Anatomy Flashcards
What is a Anatomy and physiology
Branches of anatomy
What is the hierarchy of structural organization
Name three tissues that make up the blood vessels
Anatomy – the study of the structure of the human body
• Physiology – the study of body function
Branches of anatomy
• Gross anatomy
• Microscopic anatomy (histology) • Surface anatomy
• Anatomical terminology
• Based on ancient Greek or Latin
• Provides standard nomenclature worldwide
Chemical Level – atoms form molecules
• Over 90% of body = 4 atoms
• Carbon, Nitrogen, Oxygen, Hydrogen
• Cellular level – cells and their functional subunits • 50 – 100 trillion
• Red blood cell, neuron, etc.
• Tissue level – a group of cells performing a common function
• epithelial, connective, muscle, nervous
The Hierarchy of Structural Organization • Organ level • discrete structure • more than one tissue • liver, brain, heart, etc. • Organ system • organs working together • digestive- esophagus, stomach, intestine • Organismal level– the result of all simpler levels working in unison
Connective tissues
Epithelial tissue
Smooth muscle tissue
What is the anatomical position?
What is the directional position?
Anatomical position—a common visual reference point
• Person stands erect with feet together and eyes forward
• Palms face anteriorly with the thumbs pointed away from the body
Directional terminology— refers to the body in anatomical position
• Standardized terms of directions are paired terms
What is superior(cranial),inferior(caudal),anterior(ventral),posterior(dorsal),medial,lateral,proximal,distal,superficial (external),deep(internal),Ipsilateral,contralateral
Toward the head end or upper part of a structure or the body ;above
Away from the head end or toward the lower part of a structure or the body ;below
Anterior:toward or at the front of the body ;in front of
The breastbone is anterior to the spine
Posterior: toward or at the back of the body;behind
The heart is posterior to the breastbone
Medial:toward or at the midline of the body ;on the inner side of
Lateral: away from the midline ;on the outer side of the body
Proximal:closer to the origin of the body part or the point of attachment of a limb to the body trunk
Example is the elbow is proximal to the wrist
Distal: farther from the origin of the body part or the point of attachment of a limb to the body trunk
Example the knee is distal to the thigh
Toward or at the body surface
Away from the body surface or more internal example the lungs are deep to the skin
Ipsilateral: On the same side example the right hand and right foot are ipsilateral
Contralateral:On opposite sides
Cephalic means? Brachial means? Antebrachial means? Carpal means? Coxal means? Femoral means? Crural means? Hallux means? Pollex means?
What does the coronal plane ,transverse,oblique plane ,median planemean?
Head Arm Forearm Wrist Hip Thigh Leg Hallux:ANATOMY a person's big toe. ZOOLOGY the innermost digit of the hind foot of vertebrates. Pollex:the innermost digit of a forelimb, especially the thumb in primates.
Coronal (frontal) plane
• vertical
• divides body into anterior and posterior
Median (midsagittal) plane
• vertical in midline
• divides body into left and right
- Transverseplane
- Horizontal
- divides body into superior and inferior
An oblique plane is a plane that can literally be any type of angle other than a horizontal or vertical angle. It divides the plane at an angle
State the difference between mucous and serous membranes and give some examples
What are serous cavities and name the two layers
- Mucous membranes - line passages that communicate with the air
- open to outside
- e.g. respiratory and alimentary tracts
- have cells and associated glands that secrete mucus
- Serous membranes – line passages that are closed to outside
- Dorsal (cranial cavity which contains the brain and the vertebral cavity which contains the spinal cord ) and ventral cavities(thoracic cavity which contains the heart and lungs ,diaphragm is between the thoracic and abdominal cavity,abdominal cavity contains the digestive viscera,pelvic cavity contains the bladder, reproductive organs and rectum )
- Each containing internal organs
Serous cavities – space lined by a serous membrane
• 2 layers
• Parietal serosa – outer wall of the cavity
• Visceral serosa – covers visceral organs
Lungs: Outer balloon wall (comparable to parietal serosa) Air (comparable to serous cavity) Inner balloon wall (comparable to visceral serosa)
Heart:
Parietal pericardium
Pericardial cavity with serous fluid
Visceral pericardium
