Acrocyanotic meaning
The middle of body is well coloured but hands and feet are pale.
Benefits of skin to skin contact?
Stimulates release of prolactin (hormone for the production of milk) and oxytocin (love hormone).
Calms and relaxes baby and mother
Regulates baby’s heart rate and breathing
Regulates baby’s temperature
Stimulates breast-seeking behaviour and interest in
Stimulates endorphin (Pain/ stress hormone) release
-microbiome feeding
- Protects baby from infection – colonises their
What is the physiology of skin to skin contact?
Skin to skin contact in the first hour encourages: (Boobs act like thermostat for baby to regulate babies body temp)
An early first feed (Lau et al, 2017), and higher blood glucose levels (Moore et al 2016) counteract physiological drop in
blood glucose after birth.
The baby to familiarise itself with its mother’s chest, and learn how to locate and self-attach to the breast.
- Reduction in mean time for placental expulsion. (Marin Gabriel
et al 2009)
- Thermal regulation (Marin Gabriel et al 2009) avoiding hypothermia.
Normal transition to extra utero life more stable heart
rate, respiratory rate and oxygen saturation. (Moore et al 2016) -
Hypoxia
Low oxygen
9 stages of neonatal behaviour
1.Birth Cry
2.Relaxation
3.Awakening
4.Activity
5.Rest
6. Crawling
7. Familiarisation
8. Suckling
9. Sleep
These behaviours only occur in the habitat of the maternal chest – if the baby is removed from this habitat, it must start these steps again from the beginning, when next put in skin to skin contact.
Positive feedback loop in terms of labour?
Positive feedback loop: mothers are rewarded with this feel-good hormone when they ‘mother’ their baby.
How do we create an environment which is conducive to oxytocin release?
Same environment for making a baby so dark, quiet and private
Actions of prolactin when progesterone is absent/low.
Prolactin is no longer suppressed by the progesterone being excreted by the placenta, so prolactin receptors are activated. High circulating levels of prolactin can now lock into the receptor sites to stimulate milk production. Ongoing prolactin production is stimulated by the baby suckling at the breast. When the baby suckles, prolactin is released from the anterior pituitary gland.
Positive feedback loop: the more the baby feeds, the more prolactin is released, the more milk is made.
Colostrum
Colostrum is a concentrated version of breastmilk
Packed with protective factors
Concentrated nutrition
Small volumes – intentionally
Laxative effect – to clear meconium
Slide adapted from UNICEF UK
How does breast milk help cure the baby of a pathogen the mother has never been exposed to?
Backwards spittle then the mother’s body produces antibodies and then the baby gets them through the breast milk.
What are the first signs of pregnancy?
~Missed period
~Random & morning sickness
~Cravings
~Blue vein across your chest cause veins dilated due to increase vascularity
~Sore tender breast
~Increased senses
~Hormone changes (more progesterone) - mood change and skin issues
~Change in colour of titties
~Opposite of food craving
~Vaginal bleeding
~Breast size
~Fatigue
~A bump
~ A test
Diagnosis of pregancy
• Palmer’s sign: from 4-8 weeks, regular contractions can be elicited during bimanual examination.
• Hegar’s sign: present in two thirds of cases, and present from around 6 weeks. Fingers oppose below the body of the uterus on bimanual examination due to a softening in the consistency of the uterine isthmus.
• Goodall’s sign: from 6 weeks, the cervix softens.
• Copious mucoid discharge: present from around 6 weeks. (Milky and no smell)
• Jacquemier’s sign: present from around 8 weeks, increased blood supply to the anterior vaginal wall gives it a bluish colouration.
• Osiander’s sign: present at 8 weeks, increased pulsation felt through lateral fornices.
• Quickening: first fetal movements felt between 16-18 weeks.
Pregnancy tests
• Pregnancy tests depend on the detection of the hormone hCG.
• hCG: human chorionic gonadotrophin. It is produced by the cells that
surround the growing embryo. The presence of hCG almost always
indicates pregnancy.
• hCG can be detected in maternal blood or urine.
• Collection of urine: first void in the morning in a clean container.
• Reliability: dependent upon storage of the test, usage, timing.
(Can be a sign of cancer if the test comes out positive for a man)
How to calculate EDD or EDB?
- Work from first day of last menstrual period
- Add 9 calendar months and 7 days (40 weeks)
HOWEVER: Based on a 28 day, regular menstrual cycle (add or subtract from 28 days, e.g. 27 day cycle minus 9)
Neagle’s rule: 280 day pregnancy (40 weeks) Consider: unplanned pregnancies (Hunter 2009), ovulation tracking, IVF transfer.
What does LMP stand for?
Last Menstrual Period
What information will be taken down at the booking appointment?