From outside to outside the lung : Ribs Parietal pleura Pleural cavity with serous fluid Visceral pleura Diaphragm
Name the organs in the nine regions of the abdomen
What are the three components of the cells
Name some organelles in the cytoplasm and their functions
Right hypo:liver and gallbladder
Epigastric region:oesophagus and stomach
Left hypo:stomach ,spleen,diaphragm
Right lumbar: Ascending colon of large intestine
Umbilical: Small intestine, Transverse colon of large intestine
Left lumbar:descending colon of large intestine
Right iliac:caecum and appendix
Hypochondriac :urinary bladder
Left iliac :initial part of the sigmoid
The stomach enters the small intestine through the duodenum (duodenum,jejunum,iluem as parts of the small intestine)
Large (colon,caecum,rectum)
Cells –smallest living units in our bodies
• 3 components
• Plasma membrane: Contents: lipid bilayer and proteins
Selectively permeable
• Diffusion – movement of particles from high to low concentration
• Osmosis – the diffusion of water across a membrane Goal of each = even out concentrations
Endocytosis(example is phagocytosis) and exocytosis
• Nucleus
• Cytoplasm/cytosol
Organelles – “little organs”
- Ribosomes
- Site of protein synthesis
- Endoplasmic reticulum
- Rough ER
- ribosomes stud external surfaces
- Smooth ER
- no ribosomes
- phospholipids synthesis
- various other functions
- Produces testosterone in the testes
- Detoxifies drugs in the liver
• Golgi apparatus
Sorts products of rough ER and sends them to proper destination
• Lysosomes
• contain digestive enzymes
- Mitochondria
- “powerhouse”
- aerobic respiration
- with oxygen
- The nucleus – control center of cell
- DNA
Centrioles are paired barrel-shaped organelles located in the cytoplasm of animal cells near the nuclear envelope. Centrioles play a role in organizing microtubules that serve as the cell’s skeletal system. They help determine the locations of the nucleus and other organelles within the cell.
During mitosis or cell division, the centrosome and centrioles replicate and migrate to opposite ends of the cell. Centrioles help to arrange the microtubules that move chromosomes during cell division to ensure each daughter cell receives the appropriate number of chromosomes.
What is embryology
How many weeks is the embryonic period and how many is the fetal period and state the major events that occur at both periods
Embryology – study of the origin and development of single individual
- Prenatalperiod
- Embryonic period – first 8 weeks
- Fetal period – remaining 30 weeks
Duration: First 8 weeks postfertilization
Major events: Organs form from three primary germ layers.
The basic body plan emerges.
Fertilization to 1 week conceptus to 3week embryo (3mm) to 5week embryo(10mm) to 8 week embryo (22mm)
Fetal period:
Duration is 9-38 weeks after conception or until birth
Major fetal events-organs grow in size and complexity
Embryonic period :
- Week 1 – from zygote to blastocyst
- Conception – in lateral third of uterine tube
- Zygote (fertilized oocyte) moves toward the uterus
- Blastomeres – daughter cells formed from zygote
- Morula – cluster of 12–16 blastomeres
- Blastocyst – fluid-filled structure – about 60 cells
- Cleavage - Cell division without growth
State the events that occur in the first six days of development
State the parts of the blastocyst and their functions
State the difference between a morula and a blastocyst
What nourishes the blastocyst?
Day one:zygote is formed Day 2:4 cell stage Day 3:Morula: A morula (Latin, morus: mulberry) is an early-stage embryo consisting of a solid ball of cells called blastomeres, contained within the zona pellucida. Gives rise to: Blastula, Blastocyst Precursor: Zygote
After fertilisation, the zygote starts dividing (cleavage) by mitosis. The daughter cells are called blastomeres. The embryo with 8-16 daughter cells is called the morula. It takes around 1-2 days for morula to become a blastocyst after dividing.
Day 4:early blastocyst-Three days after fertilization, a normally developing embryo will contain about six to 10 cells. By the fifth or sixth day, the fertilized egg is known as a blastocyst — a rapidly dividing ball of cells. The inner group of cells will become the embryo. The outer group will become the cells that nourish and protect it.
Day 6:implanting blastocyst
The blastocyst possesses an inner cell mass (ICM), or embryoblast, which subsequently forms the embryo, and an outer layer of cells, or trophoblast, which later forms the placenta and outer chorionic sac.The trophoblast surrounds the inner cell mass and a fluid-filled, blastocyst cavity known as the blastocoele or the blastocystic cavity.
A morula is distinct from a blastocyst in that a morula (3–4 days after fertilization) is a mass of 16 totipotent cells in a spherical shape whereas a blastocyst (4–5 days after fertilization) has a cavity inside the zona pellucida along with an inner cell mass.
Morula Cells (Mrl) The morula stage is usually defined as the stage in which the embryo consists of 16-32 cells.
A differentiating morula is a blastocyst
The trophoblastic cells digest endometrial cells, absorbing the nutrients and transferring them to the blastocyst to provide further sustenance
At week two of development of an embryo,what kind of embryo is formed ? And state the parts of the embryo formed at two weeks
At week three of development wheat kind of embryo is formed and state the parts of the embryo at that stage
The Two-Layered Embryo
• Bilaminar embryonic disc – inner cell mass divided into two sheets
Within the cytotrophoblast is the ball of ICM, and during the second week of human development, the ICM cells spread into a flattened tissue layer and differentiate into a two-layered tissue containing epiblast (columnar epithelial cells) and the hypoblast (cuboidal epithelial cells),
• Epiblast and the hypoblast
• Together make up the bilaminar embryonic disc
- Amniotic sac – formed by an extension of epiblast
- Outer membrane – forms the amnion
- Inner – forms the amniotic sac cavity
- Filled with amniotic fluid
- Yolk sac – formed by an extension of hypoblast
- Digestive tube forms from yolk sac
The hypoblast is the layer facing the blastocoel, while the epiblast is on the other side. Let’s imagine each of these layers as a flat balloon. The balloons expand to fill the space, and become the two new cavities: the primitive yolk sac on the side of the hypoblast and the amniotic cavity on the side of epiblast. The amniotic cavity will eventually surround the fetus
The Three-Layered Embryo
• Primitive streak – epiblast cells migrate inward. The beginning of gastrulation is marked by the appearance of a groove in the caudal end of the epiblast layer known as the primitive streak. [6] Thus, the formation of primitive steak firmly establishes the cranial/caudal axis. The primitive streak initially forms via a thickening of cells near the connecting stalk.
• A process called Gastrulation
• Endoderm – formed from first migrating cells • replaces hypoblast
• Mesoderm – the next group of migrating cells • between epiblast and endoderm
• Ectoderm – cells left at surface and don’t migrate inward
• formed from epiblast cells
During gastrulation the three germ layers form(ectoderm,mesoderm,endoderm),the cell mass is now known as a gastrula
Step 5a: The primitive streak forms
Step 6: The notochord is formed
What is zona pellucida?
How many cells does a zygote have?
Why can miscarriage occur?
How does implantation of a blastocyst ovcur?
A membrane surrounding the egg, called the zona pellucida, has two major functions in fertilization. First, the zona pellucida contains sperm receptors that are specific for human sperm. Second, once penetrated by the sperm, the membrane becomes impermeable to penetration by other sperm.
The egg is enveloped in an extracellular matrix called the zona pellucida. Sperm can fertilize the egg in the zona pellucida (ZP), which prevents the fertilized egg, called a zygote, from adhering to the wall of the fallopian tube.
The single-cell embryo is called a zygote.
Implantation is a process in which a developing embryo, moving as a blastocyst through a uterus, makes contact with the uterine wall and remains attached to it until birth. The lining of the uterus (endometrium) prepares for the developing blastocyst to attach to it via many internal changes. Without these changes implantation will not occur, and the embryo sloughs off during menstruation.