Medical history
Medical -
Underlying disease; diabetes, cardiovascular disease, hypertension
-
Trauma e.g. fractured pelvis - -
Previous or current infections -
Female Genital Mutilation
Mental health illness
Surgical -
Anaesthetic history
-
Type of surgery -
Blood Transfusion
Including: family history, hospital admissions and medications
Obstetric history
Previous experiences are indicators of possible further complex needs. For
example:
Previous caesarean sections – emergency or elective - - - - -
-
Terminations and miscarriages
Instrumental births
3rd/4th degree perineal tears
Breech birth
Intra-uterine growth restricted baby/macrosomic
Lifestyle
- Smoking, drugs, alcohol (Have specialist service to help stop if they really struggle ), lack of exercise (Avoid things that increase risk of falling, stress on abdomen ect) (Exercise helps for easier and shorter labour), diet, medication (e.g Vitamin D/ folic acid that are recommended whole pregnancy)
What is antenatal screening?
Screening tests help to identify people at a higher chance of having or developing a health condition
Screening tests are optional
Some screening tests give a ‘chance’ result, rather than a definite diagnosis
Screening tests are not perfect: they may give a ‘false positive’ or ‘false negatives’
They may use many different types of test technology, such as blood tests,
ultrasound tests, and physical examination.
External genitalia name vs internal genitalia
Vulva
The vagina, the uterus, two uterine tubes and 2 ovaries
Vagina has rugae.
Yes or no?
Yes
Anatomical relations to the vagina.
Anterior: Bladder
Posterior: Rectum
Superior: Uterus
Inferior: External genitalia
Layers of the vagina
Lining: squamous epithelium, arranged in rugae.
Kept moist by cervical secretions pH 4.9-3.5-acidic due to presence of Doderlein’s bacilli.
Muscle layer: weaker inner circular fibres and stronger outer longitudinal fibres
Pelvic fascia: connective tissue surrounding the vagina
How long is the none pregnant uterus?
The non-pregnant uterus is 7.5 cm long, 5 cm wide and 2.5 cm in depth, each wall being 1.25 cm thick, and weighs ~60 grams.
The cervix
The cervix is part of the uterus.
The lower part sits within the vagina, and upper part sits above the vagina.
The cervical canal is made up of columnar epithelium that secretes mucus (known as compound racemose glands)
The muscle fibres are embedded in collagen enabling it to stretch in labour.
On a normal day your cervix feels sturdy like the texture of the nose
Cervix softens before labour
Hormonal trigger
Hypothalamus releases luteinising hormone releasing hormone [LHRH] LHRH acts on the anterior pituitary gland, causing it to release follicle stimulating hormone [FSH] and luteinising hormone [LH] FSH and LH cause the ovaries to secrete ostrogens.
Oestrogens are responsible for secondary sex characteristics.
During the reproductive cycle
During each cycle, one (or so) follicles mature. Maturation is controlled by the hypothalamus secretes luteinising hormone releasing hormone [LHRH] and the anterior pituitary gland, which releases gonadotrophins (follicle stimulating hormone [FSH], and luteinising hormone [LH]), both of which act on the ovary.
What are secondary sex characteristics in females?
• Maturation of the uterus, uterine tubes and ovaries.
• Development and enlargement of the breasts.
• Growth of pubic and axillary hair.
• Increase in height.
• Widening of the pelvis.
• Increased fat deposition in the subcutaneous tissue, especially at the hips and breasts.
Reproductive cycle key words.
Menarche: onset of menstruation
Menopause: ceasing of menstruation
Menstruation: a ‘period’ of vaginal bleeding as the lining of the uterus sheds and is passed through the vagina.
Reproductive cycle: Also known as the menstrual cycle.
A series of events, occurring regularly in females every 26-30 days throughout the childbearing period between menarche and menopause.
The cycle consists of a series of changes taking place concurrently in the ovaries and uterine lining, stimulated by changes in hormones.
The reproductive cycle in the uterus.
Menstrual: Days 1-4
Progesterone and ostrogen levels therefore fall, and the functional layer of the endometrium is shed in menstruation as the myometrium contracts.
Proliferative: Days 5-14
The maturing ovarian follicle stimulates the thickening (regrowth) of the functional layer of the endometrium in preparation for the reception for the fertilised ovum. The endometrium thickens, becoming very vascular and rich in mucus-secreting glands.
This stage ends at ovulation.
Secretory: Days 15-28
Progesterone from the corpus luteum stimulates the endometrium to become oedematous and the secretory glands produce increased amounts of watery mucus. This assists the motile spermatozoa through the uterus to the uterine tubes, where the ovum is usually fertilised. This stage begins at ovulation.
NAD meaning
No abnormalities discovered
MLU meaning
Midwifery led unit is a dedicated unit for women with low risk pregnancy.