The window of endometrial receptivity is restricted to days 16-22 of a 28-day normal menstrual cycle, 5-10 days after the luteinizing hormone (LH) surge (Navot et al., 1991). The uterus then continues into the non- receptive period for the remaining cycle as the late luteal phase until menstruation ensues. The risk of spontaneous abortion significantly increases with implantation beyond this window (
So if the blastocyst implants beyond the window of the endometrium being conducive for the growth of the blastocyst then there’s an increased risk of miscarriage cuz the endometrium can’t support the blastocyst properly since the window of the endometrium being ready for the blastocyst has passed
The early embryo enters the uterine cavity as a morula and becomes a 32 to 256-cell blastocyst before implantation. Implantation begins with the loss of the zona pellucida known as hatching about 1-3 days after the morula enters the uterine cavity in preparation for attachment. The active blastocyst undergoes structure changes such that a more irregular surface with more microvilli is observed with accumulation of glycogen granules in the cytoplasm (Naeslund et al., 1980). In conclusion, the window for successful implantation could be defined as a limited time span when the activated stage of the blastocyst is superimposed on the receptive state of the uterus
Implantation consists of three stages: (a) the blastocyst contacts the implantation site of the endometrium (apposition): Implantation begins with apposition of the blastocyst at the uterine epithelium, generally about 2-4 days after the morula enters the uterine cavity. The implantation site in the human uterus is usually in the upper and posterior wall in the midsagittal plane. During apposition process, the blastocyst differentiates into an inner cell mass (embryo) and trophectoderm (placenta). Stromal cells surrounding the implanting blastocyst differentiate into a specialized cell type called decidual cells, via a process known as decidualization
b) trophoblast cells of the blastocyst attach to the receptive endometrial epithelium (adhesion); Invasion The process of implantation allows fetal trophoblast cells to invade and migrate into the maternal decidua. By this time, the trophoblasts at the implantation site have formed masses of cytotrophoblasts and syncytiotrophoblasts. Eventually, trophoblast cells destroy the wall of the maternal spiral arteries, converting them from muscular vessels into flaccid sinusoidal sacs lined with endovascular trophoblast (Burrows et al., 1996). The aim of invasion is to reconstruct the maternal spiral arteries, which will maintain a high blood flow between the fetus and the mother, replacing small, high-resistance vessels with large, low-resistance vessels. The extent of trophoblastic invasion determines later placental efficiency and fetal viability in late gestation. Deficiencies in trophoblastic invasion give rise to adverse pregnancy outcomes such as intrauterine growth
and (c) invasive trophoblast cells cross the endometrial epithelial basement membrane and invade the endometrial stroma (invasion)
What are the four stages of embryonic development
What do the three layers formed in gastrulation go on to form in the baby
This cut is the primitive streak, and it cuts from the caudal (anus) end in toward the end that will eventually become the head (the rostral end). This streak determines the midline of the body, and separates the left and right sides. True or false
Directly beneath the primitive streak the mesoderm (the middle germ layer) forms a thin rod of cells known as the notochord. The notochord helps define the major axis of our bodies, true or false
The four stages of embryonic development are morula, blastula, gastrula and organogenesis.
Ectoderm Outer, external Epidermis (outer layer of skin), hair, nails, brain, spinal cord, peripheral nervous system
Mesoderm Middle Muscle, bone, connective tissue, notochord, kidney, gonads, circulatory system
Endoderm Within Epithelial lining of the digestive tract; Stomach, colon, liver, pancreas, bladder, lung
What is neurulation and when is it formed and what parts are formed during this process
Name the layers of the mesoderm and the organs they form
Neurulation – ectoderm starts forming brain and spinal cord
• Neural plate – ectoderm thickens
• Neural groove – ectoderm folds inward
• Neural tube – a hollow tube forms
• Cranial part of the neural tube becomes the brain. Neural tube forms the brain and spinal cord
• Neural crest – forms sensory nerve cells, ganglia, and melanocytes
Neurulation is done after the notochord is formed
Tubes form, making a neurula
Step 6a: The notochord induces the formation of the neural plate
Step 6b: The neural plate folds in on itself to make the neural tube and neural crest
Step 7: The mesoderm has five distinct categories
Meanwhile, the mesoderm can be subdivided into the axial, paraxial, intermediate, and lateral plate mesoderms. The notochord came from the axial mesoderm. The paraxial mesoderm will give rise to somites, which will differentiate into muscle, cartilage, bone, and dermis. Somite derivatives create a segmented body plan (see right). The intermediate mesoderm is the origin of our urogenital system – our kidneys, gonads, adrenal glands, and the ducts that connect them. The lateral plate mesoderm will give rise to the heart (the first organ to develop!), blood vessels, the body wall, and the muscle in our organs.
Also at the same time, the endoderm is rolling into a tube as well – the digestive tract. The digestive tract is subdivided into the foregut, midgut, and hindgut. Each subdivision has its own nerve and blood supply. Organs related to the GI tract actually start off as outpouchings of this tube. The foregut gives rise to the esophagus, stomach, part of the duodenum, and the respiratory bud, which will eventually develop into the lungs. The second half of the duodenum through to the transverse colon arise from the midgut. The remainder of the GI tract, including the rest of the transverse colon, the descending colon, the sigmoid colon, and the rectum are formed from the hindgut.
The The Mesoderm Begins to Differentiate after neurulation
• Somites – our first body segments • Vertebrae, ribs, and axial muscles • Paraxial mesoderm
• Intermediate mesoderm – begins as a continuous strip of tissue just lateral to the paraxial mesoderm
• Urogenital system
True or false
What happens at week four
By the end of the second month, all organs have appeared and the placenta is fully functioning.
• Embryonic development complete true or false
Fetal Development
• At the beginning of the third month, head growth begins to slow and the body increases in length.
• Ossification centers appear in bones.
• Sex can be determined sometime in the third month. True or false
Fifth through Seventh Months
• Mother begins to feel fetal movement. • Lungs lack surfactant.
True or false
Eighth and Ninth Months
• Fetus usually rotates so head is pointed down toward cervix.
True or false
State the fetal development of the baby at 8 weeks,9-12weeks,13-16,17-20,21-30,30-38
The body takes shape at week four.
8 weeks-eyes and ears first look human;neck region firs becomes evident
All major divisions of the brain are present
First brain waves occur in the brain stem
Liver is disproportionately large
Bone formation has just begun ,weak muscle contractions occur
Limbs are complete ,digits are initially webbed but fingers and toes are free by the end of the 8th week
The cardiovascular system is fully functional,the heart has been pumping blood since week 4
Approximate crown to rump length is 3cm(1.2inches),weight is 2g(0.06 ounces)
9-12weeks:body is elongating,brain continues to enlarge,retina of the eye is present
Skin epidermis and dermis are differentiated
Right and left halves of the palate(roof of the mouth) are fusing
Walls of hollow visceral organs are gaining smooth muscle ,intestines move into the body cavity.
Blood cell formation begins in the bones marrow (also occurs in the liver and spleen)
Notochord is degenerating and bone formation is accelerating
Sex can be determined from the genitals
Approximate crown to rump length at end of 12 weeks:6cm
13-16:sucking motion of lips occur, eyes flinch if stimulated
Body outgrows head
Limbs are not disproportionately small anymore
Hard palate is fused
Kidneys attain their typical structure
Most bones are now distinct and joint cavities are apparent
Approximate crown to rump length at end of 16weeks:11cm
17-20weeks:eyelashes and eyebrows are present,fatty skin secretion covers the body
Silk like hair called lanugo covers the skin
Quickening occurs or mother feels foetus moving
Body first bends into fetal position due to limited space in the uterus
Limbs achieve near final proportions
Rapid brain growth,hearing is functional
Approximate crown to rump length at end of 20weeks:16cm
21-30weeks:eyes open,body weight and size substantially increase
Fingernails and toenails are complete
Skin is wrinkled and red
Fatty layer under the skin the (hypodermis )is just starting to gain fat so the body is lean
Bone marrow becomes the only site of blood cell formation
Cerebrum grows
Convolutions develop on brain surface
Testes reach the scrotum in month 7 for males
Lungs develop
Approximate crown to rump length at end of 30weeks:38cm
Anatomy is the Study of the structure of the body and the physical relationship between body systems
It comes from a Greek word ‘anatome’ meaning “to cut open”, ‘cutting up’ or ‘take apart’. First used by Aristotle (384-322 BC)
A Latin word ‘dissecare’ has similar meaning.
True or false
What are the different ways anatomy can be approached
What are the main areas of anatomy
Anatomy can be approached in different ways:
Regional/Topographic Anatomy: studies regions of the human body. E.g. abdomen, leg, head and neck, Upper limb & thorax.
Systemic Anatomy: the body structure is studied by systems. E.g. cardiovascular system Reproductive system etc.
Clinical (applied)-Endoscopy & Imaging tech
Surface Anatomy: the study of internal organs as they relate to the overlying skin surface.
MAIN AREAS OF ANATOMY
GROSS ANATOMY-Macroscopic
HISTOLOGY-Microscopic
EMBRYOLOGY-Developmental
